MethodBase.Invoke Method (Object, array<Object[])

Parameters

• obj
  Type: System.Object
  The object on which to invoke the method or constructor. If a method is static, this argument is ignored. If a constructor is static, this argument must be nulla null reference (Nothing in Visual Basic) or an instance of the class that defines the constructor.

• parameters
  Type: array<System.Object[]
  An argument list for the invoked method or constructor. This is an array of objects with the same number, order, and type as the parameters of the method or constructor to be invoked. If there are no parameters, parameters should be nulla null reference (Nothing in Visual Basic).
  If the method or constructor represented by this instance takes a ref parameter (ByRef in Visual Basic), no special attribute is required for that parameter in order to invoke the method or constructor using this function. Any object in this array that is not explicitly initialized with a value will contain the default value for that object type. For reference-type elements, this value is nulla null reference (Nothing in Visual Basic). For value-type elements, this value is 0, 0.0, or false, depending on the specific element type.

Return Value

Type: System.Object
The return value of the invoked method, or nulla null reference (Nothing in Visual Basic) in the case of a constructor.

Caution:
Elements of the parameters array that represent parameters declared with the ref or out keywords may also be modified.

Public Class A
   Public Overridable Function method() As Integer
      Return 0
   End Function
End Class

Public Class B
   Public Overridable Function method() As Integer
      Return 1
   End Function
End Class

Class Example

   Public Shared Function Demo(ByVal outputBlock As System.Windows.Controls.TextBlock) As Integer
      outputBlock.Text &= "Reflection.MethodInfo" & vbCrLf
      outputBlock.Text &= vbCrLf
      Dim MyA As New A()
      Dim MyB As New B()

      'Get the Type and MethodInfo
      Dim MyTypea As Type = GetType(A)
      Dim Examplea As MethodInfo = MyTypea.GetMethod("method")

      Dim MyTypeb As Type = GetType(B)
      Dim Exampleb As MethodInfo = MyTypeb.GetMethod("method")

      'Get and display the Invoke method
      outputBlock.Text &= String.Format("First method - {0} returns {1}", MyTypea.FullName, _
          Examplea.Invoke(MyA, Nothing).ToString()) & vbCrLf
      outputBlock.Text &= String.Format("Second method - {0} returns {1}", MyTypeb.FullName, _
         Exampleb.Invoke(MyB, Nothing).ToString()) & vbCrLf
      Return 0
   End Function
End Class

' This code produces output similar to the following:
'
'First method - SilverlightApplication.A returns 0
'Second method - SilverlightApplication.B returns 1

using System;
using System.Reflection;

public class A
{
   public virtual int method() { return 0; }
}

public class B
{
   public virtual int method() { return 1; }
}

class Example
{
   public static int Demo(System.Windows.Controls.TextBlock outputBlock)
   {
      outputBlock.Text += "Reflection.MethodInfo\n";
      A MyA = new A();
      B MyB = new B();

      // Get the Type and MethodInfo.
      Type MyTypea = typeof(A);
      MethodInfo Examplea = MyTypea.GetMethod("method");

      Type MyTypeb = typeof(B);
      MethodInfo Exampleb = MyTypeb.GetMethod("method");

      // Get and display the Invoke method.
      outputBlock.Text += "\nFirst method - " + MyTypea.FullName +
          " returns " + Examplea.Invoke(MyA, null);
      outputBlock.Text += "\nSecond method - " + MyTypeb.FullName +
          " returns " + Exampleb.Invoke(MyB, null);
      return 0;
   }
}

/* This code produces output similar to the following:

First method - A returns 0
Second method - B returns 1
 */