Regex Search and Replace in LoadRunner

Previously I identified how to setup pattern matching with Regex in LoadRunner.

Here’s how you implement search and replace functionality with the same POSIX libraries used in the previous example.

Create a replace function in your favourite headers file or wherever you keep your framework’y stuff… You also need the pcre3.dll and pcreposix.h header added as files to your script.

replace(const char *string, char *pattern, char *replace, char *match)
{
 
   int length;
   int  status;
   int  eflag;
   char buf[1024] = "";
   char out[1024] = "";
 
   regex_t re;
   regmatch_t pmatch[128];
   lr_load_dll("pcre3.dll");
 
   if((status = regcomp(&re, pattern, REG_EXTENDED)) != 0){
      regerror(status, &re, buf, 120);
      lr_output_message("Match PCRE Exit 2");
      return 2;
   }
 
   while(status = regexec( &re, string, 1, pmatch, eflag)== 0){
      strncat(out, string, pmatch[0].rm_so);
      strcat(out, replace);
      string += pmatch[0].rm_eo;
      eflag = REG_NOTBOL;
   }
   strcat(out, string);
   lr_save_string(out, match);
}

Then anywhere in your actions you can call on this function, passing it the string buffer you wish to operate on, a search value, a replace value and the name of the LoadRunner parameter you want the result saved into.

lr_save_string("FOO%20BAR%20DING", "buffer");
replace(lr_eval_string("{buffer}"),"%20"," ", "custom");

What you’ll end up with is something like this:


Home.c(6): Notify: Saving Parameter "buffer = FOO%20BAR%20DING"
Home.c(7): Notify: Parameter Substitution: parameter "buffer" = "FOO%20BAR%20DING"
framework.h(135): Notify: Saving Parameter "custom = FOO BAR DING"


Enjoy.