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how to get all the properties and values from the generic parameter

I want to compare all of my list of generic T property value to my local variable searchText.
i already try:
x.GetType().GetProperties().All(props => props.GetValue(x).ToString().ToLower().Contains(searchText.ToLower()))
and i get error : NullReferenceException: Object reference not set to an instance of an object.
here my full method :
protected List<T> ProcessCollection<T>(List<T> lstElements, IFormCollection requestFormData, Func<T, IComparable> getProp)
{
string searchText = string.Empty;
Microsoft.Extensions.Primitives.StringValues tempOrder = new[] { "" };
if (requestFormData.TryGetValue("search[value]", out tempOrder))
{
searchText = requestFormData["search[value]"].ToString();
}
var skip = Convert.ToInt32(requestFormData["start"].ToString());
var pageSize = Convert.ToInt32(requestFormData["length"].ToString());
if (requestFormData.TryGetValue("order[0][column]", out tempOrder))
{
var columnIndex = requestFormData["order[0][column]"].ToString();
var sortDirection = requestFormData["order[0][dir]"].ToString();
tempOrder = new[] { "" };
if (requestFormData.TryGetValue($"columns[{columnIndex}][data]", out tempOrder))
{
var columName = requestFormData[$"columns[{columnIndex}][data]"].ToString();
if (pageSize > 0)
{
var prop = GetProperty<T>(columName);
if (sortDirection == "asc")
{
return lstElements.Where(x=>x.GetType().GetProperties().All(props => props.GetValue(x).ToString().ToLower().Contains(searchText.ToLower()))
.Skip(skip).Take(pageSize).OrderBy(b => prop.GetValue(b)).ToList();
}
else
return lstElements
.Where(x => getProp(x).ToString().ToLower().Contains(searchText.ToLower()))
.Skip(skip).Take(pageSize).OrderByDescending(b => prop.GetValue(b)).ToList();
}
else
return lstElements;
}
}
return null;
}
this is how i call my method :
var listItem = ProcessCollection<Jtabel>(temp,requestFormData,x=>x.Name);
the temp that i pass to method already filled
and this is the class type that i pass to this method
public class Jtabel : BaseModel
{
public string Creator { get; set; }
public string Name { get; set; }
public int SO { get; set; }
public int SOD { get; set; }
public int SAP { get; set; }
public int BA { get; set; }
public int Invoice { get; set; }
public int EPD { get; set; }
public double DP { get; set; }
}
i will try to explain more detail as much i can, so i want to get all of my property from Jtabel class to my ProcessCollection where inside the method all of Jtable property will test each element that's contain searchText.

Foreach() with if statements not affecting variables

I am trying to add an InventoryState to the various products extended from my IProduct interface I created before, but the foreach() statement I made to check the state of the inventory is not changing the default value of Unassigned on the property...
This is the properties for each product object:
public string ProductType
{
get { return "Apple"; }
set { }
}
public double BulkPrice
{
get { return 0.99; }
set { }
}
public double RetailPrice
{
get { return 1.49; }
set { }
}
public int Quantity
{
get { return 50; }
set { }
}
public int MaxQuantity
{
get { return 100; }
set { }
}
public InventoryState Status
{
get { return InventoryState.Unassigned; }
set { }
}
And these are the various declarations and the foreach in question:
public enum InventoryState
{
Full,
Selling,
Stocking,
Empty,
Unassigned
}
public interface IProduct
{
string ProductType { get; set; }
double BulkPrice { get; set; }
double RetailPrice { get; set; }
int Quantity { get; set; }
int MaxQuantity { get; set; }
InventoryState Status { get; set; }
}
public static IProduct[] ProductList =
{
new Apple(),
new Blueberry()
};
foreach (IProduct productName in ProductList) // broken- not being called :(?
{
if (productName.Quantity == productName.MaxQuantity)
{
productName.Status = InventoryState.Full;
return productName.Status;
}
else if (productName.Quantity <= (productName.MaxQuantity * (0.5)))
{
productName.Status = InventoryState.Stocking;
}
else if (productName.Quantity == 0)
{
productName.Status = InventoryState.Empty;
}
else
{
productName.Status = InventoryState.Selling;
}
}

You always do in your automatic properties
get { return "some value";}
Even if you assign a value to it, it will always return "some value" even if the underlying value is different.
Do this for all your properties:
public string ProductType
{
get; set;
} = "Apple";
They will have default value "Apple" but it will get assigned and returned correctly.
Note that auto property default value is only from C# 6.0 onward.
Otherwise you need a private backing field.

