ios_http_json Ojb-c 请求网页数据 ( Http请求)

// 判断服务器后台广告开关是否打开
// 服务器返回的数据格式如下：
[{"pid":"120005","id":0,"is_open":"0"}]

-(BOOL)AdIsOpen
{
    BOOL retIsOpen = false;

    NSString* postUrl=@"";
    NSString* strPid =@"110005";
    NSString* strDownPid =@"120005"; // 下传数据的 pid
    NSString* strId =@"1"; // 服务器后台分配的配置 id


    NSMutableDictionary *postDict = [[NSMutableDictionary alloc] init];

    // 设置 post 提交的数据
    [postDict setObject:@"110005" forKey:@"pid"];
    [postDict setObject:@"1" forKey:@"id"];


    NSString *jsonStr = [self sendRequestTo:[NSURL URLWithString:postUrl] usingVerb:@"POST" withParameters:postDict];
    NSLog(@" verify_server repost= %@", jsonStr);

    NSDictionary *retDict = [jsonStr JSONValue];
    //NSLog(@"do post: retDict = %@， %@", retDict, [retDict description]);

    //得到词典中所有Value值
    NSEnumerator * enumeratorValue = [retDict objectEnumerator];

    //快速枚举遍历所有Value的值
    for (NSObject *object in enumeratorValue)
    {
        //NSLog(@"遍历Value的值: %@",object);

        if([object isKindOfClass:[NSDictionary class]])
        {
            NSDictionary* dict = (NSDictionary*)object;


            // 当前的协议数据 pid = 120005
            if( [[dict objectForKey:@"pid"] isEqualToString:strDownPid] && // 广告开关数据
                 [[dict objectForKey:@"is_open"] intValue]==1)
            {
                retIsOpen = true;
                NSLog(@"AdIsOpen :true");
            }
        }
    }

    [postDict release];
    postDict = nil;

    return retIsOpen;

}


/**
 * url:请求地址
 * verb:请求方式, 默认传递 @"POST" 就可以
 * parameters:请求参数
 */
-(NSString *)sendRequestTo:(NSURL *)url usingVerb:(NSString *)verb withParameters:(NSDictionary *)parameters
{
    NSString *jsonStr = nil;
    NSData *body = nil;
    NSMutableString *params = nil;
    NSString *contentType = @"text/html; charset=utf-8";
    NSURL *finalURL = url;
    if(nil != parameters){
        params = [[NSMutableString alloc] init];
        for(id key in parameters){
            NSString *encodedkey = [key stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

            CFStringRef value = (__bridge CFStringRef)[[parameters objectForKey:key] copy];
            CFStringRef encodedValue = CFURLCreateStringByAddingPercentEscapes(kCFAllocatorDefault, value,NULL,(CFStringRef)@";/?:@&=+$", kCFStringEncodingUTF8);
            [params appendFormat:@"%@=%@&", encodedkey, encodedValue];
            CFRelease(value);
            CFRelease(encodedValue);
        }
        [params deleteCharactersInRange:NSMakeRange([params length] - 1, 1)];
    }
    //
    if([verb isEqualToString:@"POST"]){
        contentType = @"application/x-www-form-urlencoded; charset=utf-8";
        body = [params dataUsingEncoding:NSUTF8StringEncoding];
    }else{
        if(nil != parameters){
            NSString *urlWithParams = [[url absoluteString] stringByAppendingFormat:@"?%@", params];
            finalURL = [NSURL URLWithString:urlWithParams];
        }
    }
    NSMutableDictionary *headers = [[NSMutableDictionary alloc] init];
    [headers setValue:contentType forKey:@"Content-Type"];
    [headers setValue:@"text/html" forKey:@"Accept"];
    [headers setValue:@"no-cache" forKey:@"Cache-Control"];
    [headers setValue:@"no-cache" forKey:@"Pragma"];
    [headers setValue:@"close" forKey:@"Connection"];
    NSMutableURLRequest *request = [NSMutableURLRequest requestWithURL:finalURL cachePolicy:NSURLRequestUseProtocolCachePolicy timeoutInterval:60.0];
    [request setHTTPMethod:verb];
    [request setAllHTTPHeaderFields:headers];
    if(nil != parameters){
        [request setHTTPBody:body];
    }
    params = nil;
    //
    NSURLResponse *response;
    NSError *error = nil;
    NSData *responseData = [NSURLConnection sendSynchronousRequest:request returningResponse:&response error:&error];
    if(error){
        NSLog(@"something is wrong: %@", [error description]);
    }else{
        if(responseData){
            jsonStr = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];
        }
    }
    return  jsonStr;
}