怎样使用FormData对象加工表单数据

1. 获取表单(form)节点

2. 对FormData实例做相关操作

3. 发起HTTP请求

function sendForm(form) {

  var formData = new FormData(form);

  formData.append('csrf', 'e69a18d7db1286040586e6da1950128c');

  var xhr = new XMLHttpRequest();

  xhr.open('POST', form.action, true);

  xhr.onload = function() {

    // ...

  };

  xhr.send(formData);

  return false;

}

var form = document.querySelector('#registration');

sendForm(form);