C# Accessing custom attribute of owner object

How can I access the custom attribute of the parent or owner object.
Look at the FieldInfo property of the SQLFieldInfo struct
Here's a more detailed program that will compile and run that shows what I need.
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
Employee myclass = new Employee();
// Load from sql server...
myclass.Name = "Alain";
myclass.Age = 51;
//----
MessageBox.Show(myclass.Name.ToString()); // Should return Alain
MessageBox.Show(myclass.Age.FieldInfo.Type.ToString()); // Should output "int"
}
}
// This next class is generated by a helper exe that reads SQL table design and create the class from it
[SQLTableAttribute(DatabaseName = "Employees", Schema = "dbo", TableName = "Employees")]
public class Employee
{
[SQLFieldAttribute(FieldName = "ID", Type = SqlDbType.Int)]
public SQLFieldInfo<int> ID { get; set; }
[SQLFieldAttribute(FieldName = "Name", Type = SqlDbType.NVarChar, Size = 200)]
public SQLFieldInfo<String> Name { get; set; }
[SQLFieldAttribute(FieldName = "Age", Type = SqlDbType.Int)]
public SQLFieldInfo<int> Age { get; set; }
}
public struct SQLFieldInfo<T>
{
private readonly T value;
public SQLFieldInfo(T Value)
{
this.value = Value;
}
public static implicit operator SQLFieldInfo<T>(T Value)
{
return new SQLFieldInfo<T>(Value);
}
public T Value
{
get
{
return this.value;
}
}
public override string ToString()
{
return this.value.ToString();
}
public SQLFieldAttribute FieldInfo
{
get
{
// Need to retreive the attribute class of the parent or declaring member
return null;
}
}
}
// Holds the sql field information
public class SQLFieldAttribute : Attribute
{
public string FieldName { get; set; }
public SqlDbType Type { get; set; }
public bool AllowNull { get; set; }
public int Size { get; set; }
}
// Holds the sql table information
public class SQLTableAttribute : Attribute
{
public string DatabaseName { get; set; }
public string Schema { get; set; } = "dbo";
public string TableName { get; set; }
}
Thank you!
Alain

My data class is as follows (should be fairly translatable to A above):
public class Foo
{
[Argument(Help = "Name", AssignmentDelimiter = "=")]
public string Name
{
get;
set;
}
}
A helper class is responsible of reading attribute values of objects:
static public string GetCommandLineDelimiter<T>(Expression<Func<T>> property)
{
if(property != null)
{
var memberExpression = (MemberExpression)property.Body;
string propertyName = memberExpression.Member.Name;
PropertyInfo prop = typeof(Arguments).GetProperty(propertyName);
if(prop != null)
{
object[] dbFieldAtts = prop.GetCustomAttributes(typeof(ArgumentAttribute), true);
if(dbFieldAtts.Length > 0)
{
return ((ArgumentAttribute)dbFieldAtts[0]).AssignmentDelimiter;
}
}
}
return null;
}
To use it, simply:
string delimiter = GetCommandLineDelimiter(() => myObject.Name);
That will get the attribute value of AssignmentDelimiter on property Name, i.e. "=".

First, MSDN is your friend.
Then, if you want to get the attributes for ancestors just specify true in the inherit flag of the method:
var attribute = typeof(A).GetProperty("myprop").GetCustomAttributes(true)
.OfType<MycustomAttrib>().FirstOrDefault();

This works. I am doing a lazy initialization of a reference to the custom attribute by using reflection to look at all the properties of all the types.
public class MycustomAttribAttribute : Attribute
{
public MycustomAttribAttribute(string name)
{
this.Name=name;
}
public string Name { get; private set; }
}
class A
{
public A() { MyProp=new B(); }
[MycustomAttrib(name: "OK")]
public B MyProp { get; set; }
}
class B
{
private static Lazy<MycustomAttribAttribute> att = new Lazy<MycustomAttribAttribute>(() =>
{
var types = System.Reflection.Assembly.GetExecutingAssembly().DefinedTypes;
foreach(var item in types)
{
foreach(var prop in item.DeclaredProperties)
{
var attr = prop.GetCustomAttributes(typeof(MycustomAttribAttribute), false);
if(attr.Length>0)
{
return attr[0] as MycustomAttribAttribute;
}
}
}
return null;
});
public string MyProp2
{
get
{
return att.Value.Name;
}
}
}
class Program
{
static void Main(string[] args)
{
// Finds the attribute reference and returns "OK"
string name = (new A()).MyProp.MyProp2;
// Uses the stored attribute reference to return "OK"
string name2 = (new A()).MyProp.MyProp2;
}
}

