The MsiEvaluateCondition function evaluates a conditional expression containing property names and values.

Syntax

MSICONDITION MsiEvaluateCondition(
  __in  MSIHANDLE hInstall,
  __in  LPCTSTR szCondition
);

Parameters

hInstall [in]

Handle to the installation provided to a DLL custom action or obtained through MsiOpenPackage, MsiOpenPackageEx, or MsiOpenProduct.

szCondition [in]

Specifies the conditional expression. This parameter must not be null. For the syntax of conditional expressions see Conditional Statement Syntax.

Return Value

MSICONDITION_ERROR

An invalid handle was passed to the function, or the conditional expression has a syntax error.

MSICONDITION_FALSE

An expression that evaluates to FALSE was passed to the function.

MSICONDITION_NONE

No expression was passed to the function.

MSICONDITION_TRUE

An expression that evaluates to TRUE was passed to the function.

Remarks

The following table shows the feature and component state values used by the MsiEvaluateCondition function. These states are not set until MsiSetInstallLevel is called, either directly or by the CostFinalize action. Therefore, state checking is generally only useful for conditional expressions in an action sequence table.

Requirements

See Also

Installer Action Functions

Passing Null as the Argument of Windows Installer Functions

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Build date: 11/12/2009