利用asi上传图片

   //利用asi上传图片

     //将图片信息转变为data

    NSData *data=UIImagePNGRepresentation([UIImage imageNamed:@"返回键.png"]);

    

    NSString *url = @"http://XXXX";

    ASIFormDataRequest *request = [ASIFormDataRequest requestWithURL: [NSURL URLWithString: url]];

    request.requestMethod=@"POST";

    

    [request addRequestHeader:@"token" value:@"XXXXXXXXXX"];

    

    

    //添加数据的格式

    [request setData:data withFileName:@"返回键.png" andContentType:@"image/png" forKey:@"avatar"];

    

    [request startSynchronous];

    NSLog(@"responseString = %@", request.responseString);