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I am trying to call a generic function where the type of the generic function is determined by an input string. I want a function that takes in a string, uses reflection to turn that string into a type and then calls a generic function with that type. I have been working with the solution proposed in How do I use reflection to call a generic method? but I just cannot get it to work. Any help would be greatly appreciated.

//This is the generic function(just a simple example function that writes out the incoming type):
public class SelectableRepository
{
    public virtual string GetTypeOfEntity<TEntity>()
    {
        return typeof(TEntity).ToString();
    }
}

//This is the controller that is attempting to call the generic function with the type of "inputString"
public class MyController
{
    public void MyFunction(string inputString)
    {
        //This is how I have been trying to invoke the method but to no avail:
        var myType = Type.GetType("Models.DatabaseModels." + inputString);              //Get the type of the input string
        MethodInfo method = typeof(SelectableRepository).GetMethod("GetTypeOfEntity");  //Get the generic method from SelectableRepository
        MethodInfo genericMethod = method.MakeGenericMethod(myType);                    //Initialize the generic method with the type from the input string
        genericMethod.Invoke(this, null);                                               //Call the method, I'm pretty sure this is wrong
    }
}

//This is an example of a class that could go into the generic method, the inputString would then be "Company"
namespace Models.DatabaseModels
public class Company 
{
    public string Name { get; set; }
}

I put a breakpoint on the genericMethod.Invoke line and looked at the contents of my variables:

myType = {Models.DatabaseModels.Company}
method = {System.String GetTypeOfEntity[TEntity]()}
genericMethod = {System.String GetTypeOfEntity[Company]()}

I am getting an error on the last line of this code: genericMethod.Invoke(this, null);

The error reads: TargetException: Object does not match target type.

Am I doing something completely wrong?

Fridrik
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    You need an instance of `SelectableRepository` on which to call the method. That object should be the first argument you pass to `genericMethod.Invoke()`. E.g. `genericMethod.Invoke(new SelectableRepository(), null);` but I'm guessing you have an instance already laying around somewhere. – itsme86 Jun 20 '18 at 15:16
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    Your `this` looks funky in the `genericMethod.Invoke(this, null);`. This is saying that you want to invoke the method on `this` which in your context is the MyController object... – Chris Jun 20 '18 at 15:19
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    Thank you itsme86! I did have an instance of SelectableRepository laying around and by changing the last line of the code to: genericMethod.Invoke(selectableRepository , null); it now works as expected. Thank you so much :) – Fridrik Jun 20 '18 at 15:50

0 Answers0