I'm learning how to using AFNetworking for iOS.I often use ASIHttprequest to upload a file and post multiple params at the same time before,it's simple using ASIHttprequest like this.

```
[request setPostValue:distanceLabel.text forKey:@"km"];
[request setPostValue:speedValue forKey:@"speed"];
[request setFile:filePath forKey:@"filedata"];

```

I learn a lot about AFNetworking,but I don't know how to do yet.Please show me the code.Thanks!