I am loading an assembly and calling a static method that will create a new object of type “MyClass1” (this type is specified at runtime) through reflection using MethodInfo.Invoke(). This works fine when the method is a normal sync method. However, the method being called is an async method which returns Task<MyClass1>, which will be used to retrieve the result using task.Result.
Ideally I should be using MyClass1 as TResult in the task, but the type is determined only at runtime so I can't do that. I am looking for a way to get the task and the result. I am trying to cast the TResult to System.Object and get the class as a generic Object. The following is the code I am using for this purpose.
public static void LoadAssembly()
{
// Calling static async method directly works fine
Task<MyClass1> task1 = MyClass1.MakeMyClass1();
MyClass1 myClass1 = task1.Result;
// Calling static async method through reflection through exception.
Assembly assembly = Assembly.LoadFrom(dllName);
Type type = assembly.GetType("AsyncDll.MyClass1");
var types = assembly.GetTypes();
MethodInfo[] methodInfos = types[0].GetMethods(BindingFlags.Public | BindingFlags.Static);
Type myClassType = types[0];
MethodInfo mi = myClassType.GetMethod("MakeMyClass1");
Object obj = Activator.CreateInstance(mi.ReflectedType);
Task<Object> task = (Task<Object>)mi.Invoke(obj, null); // Exception occurs here.
Object result = task.Result;
}
Following is the method (test code) being called through reflection. This
public class MyClass1
{
public static async Task<MyClass1> MakeMyClass1()
{
MyClass1 newObject = null;
await Task.Run(() =>
{
newObject = new MyClass1();
});
return newObject;
}
...
}
Unfortunately, the casting of TResult is causing System.InvalidCastException.
An unhandled exception of type 'System.InvalidCastException' occurred in Test.exe
Additional information: Unable to cast object of type 'System.Threading.Tasks.Task`1[MyClass1]' to type 'System.Threading.Tasks.Task`1[System.Object]'.
How can I cast the TResult in Task<> to a generic object and get the result using task.Result? I would appreciate any help resolving this issue.
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