AmbiguousMatchException - Type.GetProperty - C# Reflection - c#

Yesterday I ran into an Issue while developing a Web Part (This question is not about webpart but about C#). Little background about the Issue. I have a code that load the WebPart using the Reflection, In which I got the AmbiguousMatchException. To reproduce it try the below code
public class TypeA
{
public virtual int Height { get; set; }
}
public class TypeB : TypeA
{
public String Height { get; set; }
}
public class Class1 : TypeB
{
}
Assembly oAssemblyCurrent = Assembly.GetExecutingAssembly();
Type oType2 = oAssemblyCurrent.GetType("AmbigousMatchReflection.Class1");
PropertyInfo oPropertyInfo2 = oType2.GetProperty("Height");//Throws AmbiguousMatchException
oPropertyInfo2 = oType2.GetProperty("Height",
BindingFlags.DeclaredOnly | BindingFlags.Public | BindingFlags.Instance); // I tried this code Neither these BindingFlags or any other didnt help
I wanted to know the BindingFlag to Fetch the Height Property. You will have the question of why I wanted to create another Height Property that is already there in the Base class. That is how the Microsoft.SharePoint.WebPartPages.PageViewerWebPart was designed check the Height property of the PageViewerWebPart class.

There are two Height properties there, and neither of them are declared by Class1 which you're calling GetProperty on.
Now, would it be fair to say you're looking for "the Height property declared as far down the type hiearchy as possible"? If so, here's some code to find it:
using System;
using System.Diagnostics;
using System.Reflection;
public class TypeA
{
public virtual int Height { get; set; }
}
public class TypeB : TypeA
{
public new String Height { get; set; }
}
public class Class1 : TypeB
{
}
class Test
{
static void Main()
{
Type type = typeof(Class1);
Console.WriteLine(GetLowestProperty(type, "Height").DeclaringType);
}
static PropertyInfo GetLowestProperty(Type type, string name)
{
while (type != null)
{
var property = type.GetProperty(name, BindingFlags.DeclaredOnly |
BindingFlags.Public |
BindingFlags.Instance);
if (property != null)
{
return property;
}
type = type.BaseType;
}
return null;
}
}
Note that if you know the return types will be different, it may be worth simplifying the code as shown in sambo99's answer. That would make it quite brittle though - changing the return type later could then cause bugs which would only be found at execution time. Ouch. I'd say that by the time you've done this you're in a brittle situation anyway :)

See the following example:
class Foo {
public float Height { get; set; }
}
class Bar : Foo {
public int Height { get; set; }
}
class BarBar : Bar { }
class Foo2 : Foo{
public float Height { get; set; }
}
class BarBar2 : Foo2 { }
static void Main(string[] args) {
// works
var p = typeof(BarBar).GetProperty("Height", typeof(float), Type.EmptyTypes);
// works
var p2 = typeof(BarBar).BaseType.GetProperty("Height", BindingFlags.DeclaredOnly | BindingFlags.Public | BindingFlags.Instance);
// works
var p3 = typeof(BarBar2).GetProperty("Height");
// fails
var p4 = typeof(BarBar).GetProperty("Height");
Console.WriteLine(p);
}
You get an AmbiguousMatchException if a two or more properties with the differing return types and the same name live in your inheritance chain.
Stuff resolves just fine if you override an implementation (using new or override) and maintain the return type.
You can force reflection only to look at the properties for a particular type.

Obviously there are two properties that match the name you have given of "Height", one with return type int, and another string., Just add the return type as the second parameter tot the GetPropertyCall depending on which you want returning and this ambiguity should disappear.

I created two extension methods extending on Jon Skeet's answer. You can place those in any public static class.
Edit: Removed the MissingMemberException to behave more like the default .NET implementations which return null on failure.
Usage:
var field = type.GetFieldUnambiguous(type, "FieldName", bindingFlags);
var property = type.GetPropertyUnambiguous(type, "PropertyName", bindingFlags);
Implementation:
public static FieldInfo GetFieldUnambiguous(this Type type, string name, BindingFlags flags)
{
if (type == null) throw new ArgumentNullException(nameof(type));
if (name == null) throw new ArgumentNullException(nameof(name));
flags |= BindingFlags.DeclaredOnly;
while (type != null)
{
var field = type.GetField(name, flags);
if (field != null)
{
return field;
}
type = type.BaseType;
}
return null;
}
public static PropertyInfo GetPropertyUnambiguous(this Type type, string name, BindingFlags flags
{
if (type == null) throw new ArgumentNullException(nameof(type));
if (name == null) throw new ArgumentNullException(nameof(name));
flags |= BindingFlags.DeclaredOnly;
while (type != null)
{
var property = type.GetProperty(name, flags);
if (property != null)
{
return property;
}
type = type.BaseType;
}
return null;
}

