ASIFormDataRequest Undefined symbols Error, frameworks required

ASIHTTPRequest is a very good open-source project, which help you with complicated http requests.

If you are using  ASIFormDataRequest for the first time. You may find the following error:

Undefined symbols: "_CFHTTPAuthenticationIsValid", referenced from: -[ASIHTTPRequest attemptToApplyProxyCredentialsAndResume] in ASIHTTPRequest.o -[ASIHTTPRequest attemptToApplyCredentialsAndResume] in ASIHTTPRequest.o
..........

You may want to add the required frameworks in your project

CFNetwork, SystemConfiguration, MobileCoreServices, and libz.

  

And  "libxml2" which use to parse xml file. 

add  "/usr/include/libxml2" at  "target info" -> "build" tab ->"header search path"