Millisecond Forums

I am using an online service to recruit participants and hosting my surveys on Inquisit web. I want to generate a random alpha-numeric code on Inquisit that will be displayed to my participants upon completion of my study. They will then input that alpha-numeric code into the other platform to connect the data in both programs. I am struggling with how to do this because whatever code is provided to the participants must also be recorded in the data on Inquisit. I must have the code saved in both platforms otherwise I cannot connect their data. The other issue is that I need this code to appear even if they quit prior to completing the study (e.g., hit Cntrl+Q before they go through all of the survey pages). Help please?