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Robert_47833's avatar
Robert_47833
Icon for Altostratus rankAltostratus
Nov 22, 2011

how to understand this syntax "?" in matches_regex

if {$queryString matches_regex "(?i)gsec=content"} {   other code   }     I don't know the what "?" represent in this syntax   does it mean 0 or 1 single character?  
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hooleylist's avatar
hooleylist
Icon for Cirrostratus rankCirrostratus
Nov 22, 2011
Hi Jucao,

 

 

(?i) sets case insensitive for the rest of the match:

 

http://www.regular-expressions.info/tcl.html

 

 

If you want to check the query string for a parameter of gsec being set to content, you could use URI::query:

 

 

if {[string tolower [URI::query [HTTP::uri] gsec]] eq "content"}{

 

 

In general, string operations will be 5-10 times more efficient than regexes.

 

 

Aaron