Ajax 之【文件上传】

// 前台

var formData = new FormData();
    var file = document.getElementById('myFile').files[0];
    formData.append('myFile', file);

    var xhr = new XMLHttpRequest();

    xhr.open('post', '/upload', true);

    xhr.upload.onprogress = function(e) {
      if (e.lengthComputable) {
        var percentage = (e.loaded / e.total) * 100;
        $('div.progress div.bar').css('width', percentage + '%');
      }
    };

    xhr.onerror = function(e) {
      showInfo('An error occurred while submitting the form. Maybe your file is too big');
    };

    xhr.onload = function() {
      showInfo(this.statusText);
        $('#message').val(window.location.origin + "/" + xhr.responseText.replace("\\","/"));
    };

    xhr.send(formData);

//后端
var express = require('express'),
 app.use(express.bodyParser({
    keepExtensions: true,
    uploadDir: __dirname + web_upload_directory,
    limit: 1024MB
  }));

app.post('/', function(req, res) {
    colog.info(Timestamp() + "File uploaded: " + req.files.myFile.path);
    var filepath = req.files.myFile.path;
    res.send(filepath.replace(web_upload_rootpath,""));
  res.end();
});