Visual Basic

Option Explicit On
Option Strict On

Imports System.Reflection

Module Module1

    Public Class ChildClass
    End Class

    Public Class SomeClass
        Public Property Children As ICollection(Of ChildClass) = New HashSet(Of ChildClass)
    End Class

    Sub Main()
        Dim tempType = GetType(ChildClass)
        Dim someClass = New SomeClass
        someClass.Children.Add(New ChildClass)

        Dim customList As Type = GetType(List(Of )).MakeGenericType(tempType)
        Dim objectList As IList = CType(Activator.CreateInstance(customList), IList)

        ' Copy items from a PropertyInfo list to the object just created
        Dim o As Object = someClass
        Dim p As PropertyInfo = o.[GetType]().GetProperty("Children")
        Dim copyFrom As IEnumerable = CType(p.GetValue(o, Nothing), IEnumerable)
        For Each item As Object In copyFrom
            objectList.Add(item)
        Next
        ' Will throw exceptions if the types don't match.
        ' Iterate and access the items of "objectList"
        ' (objectList declared above as non-generic IEnumerable)
        For Each item As Object In objectList
            Debug.WriteLine(item.ToString())
        Next
    End Sub

End Module

Error  103 Too few type arguments to 'System.Collections.Generic.IList(Of T)'

Imports System.Collections
Imports System.Collections.Generic

Imports System.Collections

1. I want first to initialize an empty list.
   Because if I have just the :
   

   dim itemlist as Ilist

Dim customList As Type = GetType(List(Of )).MakeGenericType(GetType(MyClass))
        itemlist = CType(Activator.CreateInstance(customList), IList)

If itemlist.Count > 0 Then

• The list is not yet created . ( So it's just declared as mylist as Ilist).
• The list is created ( with your code ) but the items are deleted ( or has no items ).

If mylist IsNot Nothing AndAlso mylist.Count > 0 Then
End If

CType(CallByName(MyObject, "Child1", CallType.Get), HashSet(Of Child1)).ElementAt(k)

Enumerable.ElementAt(CallByName(MyObject, "Child1", CallType.Get), k)

Dim element = Enumerable.ElementAt(CallByName(MyObject, "Child1", CallType.Get), k)

Public Function CopyEntity(Of T As {Class, New})(ctx As MyEntities, entity As T, Optional copyKeys As Boolean = False) As T
       Dim clone As New T()
       Dim en = ctx.Entry(clone)
       en.State = System.Data.Entity.EntityState.Added
       ctx.Entry(clone).CurrentValues.SetValues(entity)
       en.State = System.Data.Entity.EntityState.Detached
       Return clone
   End Function

fhitm = CopyEntity(context, element,False)

An unhandled exception of type 'System.InvalidOperationException' occurred in EntityFramework.dll

Additional information: The entity type Object is not part of the model for the current context.

CTypeDynamic(Element,System.Type.Gettype("Child1"))

System.Type.Gettype("Child1")

Dim element = Enumerable.ElementAt(CallByName(MyObject, "Child1", CallType.Get), k)
REM "element" actually is of the type the elements of Child1 have
REM but at this point it's treated as type Object

REM so this generic function is called for the generic type Object
Public Function CopyEntity(Of T As {Class, New})(ctx As MyEntities, entity As T, ...) As T
    REM so "clone" actually is created as just an Object and not of the same type as "element" / "entity"
    Dim clone As New T()
    REM and the type Object of course isn't a valid entity-type in your context
    Dim en = ctx.Entry(clone)

// CEClass    : class that contains the function CopyEntity
// CEInstance : an instance of CEClass

MethodInfo mi = typeof(CEClass).GetMethod("CopyEntity");
mi = mi.MakeGenericMethod(typeof(MyEntities), element.GetType(), typeof(bool));
// you could cache "mi"

object clone = mi.Invoke(CEInstance, new object[] {context, element, false});

"REM so "clone" actually is created as just an Object and not of the same type as "element" / "entity"

Ctype(element,Child1)

System.Type.Gettype("Child1")

dilkonika wrote:

This is not true because I try to use this instruction :
--- and after that everything works correctly

dilkonika wrote:

the type specified as parameter inside CtypeDynamic

dilkonika wrote:

But where can I find the namespace for my entity object ?