help with substr

Posted on 2008-06-17
Last Modified: 2010-04-21

I'm trying to work on a check digit routine and need to do 3 things
1) find the length of the variable $paymentReference1
2) set the variable $_toCheck to be all the digits except the last one
3) set the variable $_toMatch to be the last digit

Not sure if the code I have attached is the best way to do this or could it be simpler. Will my code even work?

$paymentReference1 = "10948055";
$_len = strlen($paymentReference1)-1;
$_toCheck = substr($toCheck, 1, $_len);
$_toMatch = substr($toCheck, $_len, 1);

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Question by:Neil Thompson
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LVL 49

Expert Comment

ID: 21806993
Looks fine, 3) can be
$_toMatch = substr($toCheck, -1);
LVL 49

Expert Comment

ID: 21806996
Actually, 2 is incorrect. Should be
$_toCheck = substr($toCheck, 0, $_len);
LVL 48

Accepted Solution

hernst42 earned 500 total points
ID: 21807007
Just try:

$toCheck = $paymentReference1;
$_toCheck = substr($toCheck, 0, -1);
$_toMatch = substr($toCheck, -1);

Author Closing Comment

by:Neil Thompson
ID: 31468124

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