iOS微信支付简单的使用

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Override point for customization after application launch.
    

    [WXApi registerApp:@"填写你的微信APPID" withDescription:@"weixinDemo"];
    
    
    return YES;
}

/*! @brief 发送一个sendReq后，收到微信的回应
 *
 * 收到一个来自微信的处理结果。调用一次sendReq后会收到onResp。
 * 可能收到的处理结果有SendMessageToWXResp、SendAuthResp等。
 * @param resp具体的回应内容，是自动释放的
 */
-(void)onResp:(BaseResp *)resp
{
    if ([resp isKindOfClass:[PayResp class]])
    {
        //返回支付结果,实际支付结果需要取微信服务端查询
        NSString *strMsg = @"支付结果";
        switch (resp.errCode) {
            case WXSuccess:
                strMsg = @"支付成功";
                NSLog(@"支付成功-PaySuccess,resp.errCode = %d",resp.errCode);
                break;
                
            default:
                strMsg = @"支付失败";
                NSLog(@"支付失败-PaySuccess,resp.errCode = %d,resp.errStr = %@",resp. errCode,resp.errStr);
                break;
        }
        
        UIAlertController *alertController = [UIAlertController alertControllerWithTitle:[NSString stringWithFormat:@"%d",resp.errCode ]message:resp.errStr preferredStyle:UIAlertControllerStyleAlert];
        UIAlertAction *sure = [UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleDefault handler:^(UIAlertAction * _Nonnull action) {
            
        }];
        [alertController addAction:sure];
        [self.window.rootViewController presentViewController:alertController animated:YES completion:^{
            
        }];
    }
}

#pragma mark - 跳转到微信应用（第三方）
-(BOOL)application:(UIApplication *)app openURL:(NSURL *)url options:(NSDictionary<NSString *,id> *)options
{
    // 处理微信通过URL启动App时传递的数据
    return [WXApi handleOpenURL:url delegate:self];
}

+ (NSString *)jumpToBizPay {

    if (![WXApi isWXAppInstalled]) {
        NSLog(@"该设备没有安装微信");
        return @"该设备没有安装微信";
    }
    
    if (![WXApi isWXAppSupportApi]) {
        NSLog(@"该设备不支持微信");
        return @"该设备不支持微信";
    }
    
    //============================================================
    // V3&V4支付流程实现
    // 注意:参数配置请查看服务器端Demo
    // 更新时间：2015年11月20日
    //============================================================
    NSString *urlString   = @"http://wxpay.weixin.qq.com/pub_v2/app/app_pay.php?plat=ios";
    //解析服务端返回json数据
    NSError *error;
    //加载一个NSURL对象
    NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:urlString]];
    //将请求的url数据放到NSData对象中
    NSData *response = [NSURLConnection sendSynchronousRequest:request returningResponse:nil error:nil];
    if ( response != nil) {
        NSMutableDictionary *dict = NULL;
        //IOS5自带解析类NSJSONSerialization从response中解析出数据放到字典中
        dict = [NSJSONSerialization JSONObjectWithData:response options:NSJSONReadingMutableLeaves error:&error];
        
        NSLog(@"url:%@",urlString);
        if(dict != nil){
            NSMutableString *retcode = [dict objectForKey:@"retcode"];
            if (retcode.intValue == 0){
                NSMutableString *stamp  = [dict objectForKey:@"timestamp"];
                
                //调起微信支付
                PayReq* req             = [[PayReq alloc] init];
                req.partnerId           = [dict objectForKey:@"partnerid"];
                req.prepayId            = [dict objectForKey:@"prepayid"];
                req.nonceStr            = [dict objectForKey:@"noncestr"];
                req.timeStamp           = stamp.intValue;
                req.package             = [dict objectForKey:@"package"];
                req.sign                = [dict objectForKey:@"sign"];
                [WXApi sendReq:req];
                //日志输出
                NSLog(@"appid=%@\npartid=%@\nprepayid=%@\nnoncestr=%@\ntimestamp=%ld\npackage=%@\nsign=%@",[dict objectForKey:@"appid"],req.partnerId,req.prepayId,req.nonceStr,(long)req.timeStamp,req.package,req.sign );
                return @"";
            }else{
                return [dict objectForKey:@"retmsg"];
            }
        }else{
            return @"服务器返回错误，未获取到json对象";
        }
    }else{
        return @"服务器返回错误";
    }
}