Export (0) Print
Expand All

Expression.Throw Method (Expression)

Creates a UnaryExpression that represents a throwing of an exception.

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

public static UnaryExpression Throw(
	Expression value
)

Return Value

Type: System.Linq.Expressions.UnaryExpression
A UnaryExpression that represents the exception.

The following example demonstrates how to create a TryExpression object that uses the Throw method.

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

// A TryExpression object that has a Catch statement. 
// The return types of the Try block and all Catch blocks must be the same.
TryExpression tryCatchExpr =
    Expression.TryCatch(
        Expression.Block(
            Expression.Throw(Expression.Constant(new DivideByZeroException())),
            Expression.Constant("Try block")
        ),
        Expression.Catch(
            typeof(DivideByZeroException),
            Expression.Constant("Catch block")
        )
    );

// The following statement first creates an expression tree, 
// then compiles it, and then runs it. 
// If the exception is caught,  
// the result of the TryExpression is the last statement  
// of the corresponding Catch statement.
Console.WriteLine(Expression.Lambda<Func<string>>(tryCatchExpr).Compile()());

// This code example produces the following output: 
// 
// Catch block

.NET Framework

Supported in: 4.5, 4

.NET Framework Client Profile

Supported in: 4

Portable Class Library

Supported in: Portable Class Library

.NET for Windows Store apps

Supported in: Windows 8

.NET for Windows Phone apps

Supported in: Windows Phone 8.1, Windows Phone Silverlight 8.1, Windows Phone Silverlight 8

Windows Phone 8.1, Windows Phone 8, Windows 8.1, Windows Server 2012 R2, 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.

Show:
© 2014 Microsoft