Related

Dealing with derived properties with same name as in base class using reflection

I will try to explain my best, but it is a tricky one to explain.
I am having a problem using reflection when a derived object redefines a property already in a base class.
Let's consider the following classes to start with:
// The base class
namespace MyNamesapce
{
public abstract class MyClassBase: IMyClassBase
{
[JsonConstructor]
public MyClassBase()
{
}
public string Info { get; set; }
public string Unit { get; set; }
public string Name { get; set; }
}
}
// MyClassArray is most of the time used
namespace MyNamesapce
{
public class MyClassArray<TType> : MyClassBase, IMyClassArray<TType>
{
public MyClassArray()
{
}
[JsonConstructor]
public MyClassArray(IEnumerable<TType> value, TType minValue, TType maxValue)
{
MinValue = minValue;
MaxValue = maxValue;
Value = value;
}
public IEnumerable<TType> Value { get; set; }
public TType MinValue { get; set; }
public TType MaxValue { get; set; }
}
}
// In some rare cases we need 2D arrays
namespace MyNamesapce
{
public class MyClass2DArray<TType> : MyClassArray<TType>, IMyClass2DArray<TType>
{
private int[] _arraySize { get; set; }
public MyClass2DArray()
{
}
[JsonConstructor]
public MyClass2DArray(TType[][] value, TType minValue, TType maxValue)
{
MinValue = minValue;
MaxValue = maxValue;
_arraySize = new int[2] { value.Count(), value[0].Length };
Value = value;
}
public new TType[][] Value
{
get
{
TType[][] array2D = new TType[_arraySize[0]][];
// Reconstruct the 2D array
TType[] tmpArray;
int startIdx = 0;
for (int numArrays = 0; numArrays < _arraySize[0]; numArrays++)
{
tmpArray = new TType[_arraySize[1]];
Array.Copy(base.Value.ToArray(), startIdx, tmpArray, 0, _arraySize[1]);
startIdx += _arraySize[1];
array2D[numArrays] = tmpArray;
}
return array2D;
}
set
{
// Should not be able to set _value to null
if (value == null)
return;
base.Value = value.SelectMany(v => v).ToArray();
}
}
}
}
I now need to get all the properties from all instances of MyClassArray and MyClassArray2D. You will say, there are plenty of threads discussing that very point, just use "GetType().GetProperties()" for the former and use "GetType().GetProperty(..., BindingFlags.Instance | BindingFlags.Public | BindingFlags.DeclaredOnly)" for the latter.
The problem is that I do not know in advance which class is being processed. In my system when deserialising a Json, instances of both MyClassArray and MyClassArray2D have to be reconstructed, which is done using the following setter:
public static void SetProperty(this Object obj, string propName, Object value)
{
PropertyInfo info = null;
object[] indexer = null;
string[] nameParts = propName.Split('.');
if (obj == null) { return; }
var props = obj.GetType().GetProperties();
for (int idx = 0; idx < nameParts.Count() - 1; idx++)
{
try
{
indexer = null;
// Try to access normal property
info = obj.GetType().GetProperty(nameParts[idx]);
if (info == null)
continue;
obj = info.GetValue(obj, indexer);
}
catch
{
info = null;
indexer = null;
}
}
if (obj != null)
{
// !!! Note that here, using declare only will only work when using derived classes
PropertyInfo propertyToSet = obj.GetType().GetProperty(nameParts.Last(), BindingFlags.Instance | BindingFlags.Public | BindingFlags.DeclaredOnly); // | BindingFlags.DeclaredOnly);
propertyToSet?.SetValue(obj, value);
}
else
{
throw new SystemException($"Could not find the property {propName}");
}
}
As you can see an object is passed in to SetProperty() (that can be of any type).
When it is of type MyClassArray, there are no problems, but if it is of type MyClassArray2D it does not quite work as the latter redefines "Value", which will break the logic as 2 properties called value will exist. I need a way to detect that.
The first loop seems to do the right thing. "obj = info.GetValue(obj, indexer);" will return "obj" containing all the versions of "Value". The problem is in the next part of SetProperty().
How can I detect when more than one "Value" property is in "obj"? And how to always pick the derived version of "Value"?
Also if I just use "BindingFlags.DeclaredOnly" as done here in my code snipet, properties from the base class get lost/disappear, which is undesirable.
Is there maybe a way to return in "obj" all the properties without the duplicates coming from the base class? Or some kind of property filter maybe?

