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How to use property in dynamic class if i know the name of it [duplicate]

I am trying implement the Data transformation using Reflection1 example in my code.
The GetSourceValue function has a switch comparing various types, but I want to remove these types and properties and have GetSourceValue get the value of the property using only a single string as the parameter. I want to pass a class and property in the string and resolve the value of the property.
Is this possible?
1 Web Archive version of original blog post

public static object GetPropValue(object src, string propName)
{
return src.GetType().GetProperty(propName).GetValue(src, null);
}
Of course, you will want to add validation and whatnot, but that is the gist of it.

How about something like this:
public static Object GetPropValue(this Object obj, String name) {
foreach (String part in name.Split('.')) {
if (obj == null) { return null; }
Type type = obj.GetType();
PropertyInfo info = type.GetProperty(part);
if (info == null) { return null; }
obj = info.GetValue(obj, null);
}
return obj;
}
public static T GetPropValue<T>(this Object obj, String name) {
Object retval = GetPropValue(obj, name);
if (retval == null) { return default(T); }
// throws InvalidCastException if types are incompatible
return (T) retval;
}
This will allow you to descend into properties using a single string, like this:
DateTime now = DateTime.Now;
int min = GetPropValue<int>(now, "TimeOfDay.Minutes");
int hrs = now.GetPropValue<int>("TimeOfDay.Hours");
You can either use these methods as static methods or extensions.

Add to any Class:
public class Foo
{
public object this[string propertyName]
{
get { return this.GetType().GetProperty(propertyName).GetValue(this, null); }
set { this.GetType().GetProperty(propertyName).SetValue(this, value, null); }
}
public string Bar { get; set; }
}
Then, you can use as:
Foo f = new Foo();
// Set
f["Bar"] = "asdf";
// Get
string s = (string)f["Bar"];

What about using the CallByName of the Microsoft.VisualBasic namespace (Microsoft.VisualBasic.dll)? It uses reflection to get properties, fields, and methods of normal objects, COM objects, and even dynamic objects.
using Microsoft.VisualBasic;
using Microsoft.VisualBasic.CompilerServices;
and then
Versioned.CallByName(this, "method/function/prop name", CallType.Get).ToString();

Great answer by jheddings. I would like to improve it by allowing referencing of aggregated arrays or collections of objects, so that propertyName could be property1.property2[X].property3:
public static object GetPropertyValue(object srcobj, string propertyName)
{
if (srcobj == null)
return null;
object obj = srcobj;
// Split property name to parts (propertyName could be hierarchical, like obj.subobj.subobj.property
string[] propertyNameParts = propertyName.Split('.');
foreach (string propertyNamePart in propertyNameParts)
{
if (obj == null) return null;
// propertyNamePart could contain reference to specific
// element (by index) inside a collection
if (!propertyNamePart.Contains("["))
{
PropertyInfo pi = obj.GetType().GetProperty(propertyNamePart);
if (pi == null) return null;
obj = pi.GetValue(obj, null);
}
else
{ // propertyNamePart is areference to specific element
// (by index) inside a collection
// like AggregatedCollection[123]
// get collection name and element index
int indexStart = propertyNamePart.IndexOf("[")+1;
string collectionPropertyName = propertyNamePart.Substring(0, indexStart-1);
int collectionElementIndex = Int32.Parse(propertyNamePart.Substring(indexStart, propertyNamePart.Length-indexStart-1));
// get collection object
PropertyInfo pi = obj.GetType().GetProperty(collectionPropertyName);
if (pi == null) return null;
object unknownCollection = pi.GetValue(obj, null);
// try to process the collection as array
if (unknownCollection.GetType().IsArray)
{
object[] collectionAsArray = unknownCollection as object[];
obj = collectionAsArray[collectionElementIndex];
}
else
{
// try to process the collection as IList
System.Collections.IList collectionAsList = unknownCollection as System.Collections.IList;
if (collectionAsList != null)
{
obj = collectionAsList[collectionElementIndex];
}
else
{
// ??? Unsupported collection type
}
}
}
}
return obj;
}

If I use the code from Ed S. I get
'ReflectionExtensions.GetProperty(Type, string)' is inaccessible due to its protection level
It seems that GetProperty() is not available in Xamarin.Forms. TargetFrameworkProfile is Profile7 in my Portable Class Library (.NET Framework 4.5, Windows 8, ASP.NET Core 1.0, Xamarin.Android, Xamarin.iOS, Xamarin.iOS Classic).
Now I found a working solution:
using System.Linq;
using System.Reflection;
public static object GetPropValue(object source, string propertyName)
{
var property = source.GetType().GetRuntimeProperties().FirstOrDefault(p => string.Equals(p.Name, propertyName, StringComparison.OrdinalIgnoreCase));
return property?.GetValue(source);
}
Source

About the nested properties discussion, you can avoid all the reflection stuff if you use the DataBinder.Eval Method (Object, String) as below:
var value = DataBinder.Eval(DateTime.Now, "TimeOfDay.Hours");
Of course, you'll need to add a reference to the System.Web assembly, but this probably isn't a big deal.

