Question

以下是我的代码，我首先验证用户是否存在于组中，如果存在，则将帐户推入阵列并保存。这是通过/ addaccount上的POST请求完成的。

groupRouter.post('/addaccount', Verify.verifyOrdinaryUser, function(req, res, next) {
Groups.findById(req.body.group, function(err,group) {
    if (err) next(err);
    var checkUser = function(user) {
        for(var i=0; i<group.users.length; i++)
        {
            if(group.users[i]==user)
                return true;
        }
        return false;
    }
    if(checkUser(req.decoded._doc._id)){
        User.find({mobile:{$in:req.body.split}}, function(err, users) {
            if(err) next(err); var flag = true;
            if(users.length == req.body.split.length ) {
                for(var i=0; i<users.length; i++) {
                    if(!checkUser(''+users[i]._id)) {
                        flag = false;
                        break;
                    }
                }
                if(flag) {
                    var myObject = {};
                    myObject.amount = req.body.amount;
                    myObject.by = req.decoded._doc._id;
                    myObject.split = req.body.split;
                    group.accounts.push(myObject);
                    group.save(function (err, groups) {
                        if(err) next(err);
                        console.log('Added entries');
                        res.json(groups);
                    })
                }
                else
                    res.end('All users not in the group');
            }
            else
                res.end('Split users do not exist');
        })
    }
    else
        res.end('No Permission');
})
})

现在当我输入一个用户数组并尝试推送一个对象并通过代码如下：

if(flag) {
                var myObject = {};
                myObject.amount = req.body.amount;
                myObject.by = req.decoded._doc._id;
                myObject.split = req.body.split;
                group.accounts.push(myObject);
                group.save(function (err, groups) {
                    if(err) next(err);
                    console.log('Added entries');
                    res.json(groups);
                })
            }

我收到错误消息：错误：发送后无法设置标头。如下图所示。

Error: Can't set headers after they are sent.
at ServerResponse.OutgoingMessage.setHeader (_http_outgoing.js:357:11)
at ServerResponse.header (D:\Ionic\PocketBuddies\node_modules\express\lib\response.js:718:10)
at ServerResponse.send (D:\Ionic\PocketBuddies\node_modules\express\lib\response.js:163:12)
at done (D:\Ionic\PocketBuddies\node_modules\express\lib\response.js:957:10)
at Object.exports.renderFile (D:\Ionic\PocketBuddies\node_modules\jade\lib\index.js:374:12)
at View.exports.__express [as engine] (D:\Ionic\PocketBuddies\node_modules\jade\lib\index.js:417:11)
at View.render (D:\Ionic\PocketBuddies\node_modules\express\lib\view.js:126:8)
at tryRender (D:\Ionic\PocketBuddies\node_modules\express\lib\application.js:639:10)
at EventEmitter.render (D:\Ionic\PocketBuddies\node_modules\express\lib\application.js:591:3)
at ServerResponse.render (D:\Ionic\PocketBuddies\node_modules\express\lib\response.js:961:7)
at D:\Ionic\PocketBuddies\app.js:78:7
at Layer.handle_error (D:\Ionic\PocketBuddies\node_modules\express\lib\router\layer.js:71:5)
at trim_prefix (D:\Ionic\PocketBuddies\node_modules\express\lib\router\index.js:310:13)
at D:\Ionic\PocketBuddies\node_modules\express\lib\router\index.js:280:7
at Function.process_params (D:\Ionic\PocketBuddies\node_modules\express\lib\router\index.js:330:12)
at IncomingMessage.next (D:\Ionic\PocketBuddies\node_modules\express\lib\router\index.js:271:10)

我搜索了这个问题，它说我无法在res.end（）之后更新响应，但是当我调用res.json时，我没有看到任何res.end（）被调用。请帮我在这里找到一个问题。我正在研究一个项目，这个错误让我发疯。

提前致谢

Answer 1

正如robertklep正确指出的那样，这里的问题是没有返回错误，因此在group.save（）函数发生错误后它会呈现错误页面并且它会点击res.json （）导致错误。如果没有错误，它可以正常工作。代码需要按如下方式更新，以便在错误发生时返回错误，而不是转移到res.json（）部分。

group.save(function (err, groups) {
                    if(err) return next(err);
                    console.log('Added entries');
                    res.json(groups);
                })

通过向我提供实际错误，然后在事情正常工作后必须纠正错误，这对我来说是个窍门。

发送后无法设置标头。的NodeJS

1 个答案: