Run External Application in Visual FoxPro

In Visual FoxPro, the best way to run an external application is by using the ShellExecute() API function.

For the complete explanation on the ShellExecute() function, please refer to this Foxite's article .

To make things easy, I put all the codes into a program PRG. Whenever I need to call an external application, I just run this procedure.

********************************************************************
* Program: runexapp.prg
* Purpose: Procedure to execute an external application, with parameters.
* Usahe  : DO runexapp WITH , 
********************************************************************

PARAMETERS In_App, In_Params

IF TYPE("In_Params") <> "C"
    In_Params = ""
ENDIF

** Declare API function (only need to declare once in main.prg).
DECLARE INTEGER ShellExecute IN shell32.DLL ;
    INTEGER hndWin, ;
    STRING cAction, ;
    STRING cFileName, ;
    STRING cParams, ;
    STRING cDir, ;
    INTEGER nShowWin
**

cAction   = "open"
cFileName = In_App
cParams   = In_Params
cPath     = ""

mRtn      = ShellExecute(0,cAction,cFileName,cParams,cPath,1)

** Extra checking.
DO CASE
    CASE mRtn = 2
        mMsg = "Bad Association"
    CASE mRtn = 29
        mMsg = "Failure to load application"
    CASE mRtn = 30
        mMsg = "Application is busy"
    CASE mRtn = 31
        mMsg = "No application association"
    OTHERWISE
        mMsg = ""
ENDCASE

IF !EMPTY(mMsg)
    MESSAGEBOX(mMsg,48,"Error")
ENDIF

CLEAR DLLS ShellExecute
**

}

To use the procedure, just put a single line in your program:

DO runexapp WITH 'c:\program\someapp.exe'

You can pass the optional parameters as the second arguments if needed.