The method to call has changed in .NET Standard (as of 1.6). Also we can use C# 6's null conditional operator.
using System.Reflection;
public static object GetPropValue(object src, string propName)
{
return src.GetType().GetRuntimeProperty(propName)?.GetValue(src);
}

The below method works perfect for me:
class MyClass {
public string prop1 { set; get; }
public object this[string propertyName]
{
get { return this.GetType().GetProperty(propertyName).GetValue(this, null); }
set { this.GetType().GetProperty(propertyName).SetValue(this, value, null); }
}
}
To get the property value:
MyClass t1 = new MyClass();
...
string value = t1["prop1"].ToString();
To set the property value:
t1["prop1"] = value;

public static List<KeyValuePair<string, string>> GetProperties(object item) //where T : class
{
var result = new List<KeyValuePair<string, string>>();
if (item != null)
{
var type = item.GetType();
var properties = type.GetProperties(BindingFlags.Public | BindingFlags.Instance);
foreach (var pi in properties)
{
var selfValue = type.GetProperty(pi.Name).GetValue(item, null);
if (selfValue != null)
{
result.Add(new KeyValuePair<string, string>(pi.Name, selfValue.ToString()));
}
else
{
result.Add(new KeyValuePair<string, string>(pi.Name, null));
}
}
}
return result;
}
This is a way to get all properties with their values in a List.

Using PropertyInfo of the System.Reflection namespace. Reflection compiles just fine no matter what property we try to access. The error will come up during run-time.
public static object GetObjProperty(object obj, string property)
{
Type t = obj.GetType();
PropertyInfo p = t.GetProperty("Location");
Point location = (Point)p.GetValue(obj, null);
return location;
}
It works fine to get the Location property of an object
Label1.Text = GetObjProperty(button1, "Location").ToString();
We'll get the Location : {X=71,Y=27}
We can also return location.X or location.Y on the same way.

public class YourClass
{
//Add below line in your class
public object this[string propertyName] => GetType().GetProperty(propertyName)?.GetValue(this, null);
public string SampleProperty { get; set; }
}
//And you can get value of any property like this.
var value = YourClass["SampleProperty"];

The following code is a Recursive method for displaying the entire hierarchy of all of the Property Names and Values contained in an object's instance. This method uses a simplified version of AlexD's GetPropertyValue() answer above in this thread. Thanks to this discussion thread, I was able to figure out how to do this!
For example, I use this method to show an explosion or dump of all of the properties in a WebService response by calling the method as follows:
PropertyValues_byRecursion("Response", response, false);
public static object GetPropertyValue(object srcObj, string propertyName)
{
if (srcObj == null)
{
return null;
}
PropertyInfo pi = srcObj.GetType().GetProperty(propertyName.Replace("[]", ""));
if (pi == null)
{
return null;
}
return pi.GetValue(srcObj);
}
public static void PropertyValues_byRecursion(string parentPath, object parentObj, bool showNullValues)
{
/// Processes all of the objects contained in the parent object.
/// If an object has a Property Value, then the value is written to the Console
/// Else if the object is a container, then this method is called recursively
/// using the current path and current object as parameters
// Note: If you do not want to see null values, set showNullValues = false
foreach (PropertyInfo pi in parentObj.GetType().GetTypeInfo().GetProperties())
{
// Build the current object property's namespace path.
// Recursion extends this to be the property's full namespace path.
string currentPath = parentPath + "." + pi.Name;
// Get the selected property's value as an object
object myPropertyValue = GetPropertyValue(parentObj, pi.Name);
if (myPropertyValue == null)
{
// Instance of Property does not exist
if (showNullValues)
{
Console.WriteLine(currentPath + " = null");
// Note: If you are replacing these Console.Write... methods callback methods,
// consider passing DBNull.Value instead of null in any method object parameters.
}
}
else if (myPropertyValue.GetType().IsArray)
{
// myPropertyValue is an object instance of an Array of business objects.
// Initialize an array index variable so we can show NamespacePath[idx] in the results.
int idx = 0;
foreach (object business in (Array)myPropertyValue)
{
if (business == null)
{
// Instance of Property does not exist
// Not sure if this is possible in this context.
if (showNullValues)
{
Console.WriteLine(currentPath + "[" + idx.ToString() + "]" + " = null");
}
}
else if (business.GetType().IsArray)
{
// myPropertyValue[idx] is another Array!
// Let recursion process it.
PropertyValues_byRecursion(currentPath + "[" + idx.ToString() + "]", business, showNullValues);
}
else if (business.GetType().IsSealed)
{
// Display the Full Property Path and its Value
Console.WriteLine(currentPath + "[" + idx.ToString() + "] = " + business.ToString());
}
else
{
// Unsealed Type Properties can contain child objects.
// Recurse into my property value object to process its properties and child objects.
PropertyValues_byRecursion(currentPath + "[" + idx.ToString() + "]", business, showNullValues);
}
idx++;
}
}
else if (myPropertyValue.GetType().IsSealed)
{
// myPropertyValue is a simple value
Console.WriteLine(currentPath + " = " + myPropertyValue.ToString());
}
else
{
// Unsealed Type Properties can contain child objects.
// Recurse into my property value object to process its properties and child objects.
PropertyValues_byRecursion(currentPath, myPropertyValue, showNullValues);
}
}
}

public static TValue GetFieldValue<TValue>(this object instance, string name)
{
var type = instance.GetType();
var field = type.GetFields(BindingFlags.NonPublic | BindingFlags.Static | BindingFlags.Instance).FirstOrDefault(e => typeof(TValue).IsAssignableFrom(e.FieldType) && e.Name == name);
return (TValue)field?.GetValue(instance);
}
public static TValue GetPropertyValue<TValue>(this object instance, string name)
{
var type = instance.GetType();
var field = type.GetProperties(BindingFlags.NonPublic | BindingFlags.Static | BindingFlags.Instance).FirstOrDefault(e => typeof(TValue).IsAssignableFrom(e.PropertyType) && e.Name == name);
return (TValue)field?.GetValue(instance);
}

