NSMutableURLRequest实现Post访问

-(void)PostStr
{
    NSString *urlstring= @"http://116.255.130.35:11011/api/TestApi2/PostFromPosData";
    NSString *poststr=@"hellowrold";
    NSURL *url=[NSURL URLWithString:urlstring];
    NSMutableURLRequest *request=[NSMutableURLRequest requestWithURL:url];
    [request addValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
    [request setHTTPMethod:@"POST"];
    [request setHTTPBody:[poststr dataUsingEncoding:NSUTF8StringEncoding]];
    NSOperationQueue *queue=[[NSOperationQueue alloc] init];
    [NSURLConnection sendAsynchronousRequest:request queue:queue
                           completionHandler:^(NSURLResponse *respone,
                                               NSData *data,
                                               NSError *error)
     {
         if ([data length]>0 && error==nil) {
             NSString *jsonstring=[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
             NSLog(jsonstring);
         }
     }
     ];
}