Was this page helpful?
Your feedback about this content is important. Let us know what you think.
Additional feedback?
1500 characters remaining
Export (0) Print
Expand All

MSBuild Conditional Constructs

MSBuild provides a mechanism for either/or processing with the Choose, When, and Otherwise elements.

The Choose element contains a series of When elements with Condition attributes that are tested in order from top to bottom until one evaluates to true. If more than one When element evaluates to true, only the first one is used. An Otherwise element, if present, will be evaluated if no condition on a When element evaluates to true.

Choose elements can be used as child elements of Project, When and Otherwise elements. When and Otherwise elements can have ItemGroup, PropertyGroup, or Choose child elements.

The following example uses the Choose and When elements for either/or processing. The properties and items for the project are set depending on the value of the Configuration property.

<Project xmlns="http://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>
    </Choose>
    <!-- Rest of Project -->
</Project>
Show:
© 2015 Microsoft