title: objective c ios http request sent not encoded string
body: <p>Is it possible to set as http body not encoded string?</p>
  
  <pre><code>  NSData *postData = [postString dataUsingEncoding:NSUTF8StringEncoding allowLossyConversion:YES];
  
    NSString *postLength = [NSString stringWithFormat:@"%d", [postData length]];
  
    [request setValue:postLength forHTTPHeaderField:@"Content-Length"];
    [request setHTTPBody:postData];
  </code></pre>
  
  <p>Is it possible to do something like this:</p>
  
  <pre><code>  NSString *postLength = [NSString stringWithFormat:@"%d", [postString length]];
    [request setValue:postLength forHTTPHeaderField:@"Content-Length"];
    [request setHTTPBody:postString];
  </code></pre>
  
  <p>I had tried  this and got an error :
  Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFString bytes]: unrecognized selector sent to instance </p>