How to select a random parameter captured using
web_reg_save_param("varParamName",
"LB=value=\"",
"RB=\"",
"Ord=All",
LAST);
Your LB and RB conditions are too generic. Pick something more specific to what you are trying to capture
To your greater question, there are several paths on picking an ordinal depending upon your version of LoadRunner. Something which works for every version would be
char foo[50];
...
sprintf(
foo,
"{varParamName_%d}",
rand() * atoi( lr_eval_string("{varParamName_count}" ) ) +1
);
...
lr_save_string(
lr_eval_string( foo ),
"LR_MyRandomCorrelatedvariable"
);
...
lr_output_message(
"%s",
lr_eval_string( "{LR_MyRandomCorrelatedvariable}" )
);