SBJsonParser *parser = [[SBJsonParser alloc] init];

    NSDictionary *rootDic = [parser objectWithString:jsonString error:&error];

    NSDictionary *weatherInfo = [rootDic objectForKey:@"weatherinfo"];

    txtView.text = [NSString stringWithFormat:@"今天是 %@  %@  %@  的天气状况是：%@  %@ ",[weatherInfo objectForKey:@"date_y"],[weatherInfo objectForKey:@"week"],[weatherInfo objectForKey:@"city"], [weatherInfo objectForKey:@"weather1"], [weatherInfo objectForKey:@"temp1"]];

}

（3）使用IOS5自带解析类NSJSONSerialization方法解析：（无需导入包，IOS5支持，低版本IOS不支持）

- (IBAction)btnPressIOS5Json:(id)sender {

    NSError *error;

    //加载一个NSURL对象

    NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:@"http://m.weather.com.cn/data/101180601.html"]];

    //将请求的url数据放到NSData对象中

    NSData *response = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];

    //IOS5自带解析类NSJSONSerialization从response中解析出数据放到字典中

    NSDictionary *weatherDic = [NSJSONSerialization JSONObjectWithData:response options:NSJSONReadingMutableLeaves error:&error];

    NSDictionary *weatherInfo = [weatherDic objectForKey:@"weatherinfo"];

    txtView.text = [NSString stringWithFormat:@"今天是 %@  %@  %@  的天气状况是：%@  %@ ",[weatherInfo objectForKey:@"date_y"],[weatherInfo objectForKey:@"week"],[weatherInfo objectForKey:@"city"], [weatherInfo objectForKey:@"weather1"], [weatherInfo objectForKey:@"temp1"]];

    NSLog(@"weatherInfo字典里面的内容为--》%@", weatherDic );

}

（4）使用JSONKit的解析方法：（需导入包：#import "JSONKit/JSONKit.h"）

- (IBAction)btnPressJsonKit:(id)sender {

    //如果json是“单层”的，即value都是字符串、数字，可以使用objectFromJSONString

    NSString *json1 = @"{\"a\":123, \"b\":\"abc\"}";

    NSLog(@"json1:%@",json1);

    NSDictionary *data1 = [json1 objectFromJSONString];

    NSLog(@"json1.a:%@",[data1 objectForKey:@"a"]);

    NSLog(@"json1.b:%@",[data1 objectForKey:@"b"]);

    [json1 release];

    //如果json有嵌套，即value里有array、object，如果再使用objectFromJSONString，程序可能会报错（测试结果表 明：使用由网络或得到的php/json_encode生成的json时会报错，但使用NSString定义的json字符串时，解析成功），最好使用 objectFromJSONStringWithParseOptions：

    NSString *json2 = @"{\"a\":123, \"b\":\"abc\", \"c\":[456, \"hello\"], \"d\":{\"name\":\"张三\", \"age\":\"32\"}}";

    NSLog(@"json2:%@", json2);