<div>
Edited text of question<br />

</div>


<div>
Oops, &nbsp;this line<br />
<br />
&nbsp;result := chr(asc('0') + ModValue - 1) <br />
<br />
should read<br />
<br />
&nbsp;result := chr(ord('0') + ModValue - 1)<br />
<br />
Cheers,<br />
<br />
Raymond.<br />

</div>


Oops,  this line

 result := chr(asc('0') + ModValue - 1)

should read

 result := chr(ord('0') + ModValue - 1)

Cheers,

Raymond.


<div>
<div class="content wysiwyg-content">
Hello Everyone,<br />
<br />
I am trying to automate a few things here at the office for everyone. One of my projects is to create a simple program (very simple) that calculates the checksum or check digit of an ISBN number.<br />
<br />
For example:<br />
If you had an ISBN number of 157521030, the checksum would be 4. I've seen examples to verify the checksum, and I've seen the mathmatical equation, but I was wondering if anyone had a simple function or routine that does this? Perhaps a pointer to one that does? <br />
<br />
Any help or guidance would be greatly appreciated.<br />
<br />
Sincerely,<br />
<br />
Sandra Wallace<br />
sandra_wallace@yahoo.com<br />
<br />

</div>
</div>


Hello Everyone,

I am trying to automate a few things here at the office for everyone. One of my projects is to create a simple program (very simple) that calculates the checksum or check digit of an ISBN number.

For example:
If you had an ISBN number of 157521030, the checksum would be 4. I've seen examples to verify the checksum, and I've seen the mathmatical equation, but I was wondering if anyone had a simple function or routine that does this? Perhaps a pointer to one that does? 

Any help or guidance would be greatly appreciated.

Sincerely,

Sandra Wallace
sandra_wallace@yahoo.com



Calculate an ISBN checksum?

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