When a database applicaion is using a feature that is not available in prior versions of 4D, such as the 4D Transformation Tag 4DEVAL, and its use is critical to the functioning of the application, it is to wise detect the 4D Application version at startup and take the appopriate action.

It is impotant to know how the version string reads to know the difference between a dot release and an R release. For example, below are the version strings for the 14 dot releases..

• 1400 = 14.0


• 1401 = 14.1


• 1402 = 14.2


• 1303 = 14.3


• 1404 = 14.4

Below are the version strings for the v14 R releases

• 1420 = 14 R2


• 1430 = 14 R3


• 1440 = 14 R4


• 1450 = 14 R5

Since the 4D Transformation Tag 4DEVAL was introduced in v14 R4 the code below will prevent any prior version of 4D from running the application.

C_TEXT($Vers_T:) C_LONGINT($Ndx) $Vers_T:=Application version If ($Vers_T<"1440") // v14.4 is 1404    // Warn that the application is too old and a newer version has to be used    //    ALERT("The application requires 4D v14 R4 or newer.\rThe applicaiton will now quit.")    QUIT 4D Else    // Start the application End if