Finding correct property implementing an interface

So, I thaught I have a solution for getting a PropertyInfo when having a concrete class, and a PropertyInfo for an interface implemented by the concrete class. Here is the code:
public static PropertyInfo GetImplementingProperty(Type concreteType, PropertyInfo interfaceProperty)
{
// do some region parameter check, skipped
var interfaceType = interfaceProperty.DeclaringType;
//use the set method if we have a write only property
var getCorrectMethod = interfaceProperty.GetGetMethod() == null
? (Func<PropertyInfo, MethodInfo>) (p => p.GetSetMethod(true))
: p => p.GetGetMethod(true);
var propertyMethod = getCorrectMethod(interfaceProperty);
var mapping = concreteType.GetInterfaceMap(interfaceType);
MethodInfo targetMethod = null;
for (var i = 0; i < mapping.InterfaceMethods.Length; i++)
{
if (mapping.InterfaceMethods[i] == propertyMethod)
{
targetMethod = mapping.TargetMethods[i];
break;
}
}
foreach (var property in concreteType.GetProperties(
BindingFlags.Instance | BindingFlags.GetProperty |
BindingFlags.Public | BindingFlags.NonPublic)) // include non-public!
{
if (targetMethod == getCorrectMethod(property)) // include non-public!
{
return property;
}
}
throw new InvalidOperationException("The property {0} defined on the interface {1} has not been found on the class {2}. That should never happen."
.FormatText(interfaceProperty.Name, interfaceProperty.DeclaringType.FullName, concreteType.FullName));
}
Unfortunately I found a case where it fails, and I am unsure how to fix this.
So I have in a dll a class:
public abstract class BaseClass
{
public Guid ConfigId { get; set; }
public virtual Guid ConfigId2 { get; set; }
}
Then in another dll I do:
interface INamed
{
Guid ConfigId { get; }
Guid ConfigId2 { get; }
}
private class SuperClass : BaseClass, INamed
{
}
Now
ReflectionHelper.GetImplementingProperty(typeof(SuperClass), typeof(INamed).GetProperty("ConfigId2")); // this works
ReflectionHelper.GetImplementingProperty(typeof(SuperClass), typeof(INamed).GetProperty("ConfigId")); // this fails
Any idea how do I match up the ConfigId property to the Base class proprety definition?
PS. I have attributes on the concrete class properties, thats why i need to get those.
Any help appreciated!
You need to add BindingFlags.FlattenHierarchy to your GetProperties call in order to get parent class properties. See the documentation at https://msdn.microsoft.com/en-us/library/kyaxdd3x(v=vs.110).aspx

