我正在尝试使用 AJAX 通过表单发送一些值(数据),但 req.body 始终为空或值未定义

I am trying to send some values (data) by form using AJAX but req.body is always empty or value undefined

我正在尝试使用 AJAX 通过表单发送一些值(数据),但 req.body 始终为空或值未定义。

app.post('/add', urlencodedParser, function(req, res) {  
    console.log(req.body.email1);
    console.log(req.body.name1);
    console.log(req.body);
    //res.render(req.body.message);
    res.redirect('/todo');
});

尝试使用 json 解析器而不是 urlencoded 解析器。

var bodyParser = require('body-parser');

app.post('/add', bodyParser.json(), function (req, res) {
    console.log(req.body.email1);
    console.log(req.body.name1);
    console.log(req.body);
    //res.render(req.body.message);
    res.redirect('/todo');
});

您可能通过 AJAX 调用发送了 JSON 数据,这就是 urlencoded 解析器无法解析正文的原因。更多信息:https://www.quora.com/What-exactly-does-body-parser-do-with-express-js-and-why-do-I-need-it

更新

当您将 post 数据作为 multipart/form-data 发送时,您将需要 multernode.js

中解析此数据
var multer = require('multer')
var upload = multer();

app.post('/add', upload.array(), function (req, res) {
    console.log(req.body);
});

使用req.param('email1')代替req.body

//这在客户端...

<script>
        $(document.forms['formName']).on('submit', function(){
            var form = $(this);
            $.ajax({
                url: "/add",
                method: "POST",
                data: form.serialize(),
                statusCode: {
                    200: function(){
                        window.location.href = "/todo"
                    },
                    400: function(jqXHR){
                       //display errors
                    }
                }
            });
            return false;
        });
    </script>

//在服务器端

app.post('/add', function (req, res, next) {
    console.log(req.body.email1);
    console.log(req.body.name1);
    console.log(req.body);
    res.status(200);
});

在您需要连接之前

app.use(bodyParser.urlencoded({
    extended: true
}));
app.use(bodyParser.json());

希望对您有所帮助

如果需要,表单视图

<form name = "formName">
    <fieldset class="form-group">
        <label for="email1">Enter email</label>
        <input type="text" class="form-control" name = "email1" id="email1" placeholder = "Enter email">
    </fieldset>

    <fieldset class="form-group">
        <label for="name1">Enter name</label>
        <input type="text" class="form-control" name="name1" id="name1" placeholder="Enter name">
    </fieldset>

    <button type="submit" class="btn btn-primary">Send</button>
</form>