NSURLConnection获取数据

- (void)loadDataFromUrl

{

    NSURL* url = [NSURL URLWithString:@"http://m.weather.com.cn/data/101190408.html"];

    NSMutableURLRequest * urlRequest=[NSMutableURLRequest requestWithURL:url];

    NSURLConnection* urlConn = [[NSURLConnection alloc] initWithRequest:urlRequest delegate:self];

    [urlConn start];

}



- (void)connection:(NSURLConnection *)connection didReceiveResponse:(NSURLResponse*)response

{

    NSHTTPURLResponse* rsp = (NSHTTPURLResponse*)response;

    int code = [rsp statusCode];

    if (code != 200)

    {

        [connection cancel];

        [connection release];

        connection = nil;

    }

    else

    {

        if (mData != nil)

        {

            [mData release];

            mData = nil;

        }

        mData = [[NSMutableData alloc] init];

    }

}



- (void)connection:(NSURLConnection *)connection didReceiveData:(NSData *)data

{

    [mData appendData:data];

}



- (void)connectionDidFinishLoading:(NSURLConnection *)connection

{

   // [self hideAlert];

    NSString* backString = [[NSMutableString alloc] initWithData:mData encoding:NSUTF8StringEncoding];

    NSMutableDictionary *backData  =[backString JSONValue];

    NSLog(@"%@",backData);

    connection = nil;

}



-(void)connection:(NSURLConnection *)connection didFailWithError:(NSError *)error

{

    [connection release];

    connection = nil;

}



-(void)showAlertView:(NSString*)titleStr

{

    UIAlertView *myalert = [[UIAlertView alloc]

                            initWithTitle:@"提示"

                            message:titleStr

                            delegate:self

                            cancelButtonTitle:@"取消"

                            otherButtonTitles:nil];

    [myalert show];

    [myalert release];

}