Getting the DisplayNameAttribute from an Internal class

I have a class that is declared Internal. It is decorated with various annotations. In particular is the [DisplayName("My Display Name")] annotation. I have some code that will retrieve the value but only works if the class is declared public. I am sort of new to using reflection. I believe I need to specify that the BindingFlags.NonPublic be used but I am not sure where.
LinqPAD code:
void Main()
{
List<SpGetProfileInfoResult> p = new List<SpGetProfileInfoResult>();
p.Add(new SpGetProfileInfoResult() { FName = "Eric" });
p.Add(new SpGetProfileInfoResult() { FName = "Mike" });
p.Dump();
foreach (var item in p)
{
Console.WriteLine(item.DisplayName(i => i.FName));
Console.WriteLine(item.FName);
}
}
public partial class SpGetProfileInfoResult
{
// Uncomment this annotation to see that this part will work
// [System.ComponentModel.DisplayNameAttribute("[BILLTO-FNAME]")]
public string FName { get; set; }
}
public partial class SpGetProfileInfoResult
{
internal class Metadata
{
// This attribute is never available seems.
[System.ComponentModel.DisplayNameAttribute("[BILL-FNAME]")]
public string FName { get; set; }
}
}
public static class Tag
{
public static T GetAttribute<T>(this MemberInfo member, bool isRequired) where T : Attribute
{
var attribute = member.GetCustomAttributes(typeof(T), false).SingleOrDefault();
if (attribute == null && isRequired)
{
throw new ArgumentException(
string.Format(
"The {0} attribute must be defined on member {1}",
typeof(T).Name,
member.Name));
}
return (T)attribute;
}
public static string DisplayName<T>(this T src,Expression<Func<T, object>> propertyExpression)
{
Type metadata = null;
var memberInfo = GetPropertyInformation(propertyExpression.Body);
if (memberInfo == null)
{
throw new ArgumentException(
"No property reference expression was found.",
"propertyExpression");
}
var attr = memberInfo.GetAttribute<DisplayNameAttribute>(false);
if (attr == null)
{
return memberInfo.Name;
}
return attr.DisplayName;
}
public static MemberInfo GetPropertyInformation(Expression propertyExpression)
{
MemberExpression memberExpr = propertyExpression as MemberExpression;
if (memberExpr == null)
{
UnaryExpression unaryExpr = propertyExpression as UnaryExpression;
if (unaryExpr != null && unaryExpr.NodeType == ExpressionType.Convert)
{
memberExpr = unaryExpr.Operand as MemberExpression;
}
}
if (memberExpr != null && memberExpr.Member.MemberType == MemberTypes.Property)
{
return memberExpr.Member;
}
return null;
}
}
Usage:
If you don't have LinqPAD, you should download it then you can test this pretty easily by just creating a new C# Program in LinkPAD
Debug.WriteLine(item.DisplayName(i => i.FName));
So it looks like you want to be able to decorate existing members of a partial class, by providing metadata in a separate partial piece. There's no built-in mechanism for that (see eg this question and the classes mentioned in the answer), but if you're willing to stick to a convention, you can roll your own:
So suppose we have
public partial class SpGetProfileInfoResult
{
public string FName { get; set; }
}
in a partial piece we can't change, and
public partial class SpGetProfileInfoResult
{
internal class Metadata
{
[System.ComponentModel.DisplayNameAttribute("[BILL-FNAME]")]
public string FName { get; set; }
}
}
in a partial piece we can change. You already have most of the pieces: in DisplayName(), you successfully determine that we are looking at the FName property; you then look for a DisplayNameAttribute on T.FName, but there isn't one, so that's where it stops.
What you need to do is, in the case where you don't find the attribute you need,
var attr = memberInfo.GetAttribute<DisplayNameAttribute>(false);
if (attr == null)
{
Look for a nested class named Metadata - note here is one place we use BindingFlags.NonPublic
// Try and get a nested metadata class
var metadataType = typeof(T)
.GetNestedType("Metadata",
BindingFlags.Public | BindingFlags.NonPublic);
If we find one:
if (metadataType != null)
{
Look for a member of the same name as was originally being talked about (BindingFlags.NonPublic again)
var membersOnMetadataType = metadataType.GetMember(memberInfo.Name,
BindingFlags.Instance |
BindingFlags.Public |
BindingFlags.NonPublic);
If there is one, use your helper method, but this time pass it the metadata type's member:
if (membersOnMetadataType.Any())
{
var attrOnMetadataType = membersOnMetadataType[0]
.GetAttribute<DisplayNameAttribute>(false);
return attrOnMetadataType.DisplayName;
(I've omitted a final nullity check here, as well as closing the control flow)
Depending on how distasteful you find that "Metadata" string, you could instead do something declarative with attributes:
have a class-level attribute that goes on SpGetProfileInfoResult (the piece you can change) that points at its Metadata using typeof (this is the approach taken by System.ComponentModel), or
have a class-level attribute that goes on Metadata, to have it claim 'I am a metadata type'. Then instead of searching for a nested class named a fixed string, we would instead search for a nested class having this particular attribute.
After working on this for a while I came up with a Hack. I am sure someone out there can help me clean this up a bit, but this is what I found works. I had to add the "Metadata" nested class to the DeclaringType and then do a GetMember on that result, which returns a collection of members.
public static string DisplayName<T>(this T src, Expression<Func<T, object>> propertyExpression)
{
var memberInfo = GetPropertyInformation(propertyExpression.Body);
var mytype = src.GetType();
string strType = mytype.Name + "+Metadata";
var metaType = Type.GetType(strType);
MemberInfo[] mem = metaType.GetMember(memberInfo.Name);
var att = mem[0].GetCustomAttributes(typeof(DisplayNameAttribute), true).FirstOrDefault() as DisplayNameAttribute;
if (att == null)
return memberInfo.Name;
else
return att.DisplayName;
}
I won't try to debug your code because you're using some classes that I'm not familiar with.
One thing I do know is that MemberInfo does not have a GetAttribute() function. You must be using an extension method there.
However I can tell you that you don't need any special bindingflags just because the type is internal. Only the visibility of the member is important, and in this case it's public.
using System;
using System.ComponentModel;
namespace ConsoleApplication1
{
internal class Metadata
{
[DisplayName("[BILL-FNAME]")]
public string FName { get; set; }
}
class Program
{
static void Main()
{
var memberInfo = typeof(Metadata).GetMember("FName")[0];
var atrributes = memberInfo.GetCustomAttributes(false);
Console.WriteLine(atrributes[0].GetType().Name);
}
}
}
Output:
DisplayNameAttribute

