How to get Fully Qualified Name of a Type using Reflection in C#

Question

I have a scenario where I need to check whether a DataContext of a control is implementing "INotifyPropertyChanged" and another interface called "ITObject". The interface "ITObject" is located in some other assembly and the implementing class is called "TObjectBase" which has an event called "TObjectChanged".

We do not add their assemblies to our project but instead they will be adding our assemblies to their projects which we build and give them.

The problem I have is that the only information I have is the textual representation of these class/interface names and nothing more but I need to check at runtime whether the DataContext of the control is implementing these interfaces and hook to the TObjectChanged event and react to it.

I tried using Type.GetType("TObjectBase") to check it, but I require the fully qualified name, isn't it? because they are all located in a different assembly that I don't have any idea of. Also, IsAssignableFrom("ITObject") also fails.

I was wondering if the userbase here could help me with this.

possible duplicate of [How to determine if a type implements an interface with C# reflection](http://stackoverflow.com/questions/4963160/how-to-determine-if-a-type-implements-an-interface-with-c-sharp-reflection) — w.b, Dec 25 '13 at 02:51

Travis · Accepted Answer · 2013-12-26T01:43:52.157

You can load all the active assemblies in the app domain, then walk each assembly's types looking for a name match. Without the assembly name though, you can't use Type.GetType() as you saw.

The following simple program works for me.

class Program
{
    static void Main(string[] args)
    {
        Console.WriteLine(GetFqTypeName("IMyInterface"));
        Console.ReadKey();
    }

    static String GetFqTypeName(string shortTypeName)
    {
        return AppDomain.CurrentDomain.GetAssemblies()
            .ToList()
            .SelectMany(x => x.GetTypes())
            .Where(x => x.Name == shortTypeName)
            .Select(x => x.FullName)
            .FirstOrDefault();
    }
}

public interface IMyInterface { }

score 1 · Answer 2 · answered Dec 25 '13 at 02:47

1

Try the is operator.

if (DataContext is INotifyPropertyChanged && DataContext is ITObject)
{
   // magic
}

You also have IsAssignableFrom backwards.

typeof(ITObject).IsAssignableFrom(DataContext.GetType());

answered Dec 25 '13 at 02:47

Daniel A. White

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That doesn't really workout. I don't have a reference to it and the only thing I know about its name is the textual representation. `code if(currentDataContext is Type.GetType("ITObject")) { // Functionality } ` doesn't work either ... – Harsha Dec 25 '13 at 02:50
I thought you said you had a reference to the type `ITObject`? – Daniel A. White Dec 25 '13 at 02:52
No, I do not have the reference of the ITObject as we do not add their assemblies to our projects. Please see my below post on how I am trying to achieve it :) PS: I am unable to post code in my comments, so I posted as a separate reply instead – Harsha Dec 25 '13 at 04:23

How to get Fully Qualified Name of a Type using Reflection in C#

2 Answers2