Expression.Call Method (MethodInfo, Expression)

Parameters

• method
  Type: System.Reflection.MethodInfo
  A MethodInfo to set the Method property equal to.

• arg0
  Type: System.Linq.Expressions.Expression
  The Expression that represents the first argument.

Return Value

Type: System.Linq.Expressions.MethodCallExpression
A MethodCallExpression that has the NodeType property equal to Call and the Object and Method properties set to the specified values.

        ' Add the following directive to your file:
        ' Imports System.Linq.Expressions  
        Public Class SampleClass
            Shared Function Increment(ByVal arg1 As Integer) As Integer
                Return arg1 + 1
            End Function
        End Class
        Shared Sub TestCall()
            'This expression represents a call to an instance method with one argument.
            Dim callExpr As Expression = Expression.Call(
                GetType(SampleClass).GetMethod("Increment"),
                Expression.Constant(2))

            ' Print the expression.
            outputBlock.Text &= callExpr.ToString() & vbCrLf

            ' The following statement first creates an expression tree,
            ' then compiles it, and then executes it.
            outputBlock.Text &= Expression.Lambda(Of Func(Of Integer))(callExpr).Compile()() & vbCrLf
        End Sub

        ' This code example produces the following output:
        '
        ' Increment(2)
        ' 3

// Add the following directive to your file:
// using System.Linq.Expressions;  

public class SampleClass
{
   public static int Increment(int arg1)
   {
      return arg1 + 1;
   }
}

static public void TestCall(System.Windows.Controls.TextBlock outputBlock)
{

   //This expression represents a call to an instance method with one argument.
   Expression callExpr = Expression.Call(
                           typeof(SampleClass).GetMethod("Increment"),
                           Expression.Constant(2)
                       );

   // Print out the expression.
   outputBlock.Text += callExpr.ToString() + "\n";

   // The following statement first creates an expression tree,
   // then compiles it, and then executes it.
   outputBlock.Text += Expression.Lambda<Func<int>>(callExpr).Compile()() + "\n";

   // This code example produces the following output:
   //
   // Increment(2)
   // 3
}