RestKit: how to change RKRequest body string from JSON to plain text?
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I need to post some request with the format of body:

username=<(some user name)>&password=<(some password)>

and the response string is in JSON format.

but when I create the object mapping, the body string is:

{"username":"<(some user name)>","password":<(some password)>}

Is there a way I can change the format of request body?

Thanks!