如果url中直接有中文，而不做任何處理的話，不會解析，返回為空。需要轉(zhuǎn)碼。

// 將中文URL進行轉(zhuǎn)碼
    urlStr = [urlStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

GET

- (void)get
{
    // 0.請求路徑
    NSString *urlStr = @"http://120.25.226.186:32812/login2?username=小碼哥&pwd=520it";
    // 將中文URL進行轉(zhuǎn)碼
    urlStr = [urlStr stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];
    NSURL *url = [NSURL URLWithString:urlStr];
    
    // 1.創(chuàng)建請求對象
    NSURLRequest *request = [NSURLRequest requestWithURL:url];
    
    // 2.發(fā)送請求
    [NSURLConnection sendAsynchronousRequest:request queue:[[NSOperationQueue alloc] init] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
        // 3.解析服務(wù)器返回的數(shù)據(jù)（解析成字符串）
        NSString *string = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
        NSLog(@"%@", string);
    }];
}

POST

- (void)post
{
    // 0.請求路徑
    NSString *urlStr = @"http://120.25.226.186:32812/login2";
    NSURL *url = [NSURL URLWithString:urlStr];
    
    // 1.創(chuàng)建請求對象
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:url];
    request.HTTPMethod = @"POST";
    request.HTTPBody = [@"username=小碼哥&pwd=520it" dataUsingEncoding:NSUTF8StringEncoding];
    
    // 2.發(fā)送請求
    [NSURLConnection sendAsynchronousRequest:request queue:[[NSOperationQueue alloc] init] completionHandler:^(NSURLResponse *response, NSData *data, NSError *connectionError) {
        // 3.解析服務(wù)器返回的數(shù)據(jù)（解析成字符串）
        NSString *string = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
        NSLog(@"%@", string);
    }];
}