如何在目标c中使用JSON服务发布数据

Question

我已经制作了登录表单。字段R电子邮件和密码。现在，我想将数据从字段发布到特定URL如何完成。我是iOS的新手。有谁能够帮助我？？如何进行HTTP请求和JSON解析？

Answer 1

/*********See this**********/
-(void)webServiceCall{
NSString *dataToSend = [NSString stringWithFormat:@"Username=%@&Password=%@“,<userIdEnter Here>,<Password enter here>]; 
NSData *postData = [post dataUsingEncoding:NSASCIIStringEncoding allowLossyConversion:YES]; 
NSMutableURLRequest *request = [[NSMutableURLRequest alloc] init]; 
NSString *Length = [NSString stringWithFormat:@"%d",[postData length]]; 
[request setURL:[NSURL URLWithString:@“WEBURL”]]; 
[request setHTTPMethod:@"POST"]; 
[request setValue:Length forHTTPHeaderField:@"Content-Length"]; 
[request setValue:@"application/x-www-form-urlencoded" forHTTPHeaderField:@"Content-Type"];
[request setHTTPBody:postData];
NSURLConnection *conn = [[NSURLConnection alloc] initWithRequest:request delegate:self]; 

 }
// check connection if you want
/*****get response in delegates*******/

 - (void)connection:(NSURLConnection *)connection didReceiveResponse:
  (NSURLResponse *)response {
    // A response has been received, this is where we initialize the instance var you created
    // so that we can append data to it in the didReceiveData method
    // Furthermore, this method is called each time there is a redirect so reinitializing it
    // also serves to clear it
    _responseData = [[NSMutableData alloc] init];
      }
    - (void)connection:(NSURLConnection *)connection didReceiveData:(NSData*)data
    {
         /**************/
  NSString* newStr = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];

    NSError* error;
    NSDictionary* json = [NSJSONSerialization JSONObjectWithData:data
                                                         options:kNilOptions
                                                           error:&error];
   // NSArray* latestLoans = [json objectForKey:@"loans"];
    NSLog(@"json: %@", json);
    [_responseData appendData:data];

    }
    - (void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error 
    {
 NSLog(@"Error --> %@",error.localizedDescription);
        /***************/
    }
    - (void)connectionDidFinishLoading:(NSURLConnection *)connection
    {
 NSString *responseString = [[NSString alloc] initWithData:self.responseData encoding:NSUTF8StringEncoding];
 NSError *error = nil;
        id result = [NSJSONSerialization JSONObjectWithData:jsonData options:NSJSONReadingMutableContainers error:&error];
// use Result
self.responseData = nil;
    }