Node.js检查用户是否已经存在

您好，我正在尝试检查数据库中是否已经存在用户，如果已经存在一个具有相同名称的用户，我设法停止创建该用户，但是我似乎没有得到显示的错误消息。我不太确定为什么我的错误没有得到正确处理。这是我的代码：

 // Register User
    router.post('/register', function(req, res){
        var name = req.body.name;
        var email = req.body.email;
        var username = req.body.username;
        var password = req.body.password;
        var password2 = req.body.password2;

    //Validation
    req.checkBody('name', 'Name is required').notEmpty();
    req.checkBody('email', 'Email is required').notEmpty();
    req.checkBody('email', 'Email is not valid').isEmail();
    req.checkBody('username', 'Username is required').notEmpty();
    req.checkBody('password', 'Password is required').notEmpty();
    req.checkBody('password2', 'Passwords do not match').equals(req.body.password);

    var errors = req.validationErrors();

    if(errors){
        res.render('register',{
            errors:errors
        });
    }else{var newUser = new User({
        name: name,
        email:email,
        username: username,
        password: password
    });

    User.getUserByUsername(username, function(err, user){
        if(err) throw err;
        if(user){
            return new Error('User already exists!');
        }else{
            User.createUser(newUser, function(err, user){
                if(err) throw err;
                console.log(user);
            });
        }
    });


    req.flash('success_msg', 'You are registered and can now login');

    res.redirect('/users/login');
    }
});

这将完全按照您的意愿运行。我在尝试使其正常运行时遇到了同样的问题，我向您保证。干杯！

Node.js检查用户是否已经存在

您好，我正在尝试检查数据库中是否已经存在用户，如果已经存在一个具有相同名称的用户，我设法停止创建该用户，但是我似乎没有得到显示的错误消息。我不太确定为什么我的错误没有得到正确处理。这是我的代码：

 // Register User
    router.post('/register', function(req, res){
        var name = req.body.name;
        var email = req.body.email;
        var username = req.body.username;
        var password = req.body.password;
        var password2 = req.body.password2;

    //Validation
    req.checkBody('name', 'Name is required').notEmpty();
    req.checkBody('email', 'Email is required').notEmpty();
    req.checkBody('email', 'Email is not valid').isEmail();
    req.checkBody('username', 'Username is required').notEmpty();
    req.checkBody('password', 'Password is required').notEmpty();
    req.checkBody('password2', 'Passwords do not match').equals(req.body.password);

    var errors = req.validationErrors();

    if(errors){
        res.render('register',{
            errors:errors
        });
    }else{var newUser = new User({
        name: name,
        email:email,
        username: username,
        password: password
    });

    User.getUserByUsername(username, function(err, user){
        if(err) throw err;
        if(user){
            return new Error('User already exists!');
        }else{
            User.createUser(newUser, function(err, user){
                if(err) throw err;
                console.log(user);
            });
        }
    });


    req.flash('success_msg', 'You are registered and can now login');

    res.redirect('/users/login');
    }
});

这将完全按照您的意愿运行。我在尝试使其正常运行时遇到了同样的问题，我向您保证。干杯！