Dim NewHandle As YourType = CType(Microsoft.VisualBasic.CallByName(ObjectThatContainsYourVariable, "YourVariableName", CallType), YourType)

Here is another way to find a nested property that doesn't require the string to tell you the nesting path. Credit to Ed S. for the single property method.
public static T FindNestedPropertyValue<T, N>(N model, string propName) {
T retVal = default(T);
bool found = false;
PropertyInfo[] properties = typeof(N).GetProperties();
foreach (PropertyInfo property in properties) {
var currentProperty = property.GetValue(model, null);
if (!found) {
try {
retVal = GetPropValue<T>(currentProperty, propName);
found = true;
} catch { }
}
}
if (!found) {
throw new Exception("Unable to find property: " + propName);
}
return retVal;
}
public static T GetPropValue<T>(object srcObject, string propName) {
return (T)srcObject.GetType().GetProperty(propName).GetValue(srcObject, null);
}

You never mention what object you are inspecting, and since you are rejecting ones that reference a given object, I will assume you mean a static one.
using System.Reflection;
public object GetPropValue(string prop)
{
int splitPoint = prop.LastIndexOf('.');
Type type = Assembly.GetEntryAssembly().GetType(prop.Substring(0, splitPoint));
object obj = null;
return type.GetProperty(prop.Substring(splitPoint + 1)).GetValue(obj, null);
}
Note that I marked the object that is being inspected with the local variable obj. null means static, otherwise set it to what you want. Also note that the GetEntryAssembly() is one of a few available methods to get the "running" assembly, you may want to play around with it if you are having a hard time loading the type.

Have a look at the Heleonix.Reflection library. You can get/set/invoke members by paths, or create a getter/setter (lambda compiled into a delegate) which is faster than reflection. For example:
var success = Reflector.Get(DateTime.Now, null, "Date.Year", out int value);
Or create a getter once and cache for reuse (this is more performant but might throw NullReferenceException if an intermediate member is null):
var getter = Reflector.CreateGetter<DateTime, int>("Date.Year", typeof(DateTime));
getter(DateTime.Now);
Or if you want to create a List<Action<object, object>> of different getters, just specify base types for compiled delegates (type conversions will be added into compiled lambdas):
var getter = Reflector.CreateGetter<object, object>("Date.Year", typeof(DateTime));
getter(DateTime.Now);

Although the original question was about how to get the value of the property using only a single string as the parameter, it makes a lot of sense here to use an Expression rather than simply a string to ensure that the caller never uses a hard coded property name. Here is a one line version with usage:
public static class Utils
...
public static TVal GetPropertyValue<T, TVal>(T t, Expression<Func<T, TVal>> x)
=> (TVal)((x.Body as MemberExpression)?.Member as PropertyInfo)!.GetValue(t);
...
var val = Utils.GetPropertyValue(foo, p => p.Bar);
Here is a slightly better version in terms of readability a error handling:
public static TVal GetPropertyValue<T, TVal>(T t, Expression<Func<T, TVal>> x)
{
var m = (x.Body as MemberExpression)?.Member;
var p = m as PropertyInfo;
if (null == p)
throw new ArgumentException($"Unknown property: {typeof(T).Name}.{(m?.Name??"???")}");
return (TVal)p.GetValue(t);
}
In short you pass in a lambda expression reading a property. The body of the lambda - the part on the right of the fat arrow - is a member expression from which you can get the member name and which you can cast to a PropertyInfo, provided the member is actually a Property and not, for instance, a method.
In the short version, the null forgiving operator - the ! in the expression - tells the compiler that the PropertyInfo will not be null. This is a big lie and you will get a NullReferenceException at runtime. The longer version gives you the name of the property if it manages to get it.
PS: Thanks to Oleg G. for the initial version of this code :)

shorter way ....
var a = new Test { Id = 1 , Name = "A" , date = DateTime.Now};
var b = new Test { Id = 1 , Name = "AXXX", date = DateTime.Now };
var compare = string.Join("",a.GetType().GetProperties().Select(x => x.GetValue(a)).ToArray())==
string.Join("",b.GetType().GetProperties().Select(x => x.GetValue(b)).ToArray());

jheddings and AlexD both wrote excellent answers on how to resolve property strings. I'd like to throw mine in the mix, since I wrote a dedicated library exactly for that purpose.
Pather.CSharp's main class is Resolver. Per default it can resolve properties, array and dictionary entries.
So, for example, if you have an object like this
var o = new { Property1 = new { Property2 = "value" } };
and want to get Property2, you can do it like this:
IResolver resolver = new Resolver();
var path = "Property1.Property2";
object result = r.Resolve(o, path);
//=> "value"
This is the most basic example of the paths it can resolve. If you want to see what else it can, or how you can extend it, just head to its Github page.

Here's what I got based on other answers. A little overkill on getting so specific with the error handling.
public static T GetPropertyValue<T>(object sourceInstance, string targetPropertyName, bool throwExceptionIfNotExists = false)
{
string errorMsg = null;
try
{
if (sourceInstance == null || string.IsNullOrWhiteSpace(targetPropertyName))
{
errorMsg = $"Source object is null or property name is null or whitespace. '{targetPropertyName}'";
Log.Warn(errorMsg);
if (throwExceptionIfNotExists)
throw new ArgumentException(errorMsg);
else
return default(T);
}
Type returnType = typeof(T);
Type sourceType = sourceInstance.GetType();
PropertyInfo propertyInfo = sourceType.GetProperty(targetPropertyName, returnType);
if (propertyInfo == null)
{
errorMsg = $"Property name '{targetPropertyName}' of type '{returnType}' not found for source object of type '{sourceType}'";
Log.Warn(errorMsg);
if (throwExceptionIfNotExists)
throw new ArgumentException(errorMsg);
else
return default(T);
}
return (T)propertyInfo.GetValue(sourceInstance, null);
}
catch(Exception ex)
{
errorMsg = $"Problem getting property name '{targetPropertyName}' from source instance.";
Log.Error(errorMsg, ex);
if (throwExceptionIfNotExists)
throw;
}
return default(T);
}

Here is my solution. It works also with COM objects and allows to access collection/array items from COM objects.
public static object GetPropValue(this object obj, string name)
{
foreach (string part in name.Split('.'))
{
if (obj == null) { return null; }
Type type = obj.GetType();
if (type.Name == "__ComObject")
{
if (part.Contains('['))
{
string partWithoundIndex = part;
int index = ParseIndexFromPropertyName(ref partWithoundIndex);
obj = Versioned.CallByName(obj, partWithoundIndex, CallType.Get, index);
}
else
{
obj = Versioned.CallByName(obj, part, CallType.Get);
}
}
else
{
PropertyInfo info = type.GetProperty(part);
if (info == null) { return null; }
obj = info.GetValue(obj, null);
}
}
return obj;
}
private static int ParseIndexFromPropertyName(ref string name)
{
int index = -1;
int s = name.IndexOf('[') + 1;
int e = name.IndexOf(']');
if (e < s)
{
throw new ArgumentException();
}
string tmp = name.Substring(s, e - s);
index = Convert.ToInt32(tmp);
name = name.Substring(0, s - 1);
return index;
}

Whenever you want to loop over all properties in on an object and then use each value of the property must use this piece of code:
foreach (var property in request.GetType().GetProperties())
{
var valueOfProperty = property.GetValue(properties, null);
}

How to get a property value using Reflection if the property name is defined as "name"

I have the following code to compare two collections to one another...
//code invocation
CollectionComparer comp = new CollectionComparer("name", "ASC");
this.InnerList.Sort(comp);
class
public class CollectionComparer : IComparer
{
private String _property;
private String _order;
public CollectionComparer(String Property, String Order)
{
this._property = Property;
this._order = Order;
}
public int Compare(object obj1, object obj2)
{
int returnValue;
Type type = obj1.GetType();
PropertyInfo propertie1 = type.GetProperty(_property); // returns null here
Type type2 = obj2.GetType();
PropertyInfo propertie2 = type2.GetProperty(_property); // returns null here
object finalObj1 = propertie1.GetValue(obj1, null); // Null Reference Exception thrown here, because propertie1 is null
object finalObj2 = propertie2.GetValue(obj2, null);
IComparable Ic1 = finalObj1 as IComparable;
IComparable Ic2 = finalObj2 as IComparable;
if (_order == "ASC")
{
returnValue = Ic1.CompareTo(Ic2);
}
else
{
returnValue = Ic2.CompareTo(Ic1);
}
return returnValue;
}
}
The code seems to work fine, except when I try to sort a property called "name". When comparing that property both the variables propertie1 and propertie2 are null, and the code throws an exception because of that.
So my question is how to use reflection to get the value of a property with the name of "name"?

By the way, is _property variable set?
How about this extension method:
public static object GetProperty(this object instance, string name)
{
if (instance == null)
throw new ArgumentNullException("instance");
if (name == null)
throw new ArgumentNullException("name");
Type type = instance.GetType();
PropertyInfo property = type.GetProperty(name, BindingFlags.Public | BindingFlags.Instance);
if (property == null)
throw new InvalidOperationException(string.Format("Type {0} does not have a property {1}", type, name));
object result = property.GetValue(instance, null);
return result;
}

Ok, I figured it out... I guess uppercase counts when doing reflection...
I needed to change the code invocation to...
//code invocation
CollectionComparer comp = new CollectionComparer("Name", "ASC");
this.InnerList.Sort(comp);
As the property was actually called "Name" and not "name"

Propertyinfo not getting property of string

I am facing a problem about PropertyInfo .My code is here
Type type = typeof(T);
PropertyInfo propertyInfo = type.GetProperty(filterDescriptor.Member);
if (propertyInfo != null && propertyInfo.PropertyType.FullName.ToLower() == "system.string")
{
isMemberStringType = true;
filterDescriptor.Value = filterDescriptor.Value ?? string.Empty;
}
Problem is propertyInfo getting NULL if filterDescriptor.Member contains value like
abc.key
abc.Name
But when it contains Just Key and Name ,It works,it get system.string and execute if .How do i over come this.Help.

MSDN documentation makes it very clear:
Parameters
name
Type: System.String
The string containing the name of the public property to get.
No class can contain property with dot (.) in name.
What you are trying to achieve (I think) is to check child property (e.g. your class has property named abc and class of that property has its own property named key).
To do so, you have to use recursion.
public bool HasPropertyInPath(
Type checkedType,
string propertyPath,
Type propertyType)
{
int dotIndex = propertyPath.IndexOf('.');
if (dotIndex != -1)
{
PropertyInfo topPropertyInfo
= checkedType.GetProperty(propertyPath.Substring(0, dotIndex));
if (topPropertyInfo == null)
{
return false;
}
return HasPropertyInPath(
topPropertyInfo.PropertyType,
propertyPath.Substring(dotIndex + 1),
propertyType);
}
PropertyInfo propertyInfo = checkedType.GetProperty(propertyPath);
return (propertyInfo != null && propertyInfo.PropertyType == propertyType);
}
Then you can use it like this:
if (HasPropertyInPath(typeof(T), filterDescriptor.Member, typeof(string))
{
isMemberStringType = true;
filterDescriptor.Value = filterDescriptor.Value ?? string.Empty;
}
Above code is not tested but should check children properties.

This is not possible with simple call of GetProperty because it works only for the current object level. What you want to do is to traverse nested properties. And you should to remember about treating collections differently (because you want to see their elements properties, not the properties of the collection itself):
static System.Reflection.PropertyInfo GetProperty(Type type, string propertyPath)
{
System.Reflection.PropertyInfo result = null;
string[] pathSteps = propertyPath.Split('.');
Type currentType = type;
for (int i = 0; i < pathSteps.Length; ++i)
{
string currentPathStep = pathSteps[i];
result = currentType.GetProperty(currentPathStep);
if (result.PropertyType.IsArray)
{
currentType = result.PropertyType.GetElementType();
}
else
{
currentType = result.PropertyType;
}
}
return result;
}
and then you can 'query' objects with 'paths':
PropertyInfo pi = GetProperty(c1.GetType(), "ArrayField1.Char");
PropertyInfo pi2 = GetProperty(c2.GetType(), "Color");
See more for reference in this answer.

How to set Vaues to the Nested Property using C# Reflection.?

I am trying to set a value to a Nested Property of Class dynamically using reflection. Could anyone help me to do this.
I am having a class Region like below.
public class Region
{
public int id;
public string name;
public Country CountryInfo;
}
public class Country
{
public int id;
public string name;
}
I have a Oracle Data reader to provide the Values from the Ref cursor.
which will give me as
Id,name,Country_id,Country_name
I could able to assign the values to the Region.Id, Region.Name by below.
FieldName="id"
prop = objItem.GetType().GetProperty(FieldName, BindingFlags.Public | BindingFlags.Instance);
prop.SetValue(objItem, Utility.ToLong(reader_new[ResultName]), null);
And for the Nested Property I could able to do the assign values to the as below by creating a Instance by reading the Fieldname.
FieldName="CountryInfo.id"
if (FieldName.Contains('.'))
{
Object NestedObject = objItem.GetType().GetProperty(Utility.Trim(FieldName.Split('.')[0]), BindingFlags.Public | BindingFlags.Instance);
//getting the Type of NestedObject
Type NestedObjectType = NestedObject.GetType();
//Creating Instance
Object Nested = Activator.CreateInstance(typeNew);
//Getting the nested Property
PropertyInfo nestedpropinfo = objItem.GetType().GetProperty(Utility.Trim(FieldName.Split('.')[0]), BindingFlags.Public | BindingFlags.Instance);
PropertyInfo[] nestedpropertyInfoArray = nestedpropinfo.PropertyType.GetProperties();
prop = nestedpropertyInfoArray.Where(p => p.Name == Utility.Trim(FieldName.Split('.')[1])).SingleOrDefault();
prop.SetValue(Nested, Utility.ToLong(reader_new[ResultName]), null);
Nestedprop = objItem.GetType().GetProperty(Utility.Trim(FieldName.Split('.')[0]), BindingFlags.Public | BindingFlags.Instance);
Nestedprop.SetValue(objItem, Nested, null);
}
The above assign values to Country.Id.
But Since I am creating instance each and every time I could not able to get the previous Country.Id value if I go for the Next Country.Name.
Could anybody tell could to assign values to the objItem(that is Region).Country.Id and objItem.Country.Name. Which means how to assign values to the Nested Properties instead of creating instance and assigning everytime.
Thanks in advance.!

You should be calling PropertyInfo.GetValue using the Country property to get the country, then PropertyInfo.SetValue using the Id property to set the ID on the country.
So something like this:
public void SetProperty(string compoundProperty, object target, object value)
{
string[] bits = compoundProperty.Split('.');
for (int i = 0; i < bits.Length - 1; i++)
{
PropertyInfo propertyToGet = target.GetType().GetProperty(bits[i]);
target = propertyToGet.GetValue(target, null);
}
PropertyInfo propertyToSet = target.GetType().GetProperty(bits.Last());
propertyToSet.SetValue(target, value, null);
}

Get Nest properties e.g., Developer.Project.Name
private static System.Reflection.PropertyInfo GetProperty(object t, string PropertName)
{
if (t.GetType().GetProperties().Count(p => p.Name == PropertName.Split('.')[0]) == 0)
throw new ArgumentNullException(string.Format("Property {0}, is not exists in object {1}", PropertName, t.ToString()));
if (PropertName.Split('.').Length == 1)
return t.GetType().GetProperty(PropertName);
else
return GetProperty(t.GetType().GetProperty(PropertName.Split('.')[0]).GetValue(t, null), PropertName.Split('.')[1]);
}

Expanding on Jon Skeets answer, if the value you're getting is null and you want to create an object for that type:
public void SetProperty(string compoundProperty, object target, object value)
{
var bits = compoundProperty.Split('.');
for (var i = 0; i < bits.Length - 1; i++) {
var propertyToGet = target.GetType().GetProperty(bits[i]);
var propertyValue = propertyToGet.GetValue(target, null);
if (propertyValue == null) {
propertyValue = Activator.CreateInstance(propertyToGet.PropertyType);
propertyToGet.SetValue(target, propertyValue);
}
target = propertyToGet.GetValue(target, null);
}
var propertyToSet = target.GetType().GetProperty(bits.Last());
propertyToSet.SetValue(target, value, null);
}

Expanding on Luke Garrigan Answer:
If you want to have it working also with non lists too:
public void SetProperty(string compoundProperty, object target, object value)
{
var bits = compoundProperty.Split('.');
if(bits == null) bits = new string[1]{compoundProperty};
for (var i = 0; i < bits.Length - 1; i++) {
var propertyToGet = target.GetType().GetProperty(bits[i]);
var propertyValue = propertyToGet.GetValue(target, null);
if (propertyValue == null) {
propertyValue = Activator.CreateInstance(propertyToGet.PropertyType);
propertyToGet.SetValue(target, propertyValue);
}
target = propertyToGet.GetValue(target, null);
}
var propertyToSet = target.GetType().GetProperty(bits.Last());
propertyToSet.SetValue(target, value, null);
}

Using reflection in C# to get properties of a nested object

Given the following objects:
public class Customer {
public String Name { get; set; }
public String Address { get; set; }
}
public class Invoice {
public String ID { get; set; }
public DateTime Date { get; set; }
public Customer BillTo { get; set; }
}
I'd like to use reflection to go through the Invoice to get the Name property of a Customer. Here's what I'm after, assuming this code would work:
Invoice inv = GetDesiredInvoice(); // magic method to get an invoice
PropertyInfo info = inv.GetType().GetProperty("BillTo.Address");
Object val = info.GetValue(inv, null);
Of course, this fails since "BillTo.Address" is not a valid property of the Invoice class.
So, I tried writing a method to split the string into pieces on the period, and walk the objects looking for the final value I was interested in. It works okay, but I'm not entirely comfortable with it:
public Object GetPropValue(String name, Object obj) {
foreach (String part in name.Split('.')) {
if (obj == null) { return null; }
Type type = obj.GetType();
PropertyInfo info = type.GetProperty(part);
if (info == null) { return null; }
obj = info.GetValue(obj, null);
}
return obj;
}
Any ideas on how to improve this method, or a better way to solve this problem?
EDIT after posting, I saw a few related posts... There doesn't seem to be an answer that specifically addresses this question, however. Also, I'd still like the feedback on my implementation.

I use following method to get the values from (nested classes) properties like
"Property"
"Address.Street"
"Address.Country.Name"
public static object GetPropertyValue(object src, string propName)
{
if (src == null) throw new ArgumentException("Value cannot be null.", "src");
if (propName == null) throw new ArgumentException("Value cannot be null.", "propName");
if(propName.Contains("."))//complex type nested
{
var temp = propName.Split(new char[] { '.' }, 2);
return GetPropertyValue(GetPropertyValue(src, temp[0]), temp[1]);
}
else
{
var prop = src.GetType().GetProperty(propName);
return prop != null ? prop.GetValue(src, null) : null;
}
}
Here is the Fiddle: https://dotnetfiddle.net/PvKRH0

I know I'm a bit late to the party, and as others said, your implementation is fine
...for simple use cases.
However, I've developed a library that solves exactly that use case, Pather.CSharp.
It is also available as Nuget Package.
Its main class is Resolver with its Resolve method.
You pass it an object and the property path, and it will return the desired value.
Invoice inv = GetDesiredInvoice(); // magic method to get an invoice
var resolver = new Resolver();
object result = resolver.Resolve(inv, "BillTo.Address");
But it can also resolve more complex property paths, including array and dictionary access.
So, for example, if your Customer had multiple addresses
public class Customer {
public String Name { get; set; }
public IEnumerable<String> Addresses { get; set; }
}
you could access the second one using Addresses[1].
Invoice inv = GetDesiredInvoice(); // magic method to get an invoice
var resolver = new Resolver();
object result = resolver.Resolve(inv, "BillTo.Addresses[1]");

I actually think your logic is fine. Personally, I would probably change it around so you pass the object as the first parameter (which is more inline with PropertyInfo.GetValue, so less surprising).
I also would probably call it something more like GetNestedPropertyValue, to make it obvious that it searches down the property stack.