C# validate model by mapping values of multiple Lists

I need to run validation on JSON input model by taking the value from one List and check if it exists in another. This value is a rating is from 1 - 5. If there is no matching number, then it should throw an error. Below is the code and this logic goes in the section commented with : //check if rating exist in score table
namespace Alpha.Model
{
// INPUT
public class AlphaCalcParamMethod
{
public ICollection<PortfolioInputModel> portfolios { get; set; }
public Setting settings { get; set; }
public bool Validation(ref string errString)
{
// Check if portfolio exists
if(portfolios == null || portfolios.Count < 1)
{
errString = "At least 1 Portfolio.";
return false;
}
//check if weight adds upto 1
foreach(var portfolio in portfolios)
{
// var holdings = new List<PortfolioHoldingInput>();
var weightAggregator = 0.00;
foreach(var holding in portfolio.portfolioHoldings)
{
weightAggregator += holding.fundWeight;
}
if (weightAggregator != 1)
{
errString = "Fund Weights should add upto 1";
}
return false;
}
//check if rating exist in score table
foreach(var portfolio in portfolios)
{
var holdings = new List<PortfolioHoldingInput>();
var scores = new List<Setting>();
foreach(var holding in holdings)
{
//fetch the value of fundRating double
foreach(var score in scores)
{
//check if the value above exist in grossAlpha's List fundRating
// if it doesn't return false
}
}
return false;
}
return true;
}
}
// OUTPUT
public class AlphaCalcResultMethod
{
public List<PortfolioOutputModel> portfolios { get; set; }
}
public class PortfolioInputModel
{
public string portfolioIdentifier { get; set; }
public ICollection<PortfolioHoldingInput> portfolioHoldings { get; set; }
}
public class PortfolioOutputModel
{
public string portfolioIdentifier { get; set; }
public double portfolioAlpha { get; set; }
public ICollection<PortfolioHoldingOutput> portfolioHoldings { get; set; }
}
public class PortfolioHoldingInput
{
public string fundIdentifier { get; set; }
public int fundRating { get; set; }
public double fundExpenseRatio { get; set; }
public double fundWeight { get; set; }
}
public class PortfolioHoldingOutput
{
public string fundIdentifier { get; set; }
public int fundRating { get; set; }
public double fundExpenseRatio { get; set; }
public double fundWeight { get; set; }
public double fundAlpha { get; set; }
}
public class Setting
{
public List<GrossAlpha> grossAlphas { get; set; }
}
public class GrossAlpha
{
public int fundRating { get; set; }
public double grossAlpha { get; set; }
}
}

If you are going to return additional values from method, you should use out parameters.
Don't specify type of variable in variable name. I.e. instead of errorString just use error. Hungarian notation and other tricks are not needed with modern IDEs.
Double type is not precise. You should avoid comparing it to integer values for equality. Prefer greater or less than comparisons.
Use LINQ to replace loops
Method name Validation is a noun. That is pretty confusing for method which is action and should a verb. Consider rename it to Validate or IsValid
Code
public bool IsValid(out string error)
{
if (portfolios?.Any() == false)
{
error = "At least 1 Portfolio.";
return false;
}
if (portfolios.Any(p => p.portfolioHoldings.Sum(h => h.fundWeight) < 1))
{
error = "Fund Weights should add upto 1";
return false;
}
var holdings = portfolios.SelectMany(p => p.portfolioHoldings);
var validRatings = new List<int> { 1, 2, 3, 4, 5 };
if (holdings.Any(h => !validRatings.Contains(h.fundRating)))
{
error = "Fund ratings should be in " + String.Join(",", validRatings);
return false;
}
error = "";
return true;
}
Note: if valid ratings are sequential numbers, then you can just check range of fundRating value:
if (holdings.Any(h => h.fundRating < 1 || 5 < h.fundRating))

Look this code:
if(!score.grossAlphas.Exists(x => x.fundRating == holding.fundRating))
{
return false;
}
it check if exists grossAlphas with fundRating equals holding.fundRating.
put it in the loop where you want to check, let me know if it is what you want and if it works.

