Question

我在尝试从我们公司需要身份验证的网站上获取JSON页面时遇到问题。

- http://xyz.com - 要求身份验证
- 我需要从http://xyz.com/jsonpage1获取数据 - 在View DidLoad中，我发送用户和密码登录以建立会话
- 然后，我有一个请求JSON的按钮。

此序列不起作用（意味着如果会话加载代码与json加载代码的例程不同）。如果我在相同的例程中有两个代码，如视图didLoad，那么它似乎识别我的凭据并获得JSON。奇怪！我错过了什么？该怎么办？我认为建立会话会创建一次cookie而不需要再打扰它？当我点击按钮时，我是否会以某种方式丢失cookie？

-(void)viewDidLoad
{
  [self establishSession];
}

-(void)establishSession{   
//
//Login Session
//
NSURL *url = [NSURL URLWithString:@"http://xyz.com/login"];
NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];

NSString *post = [NSString stringWithFormat:@"username=%@&password=%@",@"abc",@"123"];
NSData *postData = [post dataUsingEncoding:NSUTF8StringEncoding allowLossyConversion:YES];

[request setValue:[NSString stringWithFormat:@"%d",[postData length]] forHTTPHeaderField:@"Content-Length"];
[request setTimeoutInterval:15];
[request setHTTPBody:postData];
[request setHTTPMethod:@"POST"];

urlConnection = [[NSURLConnection alloc] initWithRequest:request delegate:self];
[urlConnection start];

}

- (IBAction)getJSON:(id)sender
{
 NSError *error = nil;

resultsView.text =@"";

[self establishLoginSession];   //I have to have this line here to get it to work ?????

//get JSON

NSURL *jurl = [NSURL URLWithString:@"http://xyz.com/jsonPage1"];

NSData *jdata = [NSData dataWithContentsOfURL:jurl options:NSDataReadingUncached error:&error];
NSDictionary* jsonDict = [NSJSONSerialization
                      JSONObjectWithData:jdata //1
                      options:kNilOptions
                      error:&error];

NSString *dataString = [[NSString alloc]initWithData:jdata encoding:NSUTF8StringEncoding];
resultsView.text = dataString;
}

//Not sure if I need the cookie??
-(void) connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse  *)response
{

NSHTTPURLResponse *HTTPResponse = (NSHTTPURLResponse*) response;
NSDictionary *fields = [HTTPResponse allHeaderFields];

if([fields valueForKey:@"Set-Cookie"])
   cookie = [fields valueForKey:@"Set-Cookie"];

}

Answer 1

您只能使用NSURLConnection对象发出一个请求，因此您应该在发出请求之前创建它。

如何使用NSURLRequest的cookie从WEBserver获取JSON数据？

1 个答案: