Re: Slow string

I can confirm what Mayayana said; it doesn't really matter - the code is actually quite fast, Ernst. : )
Some numbered questions below, and also a couple of comments on the general problem and suggestions for things you _might_ want to do to make your code simpler or run faster.

(1) Execution time and questions
I see virtually no difference in execution time for the code you posted when using cscript versus using wscript; to confirm, I bracketed the code with an initial
t0 = timer
and, in the check for arguments, the following line
WScript.Echo (timer - t0)

This shows about 10-20 ms delay maximum, and sometimes "0". This is actually a bogus value, since the limits of resolution are about 20 ms - so all that establishes is that it's "really, really fast".

NOTE - this tells us about the time taken from when the script _begins_to_execute_ to when it is ready to exit. So other issues, such as the launch method, aren't considered. An important question here is: Are you actually entering the script name into a console window (possibly with cscript explicitly used in a command)? Or are you simply performing point-and-click startup - and if that is the case, are you seeing most of the initial delay happening _before_ the console window appears?

If it's the latter, the lag is occurring in the console window spawning, which isn't due to WSH itself. I suspect that this may be the real issue. The real workaround for this is to simply run it from a console window.

(2) Cleaner (and faster) console script execution with a wrapper
Another startup technique that ensures the host is cscript, prevents input pipeline breaking, and coincidentally shaves off a tiny bit of startup time is to use a wrapper .cmd script the same way that Perl and a few other console script environments do. Here's all you need to do. In the same folder as the VBScript, put in a .cmd file with the same base name and one line of content. If your script is called AddData.vbs, you would use the name AddData.cmd (or AddData.bat) and it would contain the line

@cscript //Nologo %~dpn0.vbs %*

You can use the exact same line for every wrapper script - and that includes wsf and js scripts; all you need to do is change the final "vbs" to "wsf" or "js" as appropriate.

(3) String building - nonlinear, but not enough to matter here
If you build a large string by small concatenations, the performance degrades geometrically - so does array resizing, because they both use the same nasty technique inherited from VB1 of copying the entire data structure to a new structure with the added element. So adding 1 character to a string with 10000 characters takes 10,000 times as long as adding it to a string with only 1 character. However, even this is pretty fast and only matters if you're doing it thousands of times. I don't think your problem is your stringbuilding technique.

(4) Speeding up startup (and execution) internally
This won't matter a great deal in most cases, but if you use Option Explicit (without On Error Resume Next following it, of course) you do get faster dynamic compilation and execution. This is because identifier lookup can happen much more rapidly.

(5) WSFs for help display
Based on what you've done here, I suspect you would LOVE using a WSF file structure instead. You can include string blocks as resources, but even better you can provide a runtime block of help text and a simple list of arguments. The WSF will actually create the correctly-formatted help string (including marking for whether an item is mandatory or optional, boolean/simple/string values, and even the WSF's own name).
The critical thing is that if you do want to provide an explanatory paragraph or two, you just write it in the correct block as plain text with no need for special ways to write tabs/quotes/etc.

(6) VBScript values
Not relevant if you switch to a WSF, but you can do a couple of the symbols more easily. There's a built-in vbTab and a CR+LF combo is either vbCrLf or vbNewLine.



"Ernst Guckel" <ErnstGuckel@xxxxxxxxxxxxxxxxxxxxxxxxx> wrote in message news:58604BF4-1835-4EE7-B936-66905915E59D@xxxxxxxxxxxxxxxx
hmm... Yes with Wscript it works a lot faster than Cscript. being its a CLI
utility i have it run with cscript. Is there a difference in execution time
between the two? And is a few second delay exceptable under normal
circumstances?

Thanks again,
Ernst.


"mayayana" wrote:

That's not the code in question. It works instantly for me.
All it's doing is building a string and showing a msgbox.
So why would you assume that's the problem?

String concatenation is slow. If you had to construct that
same string 10,000 times it might be worth putting the
substrings into an array and Join-ing them with vbCrLf, but the
amount of concatenation you're doing is not significant.

> I wrote a cli script to track usage in a database. The script runs > fine
> except if you execute it without any options it returns the command > syntax
> like it should but it is VERY SLOW. It takes about 4 seconds to output > it
to
> the screen. I can open the database, add a new record, open the log > file
and
> add a new log entry in about 1 second... I know that using a lot of &s
can
> slow it down but how else do I build the string? Here is the code in
> question:
>
> Thanks,
> Ernst
>
> strQuote = Chr(34)
> strTab = Chr(9)
> strNext = vbCr & vbLf
>
> AbsPathINI = AbsPath & > Left(WScript.ScriptName,Len(WScript.ScriptName)-3)
&
> "ini"
>
> strSyntax = " Syntax for the Script is as follows:" & strNext & strNext > _
> & " " & WScript.ScriptName & strTab & "/t:{Image Tag} [/a > /s:{Tag
> Description} | /r | /R] " & strNext _
> & strTab & strTab & "[/i:{INI File}] [/c:{Count}] [/d:{Last > Access
> Date}]" & strNext _
> & strTab & strTab & "[/l:{Log File}]" & strNext & strNext _
> & " Update mode will be used unless one of the 'Mode Switches'
(/a,
> /r, or /R)" & strNext _
> & " is used. Combining the 'Mode Switches' will result in the
last
> one" & strNext _
> & " provided being used." & strNext & strNext _
> & " Options:" & strNext & strNext _
> & " /a" & strTab & strTab & strTab & " - Add a new tag.
Must
> be combined with the" & strNext _
> & strTab & strTab & strTab & " '/s' switch" & strNext _
> & " /r" & strTab & strTab & strTab & " - To retrieve tag
data
> for a specific tag." & strNext _
> & strTab & strTab & strTab & " Used with the '/t' > switch."
> & strNext _
> & " /R" & strTab & strTab & strTab & " - Retrieve ALL tag
> data. No other switches " & strNext _
> & strTab & strTab & strTab & " are required." & strNext > _
> & " /t:{Image Tag}" & strTab & strTab & " - Tag to be > updated /
> added to the " & strNext _
> & strTab & strTab & strTab & " database. This switch is
> required." & strNext _
> & " /c:{Count}" & strTab & strTab & " - User provided > tag
> count. Used to reset " & strNext _
> & strTab & strTab & strTab & " or force the count to a
> specific value." & strNext _
> & " /d:{Last Access Date}" & strTab & " - User provided > 'Last
> Accessed Date.' The " & strNext _
> & strTab & strTab & strTab & " default is today's date." &
> strNext _
> & " /i:{INI file}" & strTab & strTab & " - INI file with
> relative path. The default is" & strNext _
> & strTab & strTab & strTab & " " &
> Left(WScript.ScriptName,Len(WScript.ScriptName)-3) & "ini " _
> & "in the current directory." &
> strNext _
> & " /l:{Log File}" & strTab & strTab & " - Log file with
> relative path. This " & strNext _
> & strTab & strTab & strTab & " switch overrides settings > in
> the INI " & strNext _
> & strTab & strTab & strTab & " file. Default output is to
> the console." & strNext _
> & " /s:{Tag Description}" & strTab & " - Description of > tag.
> This switch is " & strNext _
> & strTab & strTab & strTab & " required with the '/a'
> switch." & strNext & strNext _
> & " Make sure to enclose string values in quotes."
>
>
> ' Check for 0 arguments and return syntax if true
> If WScript.Arguments.Count = 0 Then
> ' Syntax for script
> WScript.echo strSyntax
> WScript.Quit
> End If



.

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