• Article

SwitchCase Class

Microsoft Silverlight will reach end of support after October 2021. Learn more.

Represents one case of a SwitchExpression.

Inheritance Hierarchy

System.Object
  System.Linq.Expressions.SwitchCase

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

Syntax

'Declaration
Public NotInheritable Class SwitchCase

public sealed class SwitchCase

The SwitchCase type exposes the following members.

Properties

  Name Description
Public property Body Gets the body of this case.
Public property TestValues Gets the values of this case. This case is selected for execution when the SwitchValue matches any of these values.

Top

Methods

  Name Description
Public method Equals(Object) Determines whether the specified Object is equal to the current Object. (Inherited from Object.)
Protected method Finalize Allows an object to try to free resources and perform other cleanup operations before the Object is reclaimed by garbage collection. (Inherited from Object.)
Public method GetHashCode Serves as a hash function for a particular type. (Inherited from Object.)
Public method GetType Gets the Type of the current instance. (Inherited from Object.)
Protected method MemberwiseClone Creates a shallow copy of the current Object. (Inherited from Object.)
Public method ToString Returns a String that represents the current Object. (Overrides Object.ToString().)
Public method Update Creates a new expression that is like this one, but using the supplied children. If all of the children are the same, it will return this expression.

Top

Examples

The following example demonstrates how to create an expression that represents a switch statement without a default case by using the SwitchCase method.

' Add the following directive to the file:
' Imports System.Linq.Expressions

' An expression that represents the switch value.
Dim switchValue As ConstantExpression = Expression.Constant(2)

' This expression represents a switch statement 
' without a default case.
Dim switchExpr As SwitchExpression =
Expression.Switch(
    switchValue,
    New SwitchCase() {
        Expression.SwitchCase(
            Expression.Call(
                Nothing,
                GetType(Console).GetMethod("WriteLine", New Type() {GetType(String)}),
                Expression.Constant("First")
            ),
            Expression.Constant(1)
        ),
        Expression.SwitchCase(
            Expression.Call(
                Nothing,
                GetType(Console).GetMethod("WriteLine", New Type() {GetType(String)}),
                Expression.Constant("Second")
            ),
            Expression.Constant(2)
        )
    }
)

' The following statement first creates an expression tree,
' then compiles it, and then runs it.
Expression.Lambda(Of Action)(switchExpr).Compile()()

' This code example produces the following output:
'
' Second

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

// An expression that represents the switch value.
ConstantExpression switchValue = Expression.Constant(2);

// This expression represents a switch statement 
// without a default case.
SwitchExpression switchExpr =
    Expression.Switch(
        switchValue,
        new SwitchCase[] {
               Expression.SwitchCase(
                   Expression.Call(
                       null,
                       typeof(Console).GetMethod("WriteLine", new Type[] { typeof(String) }),
                       Expression.Constant("First")
                   ),
                   Expression.Constant(1)
               ),
               Expression.SwitchCase(
                   Expression.Call(
                       null,
                       typeof(Console).GetMethod("WriteLine", new Type[] { typeof(String) }),
                       Expression.Constant("Second")
                   ),
                   Expression.Constant(2)
               )
           }
    );

// The following statement first creates an expression tree,
// then compiles it, and then runs it.
Expression.Lambda<Action>(switchExpr).Compile()();

// This code example produces the following output:
//
// Second

Version Information

Silverlight

Supported in: 5, 4

Platforms

For a list of the operating systems and browsers that are supported by Silverlight, see Supported Operating Systems and Browsers.

Thread Safety

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.