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jmoskie

Catching Array Out of Bounds Errors?

4 posts in this topic

My script does some screen scraping from an application. It gets the text, and then it goes through it line by line.

The format is generally

User

Joe

San Jose

California

555-555-5555

If it finds a keyword string, such as "User", it knows something about the next few lines, as the format is standard.

When it's looking at $lines[$l] and finds "User", it knows that $lines[$l+1] is the user's name, $lines[$l+2] is the user's city, etc.

The problem I'm facing now is handling what happens when the application I'm screen scraping disappears. If you exit that program, it's possible that I get a partial screen scrape, such as:

User

Joe

Then, when I reference $lines[$l+2] to get the city, I get an array out of bounds exception.

I've started adding some bounds checking into the code, but I was hoping there would be a way to "catch" these and handle them properly. Is there?

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#2 ·  Posted (edited)

Do a UBound() check on the array before you start trying to access it.

If Ubound($lines) > $l+2 Then

;Do your accessing here

Else

;Do your error handling here

Endif

Where $l+2 is the greatest value that will be accessed in the array in the If Then statement.

- The Kandie Man ;-)

EDIT: Fixed comparison operator

Edited by The Kandie Man

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#3 ·  Posted (edited)

Hi,

check size of array:

e.g.:

If (UBound ($lines) - 1) < ($I + 4) Then MsgBox (0,"","Invalid array size!")

;-))

Stefan

P.S: You might post some code to get further help!

P.S.S: haha, double post.....

Edited by 99ojo

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$iUbound = Ubound($array) -1

Then in the loop you are using

If $i+1 <= $iUbound Then.... Whatever

If $i+2 <= $iUbound Then.... Whatever

Etc.

If you don't want any info entered if the last group is not complete then you can make it easier.

For $i = 1 To $ibound

If $i+4 > $iUbound Then ExitLoop

;Your regular code goes here

Next


George

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