我在客户端的执行代码： wx.login({     success: function (result) {         if (result.code) {             wx.request({                 url: config.service.requestUrl + '/v.php',                 data: {                     code: result.code                 },                 header: {                     'content-type': 'application/x-www-form-urlencoded'                 },                 method: 'POST',                 success: function (res) {                     wx.getUserInfo({                         success: function (res) {                             that.localData.rawdata = res.rawData                             that.localData.signature = res.signature                             that.globalData.userInfo = res.userInfo                             wx.request({                                 url: config.service.requestUrl + '/verify.php',                                 data: {},                                 header: {                                     'content-type': 'application/x-www-form-urlencoded',                                     'Cookie': 'PHPSESSID=' + wx.getStorageSync('session_id'),                                     'raw': escape(this.localData.rawdata),                                     'signature': this.localData.signature                                 },                                 method: 'POST',                                 success: function (res) {                                 },                                 fail: function (res) {                                 }                             })                         }                     })                 }             })         }     } }) 在v.php中，通过appid、appsecret、code获取到了openid和session_key，并保存到开发者服务器。 在verify.php中：         $raw = js_unescape ($_SERVER['HTTP_RAW']);         $sig = $_SERVER['HTTP_SIGNATURE'];         $cleartext = $raw . $session_key;         $signature = sha1($cleartext); 现在，问题来了：$sig和$signature，这两个值在某些情况下是相同的，而在某些情况下是不同的！我们用了很多个手机做测试，相同和不同的概率大概五五开，而且跟IOS系统或Android系统无关。咋回事呢？