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    How do I unlock Foxit Quick PDF Library with my license key?

    Foxit Quick PDF Library

    To unlock Foxit Quick PDF Library so that it is not limited in anyway you need to use the UnlockKey function with your commercial or trial license key after you have initiated the library.

    The UnlockKey function returns a value to indicate whether or not the library could be unlocked:

    0 = The library could not be unlocked
    1 = The library was unlocked successfully

    When using the UnlockKey it’s always a good idea to check the return value of this function so
    that you know whether your application is going to work correctly or not. For example:

    Dim ClassName
    Dim LicenseKey
    Dim FileName 
    
    ClassName = "DebenuPDFLibraryAX[contentblock id=1 img=gcb.png].PDFLibrary"
    LicenseKey = "..." // INSERT LICENSE KEY HERE
    FileName = "C:\Hello-World-From-DQPL.pdf" 
    
    Dim DPL
    Dim Result 
    
    Set DPL = CreateObject(ClassName)
    Result = DPL.UnlockKey(LicenseKey) 
    
    If Result = 1 Then 
       MsgBox "Library version: " + DPL.LibraryVersion
       MsgBox (DPL.LicenseInfo)    Call DPL.DrawText(100, 500, "Hello world from Visual Basic 6") 
    
       If DPL.SaveToFile(FileName) = 1 Then 
         MsgBox "File " + FileName + " written successfully." 
       Else 
         MsgBox "Error, file could not be written." 
       End If 
    
    Else 
       MsgBox "Invalid license key. Please set a valid license key." 
    End If 
    
    Set DPL = Nothing 
    

    If the library is not successfully unlocked then you will run into various problems which will mean your application won’t work correctly. So again, it’s important to check the return value of the UnlockKey function!

    This article refers to a deprecated product. If you are looking for support for Foxit PDF SDK, please click here.