[Summary view] [Print] [Text view]

   1  /*

   2  Copyright (c) 2003-2010, CKSource - Frederico Knabben. All rights reserved.

   3  For licensing, see LICENSE.html or http://ckeditor.com/license

   4  */
   5  
   6  /**

   7   * @fileOverview Defines the {@link CKEDITOR.ajax} object, which holds ajax methods for

   8   *        data loading.

   9   */
  10  
  11  /**

  12   * Ajax methods for data loading.

  13   * @namespace

  14   * @example

  15   */
  16  CKEDITOR.ajax = (function()
  17  {
  18      var createXMLHttpRequest = function()
  19      {
  20          // In IE, using the native XMLHttpRequest for local files may throw

  21          // "Access is Denied" errors.

  22          if ( !CKEDITOR.env.ie || location.protocol != 'file:' )
  23              try { return new XMLHttpRequest(); } catch(e) {}
  24  
  25          try { return new ActiveXObject( 'Msxml2.XMLHTTP' ); } catch (e) {}
  26          try { return new ActiveXObject( 'Microsoft.XMLHTTP' ); } catch (e) {}
  27  
  28          return null;
  29      };
  30  
  31      var checkStatus = function( xhr )
  32      {
  33          // HTTP Status Codes:

  34          //     2xx : Success

  35          //     304 : Not Modified

  36          //       0 : Returned when running locally (file://)

  37          //    1223 : IE may change 204 to 1223 (see http://dev.jquery.com/ticket/1450)

  38  
  39          return ( xhr.readyState == 4 &&
  40                  (    ( xhr.status >= 200 && xhr.status < 300 ) ||
  41                      xhr.status == 304 ||
  42                      xhr.status === 0 ||
  43                      xhr.status == 1223 ) );
  44      };
  45  
  46      var getResponseText = function( xhr )
  47      {
  48          if ( checkStatus( xhr ) )
  49              return xhr.responseText;
  50          return null;
  51      };
  52  
  53      var getResponseXml = function( xhr )
  54      {
  55          if ( checkStatus( xhr ) )
  56          {
  57              var xml = xhr.responseXML;
  58              return new CKEDITOR.xml( xml && xml.firstChild ? xml : xhr.responseText );
  59          }
  60          return null;
  61      };
  62  
  63      var load = function( url, callback, getResponseFn )
  64      {
  65          var async = !!callback;
  66  
  67          var xhr = createXMLHttpRequest();
  68  
  69          if ( !xhr )
  70              return null;
  71  
  72          xhr.open( 'GET', url, async );
  73  
  74          if ( async )
  75          {
  76              // TODO: perform leak checks on this closure.

  77              /** @ignore */

  78              xhr.onreadystatechange = function()
  79              {
  80                  if ( xhr.readyState == 4 )
  81                  {
  82                      callback( getResponseFn( xhr ) );
  83                      xhr = null;
  84                  }
  85              };
  86          }
  87  
  88          xhr.send(null);
  89  
  90          return async ? '' : getResponseFn( xhr );
  91      };
  92  
  93      return     /** @lends CKEDITOR.ajax */ {
  94  
  95          /**

  96           * Loads data from an URL as plain text.

  97           * @param {String} url The URL from which load data.

  98           * @param {Function} [callback] A callback function to be called on

  99           *        data load. If not provided, the data will be loaded

 100           *        asynchronously, passing the data value the function on load.

 101           * @returns {String} The loaded data. For asynchronous requests, an

 102           *        empty string. For invalid requests, null.

 103           * @example

 104           * // Load data synchronously.

 105           * var data = CKEDITOR.ajax.load( 'somedata.txt' );

 106           * alert( data );

 107           * @example

 108           * // Load data asynchronously.

 109           * var data = CKEDITOR.ajax.load( 'somedata.txt', function( data )

 110           *     {

 111           *         alert( data );

 112           *     } );

 113           */
 114          load : function( url, callback )
 115          {
 116              return load( url, callback, getResponseText );
 117          },
 118  
 119          /**

 120           * Loads data from an URL as XML.

 121           * @param {String} url The URL from which load data.

 122           * @param {Function} [callback] A callback function to be called on

 123           *        data load. If not provided, the data will be loaded

 124           *        asynchronously, passing the data value the function on load.

 125           * @returns {CKEDITOR.xml} An XML object holding the loaded data. For asynchronous requests, an

 126           *        empty string. For invalid requests, null.

 127           * @example

 128           * // Load XML synchronously.

 129           * var xml = CKEDITOR.ajax.loadXml( 'somedata.xml' );

 130           * alert( xml.getInnerXml( '//' ) );

 131           * @example

 132           * // Load XML asynchronously.

 133           * var data = CKEDITOR.ajax.loadXml( 'somedata.xml', function( xml )

 134           *     {

 135           *         alert( xml.getInnerXml( '//' ) );

 136           *     } );

 137           */
 138          loadXml : function( url, callback )
 139          {
 140              return load( url, callback, getResponseXml );
 141          }
 142      };
 143  })();