iOS 获取外网ip地址

- (void)getIp

{

    NSLog(@"开始获取ip");

    NSError*error;

    NSString*ip =@"";

    // 方法1    不稳定，有时太慢，有时得不到结果

    NSURL *url = [NSURL URLWithString:@"https://ifconfig.me/ip"];

    ip = [NSString stringWithContentsOfURL:url encoding:NSUTF8StringEncoding error:&error];

    // 方法2

    NSURL *url = [NSURL URLWithString:@"http://ip.taobao.com/service/getIpInfo.php?ip=myip"];

    NSString *response = [NSString stringWithContentsOfURL:url encoding:NSUTF8StringEncoding error:&error];

    NSDictionary*dicResponse = [responsemj_JSONObject];

    if(dicResponse && dicResponse[@"data"]) {

        NSDictionary*dicData = dicResponse[@"data"];

        if(dicData && dicData[@"ip"]) {

            ip = dicData[@"ip"];

        }

    }

    // 方法3 

    NSURL *url = [NSURL URLWithString:@"http://pv.sohu.com/cityjson?ie=utf-8"];

    NSString*response = [NSString stringWithContentsOfURL:url encoding:NSUTF8StringEncoding error:&error];

    //判断返回字符串是否为所需数据

    NSString *prefix = @"var returnCitySN = ";

    if([responsehasPrefix:prefix]) {

        // 删除多余内容

        response = [responsesubstringFromIndex:prefix.length];

        response = [responsesubstringToIndex:response.length-1];

        NSDictionary*dicResponse = [responsemj_JSONObject];

        if(dicResponse && dicResponse[@"cip"]) {

            ip = dicResponse[@"cip"];

        }

    }

    NSLog(@"当前网络ip %@", ip);

}