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[Allen Shaw]

On 09/08/2010 07:30 AM, ps at blu-studio.com wrote:
> Using GNU Regular Expressions I need to examine an URL like those 
> below, checking the size key and value, I need to capture and block 
> all URLs where 'size does not equal 10'. In other words "size=12", not 
> acceptable.
> ...
> All around size, the other key and value pairs can be there, not be 
> there, be in a different order, and the doamin and directory path 
> combination may be different too.
>
> Any good regexps for this?
The following regex pattern works, though you might need to tweak its 
syntax for your particular parser -- meaning, I'm not real sure this is 
"GNU Regular Expression" syntax.  For example, \y for a word boundary 
may not be correct, but if you can support word boundaries, you can 
tweak this for syntax.  Sure would like to hear from you if it works or not.

/http:\/\/[^?]+\?.*\ysize=10\y/

that is:

/
     opening delimiter
http:\/\/
     literal "http://",
[^?]+
     one or more of anything other than a literal "?"
\?
     a literal "?"
.*
     zero or more of any character
\y
     a word boundary
size=10
     literal "size=10"
\y
     a word boundary
/
     closing delimiter

If it matches this regex, it's an http URI with query string having 
variable "size" equal to "10".  If you need it also to match https URIs, 
use this:
/https?:\/\/[^?]+\?.*\ysize=10\y/


-- 
Allen Shaw
TwoMiceAndAStrawberry.com

"Excellence in Web software development and design"

allen at TwoMiceAndAStrawberry.com
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