 |
 | Home | Contact Us | FAQ | Search & Site Map | Link to Us |
 | Sign In | Join | Other 45 Sites in Network |
VB Forum / COM / January 2004Problem with VB's Shell command (on Win2K only ) ???
Hi all, I need to execute Notepad.exe with the following routine : Public Const HKEY_LOCAL_MACHINE = &H80000002 Dim lHandleKey As Long Dim sResult As String * 256 lHandleKey = 256 Call RegOpenKey(HKEY_LOCAL_MACHINE, "SOFTWARE\Classes\txtfile\shell\open\command", lHandleKey) Call RegQueryValueEx(lHandleKey, "", 0, 0, sResult, 256) If Len(Trim(sResult)) > 0 Then Call Shell(s_fctGetAPIResult(sResult, "%1") & sFileName, vbNormalFocus) Exit Sub End If Public Function s_fctGetAPIResult(sApiResult As String, Optional sToFind As String) Dim lPos As Long If Len(Trim(sToFind)) < 1 Then sToFind = Chr(0) lPos = InStr(1, sApiResult, sToFind, 1) s_fctGetAPIResult = IIf(lPos > 0, Left(sApiResult,lPos - 1), "") End Function The above code runs well on Win98 but when I try to run them on Win2K it always throws message "File Not Found". I also try ShellExecute API with the same result. If I try with absolute path it runs well on both platforms. Any ideas ? Thanks in advance Setya > The [...] code runs well on Win98 but when I try to run them on Win2K > it always throws message "File Not Found". I also try ShellExecute [quoted text clipped - 7 lines] > > Setya Setya - Did you try the obvious thing, and stepped over each line of your code in the IDE? For instance, what is the value of sResult, or s_fctGetAPIResult(sResult) for that matter? This value is obviously the one which is wrong. Now work back to find the real problem. Having given you that bit of advice, I can't give you the answer (there are far too many unknowns), however I can comment on your code style and useages. This looks like code that has been crudely ported from Win16 i.e. Windows 3.1. There are things that you should change anyway: > Public Const HKEY_LOCAL_MACHINE = &H80000002 > > Dim lHandleKey As Long > Dim sResult As String * 256 * Don't use: Dim sResult As String * 256. Instead, declare this as a normal string, and then do: sResult = Space$(256). You should only use Fixed length strings inside a User Defined Type. > lHandleKey = 256 * What's the point of setting this to 256? This value will be written over by the next function without reading this. > Call RegOpenKey(HKEY_LOCAL_MACHINE, > "SOFTWARE\Classes\txtfile\shell\open\command", > lHandleKey) * Don't use: RegOpenKey(), use RegOpenKeyEx(). The documentation says that RegOpenKey() is only there for backwards compatibility. * Don't use: *Call* RegOpenKey(). Both open key versions return a Long value which you should examine. Only if it is ERROR_SUCCESS, should you continue with the next line. > Call RegQueryValueEx(lHandleKey, "", 0, 0, sResult, 256) * You should also examine the return value of RegQueryValueEx(), and only continue if it returns ERROR_SUCCESS. * The last parameter should be a Long variable, rather than a constant, because it rather helpfully returns the numbers of characters copied into sResult. This way, you can simply use Left$(lLenResult - 1) to give you the string you want, rather than using your s_fctGetAPIResult() function. * Minor quibble: in this case, you are better off using the constant vbNullString, rather than "" for the key name. > If Len(Trim(sResult)) > 0 Then * You shouldn't be using this test to determine whether the functions succeeded. RegQueryValueEx() has helpfully given you a return code.. Use it. > Call Shell(s_fctGetAPIResult(sResult, "%1") > & sFileName, vbNormalFocus) [quoted text clipped - 3 lines] > Public Function s_fctGetAPIResult(sApiResult As String, Optional > sToFind As String) * I know that I have said that you shouldn't need to use this routine, however I ought to point out that you should type the return value of the value to be "As String", otherwise it treats it converts your string to a variant. > Dim lPos As Long > > If Len(Trim(sToFind)) < 1 Then sToFind = Chr(0) * Likewise, in future use Trim$() rather than Trim(), because it converts the string to a Variant. * Actually, I have just noticed that you can effectively combine the previous line with the function header to get: Public Function s_fctGetAPIResult(sApiResult As String, Optional sToFind As String = vbNullChar) > lPos = InStr(1, sApiResult, sToFind, 1) > > s_fctGetAPIResult = IIf(lPos > 0, > Left(sApiResult,lPos - 1), "") > End Function Finally, there is a small possibility that your declarations for the API calls might be slightly iffy. > *** Sent via Developersdex http://www.developersdex.com *** Just interested, but what's the deal with this Developersdex? I find it slightly annoying that they often email me when I get something answered on a tech newsgroup. > Don't just participate in USENET...get rewarded for it! Crikey! What have I been missing? Personally, using Newsgroup s/w seems a far more efficient way of accessing USENET. I don't use DevX any more for exactly that reason. -- Mark Bertenshaw Kingston upon Thames UK Thanks for the reply, Actually I only inherit the code, it was written by programmer before me. But I'll try to fix it to conform your advice. Best Regards, Setya |
Reply to this Message |
 Sign In
 Join
 My Latest Posts My Monitored Threads My Blog My Photo Gallery My Profile My Homepage Start New Thread Enable EMail Alerts Rate this Thread
|
©2009 Advenet LLC Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.