C# Using Reflection to Get a Generic Object's (and its Nested Objects) Properties

This is a scenario created to help understand what Im trying to achieve.
I am trying to create a method that returns the specified property of a generic object
e.g.
public object getValue<TModel>(TModel item, string propertyName) where TModel : class{
PropertyInfo p = typeof(TModel).GetProperty(propertyName);
return p.GetValue(item, null);
}
The code above works fine if you're looking for a property on the TModel item
e.g.
string customerName = getValue<Customer>(customer, "name");
However, if you want to find out what the customer's group's name is, it becomes a problem:
e.g.
string customerGroupName = getValue<Customer>(customer, "Group.name");
Hoping someone can give me some insight on this way out scenario - thanks.
Here's a simple method that uses recursion to solve your problem. It allows you to traverse an object graph by passing a "dotted" property name. It works with properties as well as fields.
static class PropertyInspector
{
public static object GetObjectProperty(object item,string property)
{
if (item == null)
return null;
int dotIdx = property.IndexOf('.');
if (dotIdx > 0)
{
object obj = GetObjectProperty(item,property.Substring(0,dotIdx));
return GetObjectProperty(obj,property.Substring(dotIdx+1));
}
PropertyInfo propInfo = null;
Type objectType = item.GetType();
while (propInfo == null && objectType != null)
{
propInfo = objectType.GetProperty(property,
BindingFlags.Public
| BindingFlags.Instance
| BindingFlags.DeclaredOnly);
objectType = objectType.BaseType;
}
if (propInfo != null)
return propInfo.GetValue(item, null);
FieldInfo fieldInfo = item.GetType().GetField(property,
BindingFlags.Public | BindingFlags.Instance);
if (fieldInfo != null)
return fieldInfo.GetValue(item);
return null;
}
}
Example:
class Person
{
public string Name { get; set; }
public City City { get; set; }
}
class City
{
public string Name { get; set; }
public string ZipCode { get; set; }
}
Person person = GetPerson(id);
Console.WriteLine("Person name = {0}",
PropertyInspector.GetObjectProperty(person,"Name"));
Console.WriteLine("Person city = {0}",
PropertyInspector.GetObjectProperty(person,"City.Name"));
In the System.Web.UI namespace there's a method to do that:
DataBinder.Eval(source, expression);
I'm guessing you just need to break this down into a couple of steps rather than trying to do it all in one, something like:
// First get the customer group Property...
CustomerGroup customerGroup = getValue<Customer>(customer, "Group");
// Then get the name of the group...
if(customerGroup != null)
{
string customerGroupName = getValue<CustomerGroup>(customerGroup, "name");
}
Since Group is the property of the customer, which itself hosts the property name, you have to go this way too.
But since '.' cant be part of the name of the property you can easyly use String.Substring to remove the first property name from string and call your method recursively.

How do I use reflection to get properties explicitly implementing an interface?

