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Forum Discussion

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?

 

application delivery
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devops
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5 Replies

  • Robert_47833's avatar
    Robert_47833
    Icon for Altostratus rankAltostratus
    Nov 22, 2011
    can "?" represent a null or a space?

     

    if I wanna use use another syntax to replace this matches_regex.which one is better?

     

    switch or start_with?

     

    what syntax should I use?

     

    thanks in advance
  • hoolio's avatar
    hoolio
    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
  • Robert_47833's avatar
    Robert_47833
    Icon for Altostratus rankAltostratus
    Nov 22, 2011
    thanks,Aaron

     

    [URI::query "?param1=val1&param2=val2" param1]

     

    the output is "val1"

     

    does it mean this value need to end with "$",the value must be between "=" and "$" ,right?

     

     

    I also wanna to use switch to replace this matches_regex

     

    switch -glob [string tolower [HTTP::query]] {

     

    *gsec=content* {

     

    pool xxxx

     

    }

     

    does it make sense?

     

     

  • nitass's avatar
    nitass
    Icon for Employee rankEmployee
    Nov 22, 2011
    [root@ve1023:Active] config  b rule myrule list
rule myrule {
   when RULE_INIT {
        set test "/test?param1=val1&param2=val2"
        log local0. "\[URI::query $test param1\]: [URI::query $test param1]"
        log local0. "\[URI::query $test param2\]: [URI::query $test param2]"

        switch [string tolower [URI::query $test param1]] {
                "val1" { log local0. "val1" }
                default { log local0. "default" }
        }
}
}

[root@ve1023:Active] config  tail /var/log/ltm
 01:23:09 local/ve1023 err mcpd[23057]: 01020066:3: The requested rule (myrule) already exists in partition Common.
Nov 22 01:23:09 local/tmm info tmm[24220]: Rule myrule : [URI::query /test?param1=val1&param2=val2 param1]: val1
Nov 22 01:23:09 local/tmm info tmm[24220]: Rule myrule : [URI::query /test?param1=val1&param2=val2 param2]: val2
Nov 22 01:23:09 local/tmm info tmm[24220]: Rule myrule : val1