Otherwise Element (MSBuild)

项目
11/15/2016

Note

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Specifies the block of code to execute if and only if the conditions of all When elements evaluate to false.

<Project>
<Choose>
<When>
<Choose>
...
<Otherwise>
<Choose>
...

Syntax

<Otherwise>  
    <PropertyGroup>... </PropertyGroup>  
    <ItemGroup>... </ItemGroup>  
    <Choose>... </Choose>  
</Otherwise>

Attributes and Elements

The following sections describe attributes, child elements, and parent elements.

Attributes

None.

Child Elements

Element	Description
Choose	Optional element. Evaluates child elements to select one section of code to execute. There may be zero or more `Choose` elements in an `Otherwise` element.
ItemGroup	Optional element. Contains a set of user-defined Item elements. There may be zero or more `ItemGroup` elements in an `Otherwise` element.
PropertyGroup	Optional element. Contains a set of user-defined Property elements. There may be zero or more `PropertyGroup` elements in an `Otherwise` element.

Parent Elements

Element	Description
Choose	Evaluates child elements to select one section of code to execute.

Remarks

There may be only one Otherwise element in a Choose element, and it must be last element.

The Choose, When, and Otherwise elements are used together to provide a way to select one section of code to execute out of a number of possible alternatives. For more information, see Conditional Constructs.

Example

The following project uses the Choose element to select which set of property values in the When elements to set. If the Condition attributes of both When elements evaluate to false, the property values in the Otherwise element are set.

<Project  
    xmlns="https://schemas.microsoft.com/developer/msbuild/2003" >  
    <PropertyGroup>  
        <Configuration Condition="'$(Configuration)' == ''">Debug</Configuration>  
        <OutputType>Exe</OutputType>  
        <RootNamespace>ConsoleApplication1</RootNamespace>  
        <AssemblyName>ConsoleApplication1</AssemblyName>  
        <WarningLevel>4</WarningLevel>  
    </PropertyGroup>  
    <Choose>  
        <When Condition=" '$(Configuration)'=='debug' ">  
            <PropertyGroup>  
                <DebugSymbols>true</DebugSymbols>  
                <DebugType>full</DebugType>  
                <Optimize>false</Optimize>  
                <OutputPath>.\bin\Debug\</OutputPath>  
                <DefineConstants>DEBUG;TRACE</DefineConstants>  
            </PropertyGroup>  
            <ItemGroup>  
                <Compile Include="UnitTesting\*.cs" />  
                <Reference Include="NUnit.dll" />  
            </ItemGroup>  
        </When>  
        <When Condition=" '$(Configuration)'=='retail' ">  
            <PropertyGroup>  
                <DebugSymbols>false</DebugSymbols>  
                <Optimize>true</Optimize>  
                <OutputPath>.\bin\Release\</OutputPath>  
                <DefineConstants>TRACE</DefineConstants>  
            </PropertyGroup>  
        </When>  
        <Otherwise>  
            <PropertyGroup>  
                <DebugSymbols>true</DebugSymbols>  
                <Optimize>false</Optimize>  
                <OutputPath>.\bin\$(Configuration)\</OutputPath>  
                <DefineConstants>DEBUG;TRACE</DefineConstants>  
            </PropertyGroup>  
        </Otherwise>  
        </Choose>  
    <Import Project="$(MSBuildBinPath)\Microsoft.CSharp.targets" />  
</Project>

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