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GeneralRe: MakeGenericType/CreateInstance Object to underlying Type at run-time: why this works is driving me crazy Pin
BillWoodruff28-Sep-21 9:47
mveBillWoodruff28-Sep-21 9:47 
AnswerRe: MakeGenericType/CreateInstance Object to underlying Type at run-time: why this works is driving me crazy Pin
OriginalGriff28-Sep-21 6:30
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GeneralRe: MakeGenericType/CreateInstance Object to underlying Type at run-time: why this works is driving me crazy Pin
BillWoodruff28-Sep-21 10:19
mveBillWoodruff28-Sep-21 10:19 
GeneralRe: MakeGenericType/CreateInstance Object to underlying Type at run-time: why this works is driving me crazy Pin
OriginalGriff28-Sep-21 10:40
mveOriginalGriff28-Sep-21 10:40 
GeneralRe: MakeGenericType/CreateInstance Object to underlying Type at run-time: why this works is driving me crazy Pin
BillWoodruff29-Sep-21 0:57
mveBillWoodruff29-Sep-21 0:57 
Questionled matrix display Pin
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QuestionC# 8 nullable reference question / conundrum Pin
Super Lloyd25-Sep-21 1:36
MemberSuper Lloyd25-Sep-21 1:36 
I have my own custom list class in my utility library (provide some additional benefits like having buildin readonly view or being observable or being undoable)

and I am just migrating to .NET5 and pondering the nullable reference implication.
my type is like so:
C#
public class DocumentList<T> : IList<T>, IList
{
    //.....
}

but what of that method
C#
object? System.Collections.IList.this[int index]
{
    get { return this[index]; }
    set { this[index] = (T)value; }
}

value could be null, so .. perhaps I should throw an exception if value is null?
But what if one make a DocumentList<T?> then I expect the values to be null and should not throw an exception...

EDIT2 In fact.. that MSDN snippet below.. doesn't properly test that! Blush | :O :/

EDIT answering my own question, thanks to MSDN reference source Reference Source
C#
// Allow nulls for reference types and Nullable<U>, but not for value types.
internal static void IfNullAndNullsAreIllegalThenThrow<T>(object value, ExceptionArgument argName) 
{
    //Note that default(T) is not equal to null for value types except when T is Nullable<U>. 
    if (value == null && !(default(T) == null))
        ThrowHelper.ThrowArgumentNullException(argName);
}
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modified 25-Sep-21 12:45pm.

QuestionConvering time representation format Pin
Alex Dunlop21-Sep-21 23:26
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QuestionHow to convert Persian date representation? Pin
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GeneralRe: How to convert Persian date representation? Pin
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