IInstalledDllFunctionCallCustomAction 
Declaration
IInstalledDllFunctionCallCustomAction: ICustomAction
Overview
This interface facilitates editing custom action for calling function from installed native dll .
Properties
IFile InstalledDll - Gets or sets the installed dll file of the custom action.
String FunctionName - Gets or sets the name of a function to call .
String ActionData - Gets or sets the value of the CustomActionData property. This property can be retrieved as a regular property inside Deferred custom actions and it is available only for DLL, JScript and VBScript custom actions. A common usage scenario is to use the CustomActionData property in Rollback Custom Actions since they are also deferred .
Example
$advinst = new-object -com AdvancedInstaller
$project = $advinst.CreateProjectS(“architect”)
$dllFile = $project.FilesComponent.AddFileS("appdir\my_app", "D:\test.dll")
$custAct = $project.CustomActionsComponent.NewInstalledNativeDllFunctionCall($dllFile)
$custAct.FunctionName = "ExecuteTest"