Parsing JSON into Object

Trying to get the result from a webservice call to return a Model. I eep getting the error:
Cannot deserialize the current JSON array (e.g. [1,2,3]) into type 'CI.Models.Schedule' because the type requires a JSON object (e.g. {"name":"value"}) to deserialize correctly.
public Schedule getCourseSchedule()
{
var obj = new
{
States = new[] { new { State = "MX" } },
Zip = "",
Miles = "",
PaginationStart = 1,
PaginationLimit = 3
};
using (var client = new WebClient())
{
client.Headers[HttpRequestHeader.ContentType] = "apoplication/json";
var url = "http://192.168.1.198:15014/ShoppingCart2/CourseSchedule";
var json = JsonConvert.SerializeObject(obj);
byte[] data = Encoding.UTF8.GetBytes(json);
byte[] result = client.UploadData(url, data);
string returnjson = Encoding.UTF8.GetString(result);
Schedule sched = JsonConvert.DeserializeObject<Schedule>(returnjson);
return sched;
}
}
Schedule Model:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Globalization;
namespace CI.Models
{
public class Schedule
{
public IEnumerable<Course> Courses { get; set; }
}
public class Course
{
/*
JSON Data returned from web service:
{
"ProgramGroup":"MR",
"ProgramCode":"RM",
"EventCode":"20160901MXMR",
"FormalDate":"September 1-2, 2016",
"StartDate":"2016\/09\/01",
"Price":5,
"LocName":"WB Hotel",
"LocAddress":"Av. Speedy Gonzales 220",
"LocCity":"Monterrey",
"LocState":"MX",
"LocZipCode":null,
"LicenseeURL":null,
"AgendaURL":"NA",
"SeatsAreAvailable":"2",
"GeneralInfoHTML":"General Info goes here.",
"GateKeeperHTML":null,
"EventType":"SS",
"TotalCourses":3
}
*/
public string ProgramGroup { get; set; }
public string ProgramCode { get; set; }
public string EventCode { get; set; }
public string FormalDate { get { return FormalDate; } set { FormalDate = convertFormalDateToSpanish(value); } }
public string StartDate { get; set; }
public double Price { get; set; }
public string LocName { get; set; }
public string LocAddress { get; set; }
public string LocCity { get ; set; }
public string LocState { get; set; }
public string LocZipCode { get; set; }
public string LicenseeURL { get; set; }
public string AgendaURL { get { return AgendaURL; } set { AgendaURL = buildAgendaLink(value); } }
public string SeatsAreAvailable { get; set; }
public string GeneralInfoHTML { get; set; }
public string GateKeeperHTML { get; set; }
public string EventType { get; set; }
public int TotalCourses { get; set; }
public string convertFormalDateToSpanish(string val)
{
DateTime TheDate = DateTime.Parse(StartDate);
string[] FormalDate = val.Split(" ".ToCharArray());
CultureInfo ci = new CultureInfo("es-ES");
string _Date = FormalDate[1].Replace("-", " al ").Replace(",", "");
string _Month = ci.TextInfo.ToTitleCase(TheDate.ToString("MMMM", ci));
val = string.Concat(_Date, " ", _Month);
return val;
}
private string buildAgendaLink(string val)
{
if (val.Trim() != "")
{
val = string.Concat("Agenda");
}
else
{
val = "Agenda";
}
return val;
}
}
}

Your server returns an array. Just try
Course[] courses = JsonConvert.DeserializeObject<Course[]>(returnjson);

Note that this is not an answer to your original problem, but I added it like an answer in order to explain my comment above with some actual code.
First problem with your code is that FormalDate and AgendaUrl properties simply won't work. Accessing them will result in a StackOverflowException, because you basically defined them recursively.
A property is merely syntax sugar for two separate getter/setter methods, so by writing this:
public class Course
{
public string FormalDate
{
get { return FormalDate; }
}
}
You are basically writing this:
public class Course
{
public string GetFormalDate()
{
// recursive call, with no terminating condition,
// will infinitely call itself until there is no
// more stack to store context data (and CLR
// will then throw an exception)
return GetFormalDate();
}
}
To fix that, you need to add an actual backing field, e.g.:
public class Course
{
private string _formalDate; // <-- this is a backing field;
// and this property uses the backing field to read/store data
public string FormalDate
{
get { return _formalDate; }
set { _formalDate = convertFormalDateToSpanish(value); }
}
}
Additionally, it's unusual for a property getter to return a different value than the one set through a setter. In other words, I would never expect this from a class:
var course = new Course();
course.StartDate = "2016/09/01";
course.FormalDate = "September 1-2, 2016";
Console.WriteLine(course.FormalDate); // prints "1 al 2 Septiembre" ?
I would rather move this functionality into a different class, or at least create different properties which return these values:
public class CourseInfo
{
// this is now a "dumb" auto-implemented property
// (no need for a backing field anymore)
public string FormalDate { get; set; }
// this read-only property returns the converted value
public string LocalizedFormalDate
{
get
{
return convertFormalDateToSpanish(FormalDate);
}
}
}