How to run the http request ( based on the regular expression output from previous http request )by adding if controller

Question

I have a regular expression ${Fax} in the http request1 which returns a value Ex: b4mL0000000NDKF and I would like to add a if controller in the next http request2 so it can only run if the reg exp from previous http request1 i.e., ${Fax} returns a value otherwise (if the regexp from http request1 returns 'Match count: 0'), I don't want to run the http request2 (because I am using the value of reg exp ${Fax} in the next http request --> Path)

Could you tell me the condition that I can write in the If Controller which controls the http request2.

Thanks.

Answer 1

Since JMeter 4.0 you have __isVarDefined() function which returns true or false depending whether the given variable is defined or not.

So you can use ${__isVarDefined(Fax)} expression as the If Controller condition