You have to access the ACTUAL object that you need to use reflection on. Here is what I mean:
Instead of this:
Invoice inv = GetDesiredInvoice(); // magic method to get an invoice
PropertyInfo info = inv.GetType().GetProperty("BillTo.Address");
Object val = info.GetValue(inv, null);
Do this (edited based on comment):
Invoice inv = GetDesiredInvoice(); // magic method to get an invoice
PropertyInfo info = inv.GetType().GetProperty("BillTo");
Customer cust = (Customer)info.GetValue(inv, null);
PropertyInfo info2 = cust.GetType().GetProperty("Address");
Object val = info2.GetValue(cust, null);
Look at this post for more information:
Using reflection to set a property of a property of an object

In hopes of not sounding too late to the party, I would like to add my solution:
Definitely use recursion in this situation
public static Object GetPropValue(String name, object obj, Type type)
{
var parts = name.Split('.').ToList();
var currentPart = parts[0];
PropertyInfo info = type.GetProperty(currentPart);
if (info == null) { return null; }
if (name.IndexOf(".") > -1)
{
parts.Remove(currentPart);
return GetPropValue(String.Join(".", parts), info.GetValue(obj, null), info.PropertyType);
} else
{
return info.GetValue(obj, null).ToString();
}
}

You don't explain the source of your "discomfort," but your code basically looks sound to me.
The only thing I'd question is the error handling. You return null if the code tries to traverse through a null reference or if the property name doesn't exist. This hides errors: it's hard to know whether it returned null because there's no BillTo customer, or because you misspelled it "BilTo.Address"... or because there is a BillTo customer, and its Address is null! I'd let the method crash and burn in these cases -- just let the exception escape (or maybe wrap it in a friendlier one).

Here is another implementation that will skip a nested property if it is an enumerator and continue deeper. Properties of type string are not affected by the Enumeration Check.
public static class ReflectionMethods
{
public static bool IsNonStringEnumerable(this PropertyInfo pi)
{
return pi != null && pi.PropertyType.IsNonStringEnumerable();
}
public static bool IsNonStringEnumerable(this object instance)
{
return instance != null && instance.GetType().IsNonStringEnumerable();
}
public static bool IsNonStringEnumerable(this Type type)
{
if (type == null || type == typeof(string))
return false;
return typeof(IEnumerable).IsAssignableFrom(type);
}
public static Object GetPropValue(String name, Object obj)
{
foreach (String part in name.Split('.'))
{
if (obj == null) { return null; }
if (obj.IsNonStringEnumerable())
{
var toEnumerable = (IEnumerable)obj;
var iterator = toEnumerable.GetEnumerator();
if (!iterator.MoveNext())
{
return null;
}
obj = iterator.Current;
}
Type type = obj.GetType();
PropertyInfo info = type.GetProperty(part);
if (info == null) { return null; }
obj = info.GetValue(obj, null);
}
return obj;
}
}
based on this question and on
How to know if a PropertyInfo is a collection
by Berryl
I use this in a MVC project to dynamically Order my data by simply passing the Property to sort by
Example:
result = result.OrderBy((s) =>
{
return ReflectionMethods.GetPropValue("BookingItems.EventId", s);
}).ToList();
where BookingItems is a list of objects.

> Get Nest properties e.g., Developer.Project.Name
private static System.Reflection.PropertyInfo GetProperty(object t, string PropertName)
{
if (t.GetType().GetProperties().Count(p => p.Name == PropertName.Split('.')[0]) == 0)
throw new ArgumentNullException(string.Format("Property {0}, is not exists in object {1}", PropertName, t.ToString()));
if (PropertName.Split('.').Length == 1)
return t.GetType().GetProperty(PropertName);
else
return GetProperty(t.GetType().GetProperty(PropertName.Split('.')[0]).GetValue(t, null), PropertName.Split('.')[1]);
}

if (info == null) { /* throw exception instead*/ }
I would actually throw an exception if they request a property that doesn't exist. The way you have it coded, if I call GetPropValue and it returns null, I don't know if that means the property didn't exist, or the property did exist but it's value was null.

public static string GetObjectPropertyValue(object obj, string propertyName)
{
bool propertyHasDot = propertyName.IndexOf(".") > -1;
string firstPartBeforeDot;
string nextParts = "";
if (!propertyHasDot)
firstPartBeforeDot = propertyName.ToLower();
else
{
firstPartBeforeDot = propertyName.Substring(0, propertyName.IndexOf(".")).ToLower();
nextParts = propertyName.Substring(propertyName.IndexOf(".") + 1);
}
foreach (var property in obj.GetType().GetProperties())
if (property.Name.ToLower() == firstPartBeforeDot)
if (!propertyHasDot)
if (property.GetValue(obj, null) != null)
return property.GetValue(obj, null).ToString();
else
return DefaultValue(property.GetValue(obj, null), propertyName).ToString();
else
return GetObjectPropertyValue(property.GetValue(obj, null), nextParts);
throw new Exception("Property '" + propertyName.ToString() + "' not found in object '" + obj.ToString() + "'");
}

