Question

I have a extension method as below.

 public static class ExtensionMethod
{
    public static string GetTableName<T>(this ObjectContext context) where T : class
    {
        //Content
    }
}

And I invoke this method as below.

static void Main(string[] args)
    {
        using (BreakAwayEntities context = new BreakAwayEntities())
        {
            Customer cus = context.Customers.First();

            ObjectStateEntry entry = context.ObjectStateManager.GetObjectStateEntry(cus);
            Type t = entry.Entity.GetType();               
            MethodInfo method = typeof(ExtensionMethod).GetMethod("GetTableName");
            MethodInfo genericMethod = method.MakeGenericMethod(t);
            genericMethod.Invoke(null, null);         
        }
    }    

But at the last line of the code “genericMethod.Invoke(null,null)” throws an exception “Parameter count mismatch.”
Anyone can help?

Answer 1

The GetTableName method has one parameter but you are calling Invoke will a second argument of null indicating that no parameters should be passed. You need to pass your ObjectContext as the second parameter:

genericMethod.Invoke(null, new object[] { context });