Expression.Call Method (MethodInfo, Expression)

Creates a MethodCallExpression that represents a call to a static (Shared in Visual Basic) method that takes one argument.

Namespace:  System.Linq.Expressions
Assembly:  System.Core (in System.Core.dll)

public static MethodCallExpression Call(
	MethodInfo method,
	Expression arg0
)

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.

ExceptionCondition
ArgumentNullException

method is null.

The following example demonstrates how to create an expression that calls a static (Shared in Visual Basic) method that takes one argument.

// 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()
{

    //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.
    Console.WriteLine(callExpr.ToString());

    // The following statement first creates an expression tree, 
    // then compiles it, and then executes it.
    Console.WriteLine(Expression.Lambda<Func<int>>(callExpr).Compile()());

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

.NET Framework

Supported in: 4.6, 4.5, 4

.NET Framework Client Profile

Supported in: 4

Portable Class Library

Supported in: Portable Class Library

Supported in: Windows Phone 8.1

Supported in: Windows Phone Silverlight 8.1

Supported in: Windows Phone Silverlight 8
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