I wanted to share my solution although it may be too late. This solution is primarily to check if the nested property exists. But it can be easily tweaked to return the property value if needed.
private static PropertyInfo _GetPropertyInfo(Type type, string propertyName)
{
//***
//*** Check if the property name is a complex nested type
//***
if (propertyName.Contains("."))
{
//***
//*** Get the first property name of the complex type
//***
var tempPropertyName = propertyName.Split(".", 2);
//***
//*** Check if the property exists in the type
//***
var prop = _GetPropertyInfo(type, tempPropertyName[0]);
if (prop != null)
{
//***
//*** Drill down to check if the nested property exists in the complex type
//***
return _GetPropertyInfo(prop.PropertyType, tempPropertyName[1]);
}
else
{
return null;
}
}
else
{
return type.GetProperty(propertyName, BindingFlags.IgnoreCase | BindingFlags.Public | BindingFlags.Instance);
}
}
I had to refer to few posts to come up with this solution. I think this will work for multiple nested property types.

My internet connection was down when I need to solve the same problem, so I had to 're-invent the wheel':
static object GetPropertyValue(Object fromObject, string propertyName)
{
Type objectType = fromObject.GetType();
PropertyInfo propInfo = objectType.GetProperty(propertyName);
if (propInfo == null && propertyName.Contains('.'))
{
string firstProp = propertyName.Substring(0, propertyName.IndexOf('.'));
propInfo = objectType.GetProperty(firstProp);
if (propInfo == null)//property name is invalid
{
throw new ArgumentException(String.Format("Property {0} is not a valid property of {1}.", firstProp, fromObject.GetType().ToString()));
}
return GetPropertyValue(propInfo.GetValue(fromObject, null), propertyName.Substring(propertyName.IndexOf('.') + 1));
}
else
{
return propInfo.GetValue(fromObject, null);
}
}
Pretty sure this solves the problem for any string you use for property name, regardless of extent of nesting, as long as everything's a property.

Based on the original code from #jheddings, I have created a extension method version with generic type and verifications:
public static T GetPropertyValue<T>(this object sourceObject, string propertyName)
{
if (sourceObject == null) throw new ArgumentNullException(nameof(sourceObject));
if (string.IsNullOrWhiteSpace(propertyName)) throw new ArgumentException(nameof(propertyName));
foreach (string currentPropertyName in propertyName.Split('.'))
{
if (string.IsNullOrWhiteSpace(currentPropertyName)) throw new InvalidOperationException($"Invalid property '{propertyName}'");
PropertyInfo propertyInfo = sourceObject.GetType().GetProperty(currentPropertyName);
if (propertyInfo == null) throw new InvalidOperationException($"Property '{currentPropertyName}' not found");
sourceObject = propertyInfo.GetValue(sourceObject);
}
return sourceObject is T result ? result : default;
}

I wrote a method that received one object type as the argument from the input and returns dictionary<string,string>
public static Dictionary<string, string> GetProperties(Type placeHolderType)
{
var result = new Dictionary<string, string>();
var properties = placeHolderType.GetProperties();
foreach (var propertyInfo in properties)
{
string name = propertyInfo.Name;
string description = GetDescriptionTitle(propertyInfo);
if (IsNonString(propertyInfo.PropertyType))
{
var list = GetProperties(propertyInfo.PropertyType);
foreach (var item in list)
{
result.Add($"{propertyInfo.PropertyType.Name}_{item.Key}", item.Value);
}
}
else
{
result.Add(name, description);
}
}
return result;
}
public static bool IsNonString(Type type)
{
if (type == null || type == typeof(string))
return false;
return typeof(IPlaceHolder).IsAssignableFrom(type);
}
private static string GetDescriptionTitle(MemberInfo memberInfo)
{
if (Attribute.GetCustomAttribute(memberInfo, typeof(DescriptionAttribute)) is DescriptionAttribute descriptionAttribute)
{
return descriptionAttribute.Description;
}
return memberInfo.Name;
}

public static object GetPropertyValue(object src, string propName)
{
if (src == null) throw new ArgumentException("Value cannot be null.", "src");
if (propName == null) throw new ArgumentException("Value cannot be null.", "propName");
var prop = src.GetType().GetProperty(propName);
if (prop != null)
{
return prop.GetValue(src, null);
}
else
{
var props = src.GetType().GetProperties();
foreach (var property in props)
{
var propInfo = src.GetType().GetProperty(property.Name);
if (propInfo != null)
{
var propVal = propInfo.GetValue(src, null);
if (src.GetType().GetProperty(property.Name).PropertyType.IsClass)
{
return GetPropertyValue(propVal, propName);
}
return propVal;
}
}
return null;
}
usage: calling part
var emp = new Employee() { Person = new Person() { FirstName = "Ashwani" } };
var val = GetPropertyValue(emp, "FirstName");
above can search the property value at any level

Try inv.GetType().GetProperty("BillTo+Address");