FormData

Thu, Nov 21, 2019

typedef (File or USVString) FormDataEntryValue;

[Exposed=(Window,Worker)]
interface FormData {
  constructor(optional HTMLFormElement form);

  void append(USVString name, USVString value);
  void append(USVString name, Blob blobValue, optional USVString filename);
  void delete(USVString name);
  FormDataEntryValue? get(USVString name);
  sequence<FormDataEntryValue> getAll(USVString name);
  boolean has(USVString name);
  void set(USVString name, USVString value);
  void set(USVString name, Blob blobValue, optional USVString filename);
  iterable<USVString, FormDataEntryValue>;
};

FormData	类型	说明
has(name)	boolean
get(name)	FormDataEntryValue
getAll(name)	sequence<FormDataEntryValue>
append(name,value)	void
append(name,blobValue,filename)	void
set(name)	void
set(name,blobValue,filename)	void
delete(name)	void

FormData构造函数

语法: 
var formData = new FormData(form)
form(可选):
一个HTML 上的<form>表单元素——当指定了，这种方式创建的FormData对象会自动将form中的表单值也包含进去，包括文件内容也会被编码之后包含进去。

利用FormData提交表单

<form id="myForm" name="myForm">
  <div>
    <label for="username">Enter name:</label>
    <input type="text" id="username" name="username">
  </div>
  <div>
    <label for="useracc">Enter account number:</label>
    <input type="text" id="useracc" name="useracc">
  </div>
  <div>
    <label for="userfile">Upload file:</label>
    <input type="file" id="userfile" name="userfile">
  </div><input type="submit" value="Submit!"></form>
  
var myForm = document.getElementById('myForm');
formData = new FormData(myForm);