Expression<TDelegate>.Compile Method

The Compile method produces a delegate of type TDelegate at runtime. When that delegate is executed, it has the behavior described by the semantics of the Expression<TDelegate>.

The Compile method can be used to obtain the value of any expression tree. First, create a lambda expression that has the expression as its body by using the Lambda method. Then call Compile to obtain a delegate, and execute the delegate to obtain the value of the expression.

The following code example demonstrates how Compile is used to execute an expression tree.

            // Lambda expression as data in the form of an expression tree.
            System.Linq.Expressions.Expression<Func<int, bool>> expr = i => i < 5;
            // Compile the expression tree into executable code.
            Func<int, bool> deleg = expr.Compile();
            // Invoke the method and print the output.
            Console.WriteLine("deleg(4) = {0}", deleg(4));

            /*  This code produces the following output:

                deleg(4) = True
            */

.NET Framework

.NET Framework Client Profile

Portable Class Library

.NET for Windows Store apps

Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

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