Why does it return null when I try to invoke generic methods?

Question

I've been trying to execute generic methods and using recursion. The problem is that the method GetMethod returns null. How can I improve the code?

public static T GetElementObject<T>(this XElement element)
{
    T returnObject = Activator.CreateInstance<T>();
    PropertyInfo[] propertyInfos = returnObject.GetType().GetProperties();
    Type propertyType;

    foreach (PropertyInfo propertyInfo in propertyInfos)
    {
        propertyType = propertyInfo.PropertyType;

        if (propertyType.IsAssignableFrom(typeof(BaseProxyEntity)))
        {
            MethodInfo getElementObject = typeof(Utility).GetMethod("GetElementObject<>", System.Reflection.BindingFlags.Static | BindingFlags.Public).MakeGenericMethod(propertyType);
            propertyInfo.SetValue(returnObject, getElementObject.Invoke(null, new object[] { element.Descendants(propertyInfo.Name) }), null);
        }
        else if (propertyType.IsValueType == true)
        {
            MethodInfo CastValue = typeof(Utility).GetMethod("CastValue<>", System.Reflection.BindingFlags.Static | BindingFlags.Public).MakeGenericMethod(propertyType);
            propertyInfo.SetValue(returnObject, CastValue.Invoke(null, new object[] { element.Attribute(propertyInfo.Name).Value }), null);
        }
        //Other else conditions ...
    }

    return returnObject;
}

Possibly helpful link : http://msdn.microsoft.com/en-us/library/ms172334.aspx — Mikeb, Dec 29 '11 at 14:03
Are your binding flags correct? Could you show the code for the Utility class? — Wouter de Kort, Dec 29 '11 at 14:04
There's nothing special in Utility class. It just has some static methods like the one shown above. You can see the method definition for "GetElementObject" which is called recursively. — wasimbhalli, Dec 29 '11 at 14:19
possible duplicate: http://stackoverflow.com/questions/4035719/getmethod-for-generic-method — phoog, Dec 29 '11 at 14:46

score 1 · Answer 1 · answered Dec 29 '11 at 14:04

1

GetMethod("GetElementObject<>", ...)

Will allways return null, as there is no such method. Names are mangled for generic types, start with listing all methods and proceed from there.

answered Dec 29 '11 at 14:04

Eugen Rieck

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score 1 · Accepted Answer · answered Dec 29 '11 at 14:43

1

While Eugen Rieck is correct that names are mangled for generic types, they are not mangled for generic methods. Try without the angle brackets: GetMethod("GetElementObject", ... and GetMethod("CastValue",

answered Dec 29 '11 at 14:43

phoog

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Why does it return null when I try to invoke generic methods?

2 Answers2

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