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UndefinePreprocessorDefinitions Property
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UndefinePreprocessorDefinitions Property

Visual Studio .NET 2003

Specifies one or more preprocessor undefines. Exposes the functionality of the C++ compiler's /U option and the MIDL compiler's /U option.

[Visual Basic .NET]
Public Property UndefinePreprocessorDefinitions() As String
[Visual Basic 6]
Property Get UndefinePreprocessorDefinitions() As String
Property Let UndefinePreprocessorDefinitions( _
   ByVal NewValue As String _
HRESULT __stdcall get_UndefinePreprocessorDefinitions(
   /* [out, retval] */ BSTR* retVal
HRESULT __stdcall put_UndefinePreprocessorDefinitions(
   /* [in] */ BSTR NewValue
public string UndefinePreprocessorDefinitions {get; set;}
[JScript .NET]
public function get UndefinePreprocessorDefinitions() : String
public function set UndefinePreprocessorDefinitions(
   NewValue : String


The following sample code modifies the compiler's UndefinePreprocessorDefinitions property in the development environment:

' add reference to Microsoft.VisualStudio.VCProjectEngine
Imports EnvDTE
Imports Microsoft.VisualStudio.VCProjectEngine

Public Module Module1
    Sub Test()
        Dim prj As VCProject
        Dim cfgs, tools As IVCCollection
        Dim cfg As VCConfiguration
        Dim tool As VCCLCompilerTool
        Dim oldUndefs As String
        prj = DTE.Solution.Projects.Item(1).Object
        cfgs = prj.Configurations
        cfg = cfgs.Item(1)
        tool = cfg.Tools("VCCLCompilerTool")
        oldUndefs = tool.UndefinePreprocessorDefinitions
        tool.UndefinePreprocessorDefinitions = "_DEBUG;" + oldUndefs
    End Sub
End Module

See Samples for Project Model Extensibility for information on how to compile and run this sample.

See Also

Applies To: VCCLCompilerTool Object | VCMidlTool Object

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