XMLHttpRequest.response - Web APIs 编辑

The XMLHttpRequest response property returns the response's body content as an ArrayBuffer, Blob, Document, JavaScript Object, or DOMString, depending on the value of the request's responseType property.

Syntax

var body = XMLHttpRequest.response;

Value

An appropriate object based on the value of responseType. You may attempt to request the data be provided in a specific format by setting the value of responseType after calling open() to initialize the request but before calling send() to send the request to the server.

The value is null if the request is not yet complete or was unsuccessful, with the exception that when reading text data using a responseType of "text" or the empty string (""), the response can contain the response so far while the request is still in the LOADING readyState (3).

The response types are described below.

""

An empty responseType string is treated the same as "text", the default type.

arraybuffer

The response is a JavaScript ArrayBuffer containing binary data.

blob

The response is a Blob object containing the binary data.

document

The response is an HTML Document or XML XMLDocument, as appropriate based on the MIME type of the received data. See HTML in XMLHttpRequest to learn more about using XHR to fetch HTML content.

json

The response is a JavaScript object created by parsing the contents of received data as JSON.

text

The response is a text in a DOMString object.

ms-stream

The response is part of a streaming download; this response type is only allowed for download requests, and is only supported by Internet Explorer.

Example

This example presents a function, load(), which loads and processes a page from the server. It works by creating an XMLHttpRequest object and creating a listener for readystatechange events such that when readyState changes to DONE (4), the response is obtained and passed into the callback function provided to load().

The content is handled as raw text data (since nothing here is overriding the default responseType).

var url = 'somePage.html'; //A local page

function load(url, callback) {
  var xhr = new XMLHttpRequest();

  xhr.onreadystatechange = function() {
    if (xhr.readyState === 4) {
      callback(xhr.response);
    }
  }

  xhr.open('GET', url, true);
  xhr.send('');
}

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• Using XMLHttpRequest
• Getting text and HTML/XML data: XMLHttpRequest.responseText and XMLHttpRequest.responseXML