More specifically, if I have:
public class TempClass : TempInterface
{
int TempInterface.TempProperty
{
get;
set;
}
int TempInterface.TempProperty2
{
get;
set;
}
public int TempProperty
{
get;
set;
}
}
public interface TempInterface
{
int TempProperty
{
get;
set;
}
int TempProperty2
{
get;
set;
}
}
How do I use reflection to get all the propertyInfos for properties explicitly implementing TempInterface?
Thanks.
I think the class you are looking for is System.Reflection.InterfaceMapping.
Type ifaceType = typeof(TempInterface);
Type tempType = typeof(TempClass);
InterfaceMapping map = tempType.GetInterfaceMap(ifaceType);
for (int i = 0; i < map.InterfaceMethods.Length; i++)
{
MethodInfo ifaceMethod = map.InterfaceMethods[i];
MethodInfo targetMethod = map.TargetMethods[i];
Debug.WriteLine(String.Format("{0} maps to {1}", ifaceMethod, targetMethod));
}
The property getter and setter of an explicitly implemented interface property has an unusual attribute. It's IsFinal property is True, even when it is not a member of a sealed class. Try this code to verify my assertion:
foreach (AssemblyName name in Assembly.GetEntryAssembly().GetReferencedAssemblies()) {
Assembly asm = Assembly.Load(name);
foreach (Type t in asm.GetTypes()) {
if (t.IsAbstract) continue;
foreach (MethodInfo mi in t.GetMethods(BindingFlags.NonPublic | BindingFlags.Instance)) {
int dot = mi.Name.LastIndexOf('.');
string s = mi.Name.Substring(dot + 1);
if (!s.StartsWith("get_") && !s.StartsWith("set_")) continue;
if (mi.IsFinal)
Console.WriteLine(mi.Name);
}
}
}
Here's a modified solution based on the implementation given in this blog post:
var explicitProperties =
from prop in typeof(TempClass).GetProperties(
BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.DeclaredOnly)
let getAccessor = prop.GetGetMethod(true)
where getAccessor.IsFinal && getAccessor.IsPrivate
select prop;
foreach (var p in explicitProperties)
Console.WriteLine(p.Name);
Building on the answer by MrKurt:
var targetMethods =
from iface in typeof(TempClass).GetInterfaces()
from method in typeof(TempClass).GetInterfaceMap(iface).TargetMethods
select method;
var explicitProps =
from prop in typeof(TempClass).GetProperties(BindingFlags.Instance |
BindingFlags.NonPublic)
where targetMethods.Contains(prop.GetGetMethod(true)) ||
targetMethods.Contains(prop.GetSetMethod(true))
select prop;
I had to modify Jacob Carpenter's answer but it works nicely. nobugz's also works but Jacobs is more compact.
var explicitProperties =
from method in typeof(TempClass).GetMethods(BindingFlags.NonPublic | BindingFlags.Instance)
where method.IsFinal && method.IsPrivate
select method;
A simple helper class that could help:
public class InterfacesPropertiesMap
{
private readonly Dictionary<Type, PropertyInfo[]> map;
public InterfacesPropertiesMap(Type type)
{
this.Interfaces = type.GetInterfaces();
var properties = type.GetProperties(BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Public);
this.map = new Dictionary<Type, PropertyInfo[]>(this.Interfaces.Length);
foreach (var intr in this.Interfaces)
{
var interfaceMap = type.GetInterfaceMap(intr);
this.map.Add(intr, properties.Where(p => interfaceMap.TargetMethods
.Any(t => t == p.GetGetMethod(true) ||
t == p.GetSetMethod(true)))
.Distinct().ToArray());
}
}
public Type[] Interfaces { get; private set; }
public PropertyInfo[] this[Type interfaceType]
{
get { return this.map[interfaceType]; }
}
}
You'll get properties for each interface, even explicitly implemented.
It's overly complex. You have to reflect over the methods/properties of the Interface type, see if they exist in your class type, and compare them to see if they're the "same" when they do exist.
If something is in the interface but not the type you're testing, it's an explicit implementation. If it's in both, but different between the two, it's an explicit interface.
This seems a bit painful for no apparent reason!
My solution is for the case where you know the name of the property you are looking for and is pretty simple.
I have a class for making reflection a bit easier that I just had to add this case to:
public class PropertyInfoWrapper
{
private readonly object _parent;
private readonly PropertyInfo _property;
public PropertyInfoWrapper(object parent, string propertyToChange)
{
var type = parent.GetType();
var privateProperties= type.GetProperties(BindingFlags.NonPublic | BindingFlags.Instance);
var property = type.GetProperty(propertyToChange) ??
privateProperties.FirstOrDefault(p => UnQualifiedNameFor(p) == propertyName);
if (property == null)
throw new Exception(string.Format("cant find property |{0}|", propertyToChange));
_parent = parent;
_property = property;
}
private static string UnQualifiedNameFor(PropertyInfo p)
{
return p.Name.Split('.').Last();
}
public object Value
{
get { return _property.GetValue(_parent, null); }
set { _property.SetValue(_parent, value, null); }
}
}
You cant just do == on name because explicitly implemented properties have fully qualified names.
GetProperties needs both the search flags to get at private properties.
Jacob's code is missing a filter:
var props = typeof(TempClass).GetInterfaces().Where(i => i.Name=="TempInterface").SelectMany(i => i.GetProperties());
foreach (var prop in props)
Console.WriteLine(prop);

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