From: http://www.scss.com.au/family/andrew/webdesign/xmlhttprequest/
/*
Cross-Browser XMLHttpRequest v1.2
=================================
Emulate Gecko 'XMLHttpRequest()' functionality in IE and Opera. Opera requires
the Sun Java Runtime Environment <http://www.java.com/>.
by Andrew Gregory
http://www.scss.com.au/family/andrew/webdesign/xmlhttprequest/
This work is licensed under the Creative Commons Attribution License. To view a
copy of this license, visit http://creativecommons.org/licenses/by-sa/2.5/ or
send a letter to Creative Commons, 559 Nathan Abbott Way, Stanford, California
94305, USA.
Attribution: Leave my name and web address in this script intact.
Not Supported in Opera
----------------------
* user/password authentication
* responseXML data member
Not Fully Supported in Opera
----------------------------
* async requests
* abort()
* getAllResponseHeaders(), getAllResponseHeader(header)
*/
// IE support
if (window.ActiveXObject && !window.XMLHttpRequest) {
? window.XMLHttpRequest = function() {
??? var msxmls = new Array(
????? 'Msxml2.XMLHTTP.5.0',
????? 'Msxml2.XMLHTTP.4.0',
????? 'Msxml2.XMLHTTP.3.0',
????? 'Msxml2.XMLHTTP',
????? 'Microsoft.XMLHTTP');
??? for (var i = 0; i < msxmls.length; i++) {
????? try {
??????? return new ActiveXObject(msxmls[i]);
????? } catch (e) {
????? }
??? }
??? return null;
? };
}
// Gecko support
/* ;-) */
// Opera support
if (window.opera && !window.XMLHttpRequest) {
? window.XMLHttpRequest = function() {
??? this.readyState = 0; // 0=uninitialized,1=loading,2=loaded,3=interactive,4=complete
??? this.status = 0; // HTTP status codes
??? this.statusText = '';
??? this._headers = [];
??? this._aborted = false;
??? this._async = true;
??? this._defaultCharset = 'ISO-8859-1';
??? this._getCharset = function() {
????? var charset = _defaultCharset;
????? var contentType = this.getResponseHeader('Content-type').toUpperCase();
????? val = contentType.indexOf('CHARSET=');
????? if (val != -1) {
??????? charset = contentType.substring(val);
????? }
????? val = charset.indexOf(';');
????? if (val != -1) {
??????? charset = charset.substring(0, val);
????? }
????? val = charset.indexOf(',');
????? if (val != -1) {
??????? charset = charset.substring(0, val);
????? }
????? return charset;
??? };
??? this.abort = function() {
????? this._aborted = true;
??? };
??? this.getAllResponseHeaders = function() {
????? return this.getAllResponseHeader('*');
??? };
??? this.getAllResponseHeader = function(header) {
????? var ret = '';
????? for (var i = 0; i < this._headers.length; i++) {
??????? if (header == '*' || this._headers[i].h == header) {
????????? ret += this._headers[i].h + ': ' + this._headers[i].v + '\n';
??????? }
????? }
????? return ret;
??? };
??? this.getResponseHeader = function(header) {
????? var ret = getAllResponseHeader(header);
????? var i = ret.indexOf('\n');
????? if (i != -1) {
??????? ret = ret.substring(0, i);
????? }
????? return ret;
??? };
??? this.setRequestHeader = function(header, value) {
????? this._headers[this._headers.length] = {h:header, v:value};
??? };
??? this.open = function(method, url, async, user, password) {
????? this.method = method;
????? this.url = url;
????? this._async = true;
????? this._aborted = false;
????? this._headers = [];
????? if (arguments.length >= 3) {
??????? this._async = async;
????? }
????? if (arguments.length > 3) {
??????? opera.postError('XMLHttpRequest.open() - user/password not supported');
????? }
????? this.readyState = 1;
????? if (this.onreadystatechange) {
??????? this.onreadystatechange();
????? }
??? };
??? this.send = function(data) {
????? if (!navigator.javaEnabled()) {
??????? alert("XMLHttpRequest.send() - Java must be installed and enabled.");
??????? return;
????? }
????? if (this._async) {
??????? setTimeout(this._sendasync, 0, this, data);
??????? // this is not really asynchronous and won't execute until the current
??????? // execution context ends
????? } else {
??????? this._sendsync(data);
????? }
??? }
??? this._sendasync = function(req, data) {
????? if (!req._aborted) {
??????? req._sendsync(data);
????? }
??? };
??? this._sendsync = function(data) {
????? this.readyState = 2;
????? if (this.onreadystatechange) {
??????? this.onreadystatechange();
????? }
????? // open connection
????? var url = new java.net.URL(new java.net.URL(window.location.href), this.url);
????? var conn = url.openConnection();
????? for (var i = 0; i < this._headers.length; i++) {
??????? conn.setRequestProperty(this._headers[i].h, this._headers[i].v);
????? }
????? this._headers = [];
????? if (this.method == 'POST') {
??????? // POST data
??????? conn.setDoOutput(true);
??????? var wr = new java.io.OutputStreamWriter(conn.getOutputStream(), this._getCharset());
??????? wr.write(data);
??????? wr.flush();
??????? wr.close();
????? }
????? // read response headers
????? // NOTE: the getHeaderField() methods always return nulls for me :(
????? var gotContentEncoding = false;
????? var gotContentLength = false;
????? var gotContentType = false;
????? var gotDate = false;
????? var gotExpiration = false;
????? var gotLastModified = false;
????? for (var i = 0; ; i++) {
??????? var hdrName = conn.getHeaderFieldKey(i);
??????? var hdrValue = conn.getHeaderField(i);
??????? if (hdrName == null && hdrValue == null) {
????????? break;
??????? }
??????? if (hdrName != null) {
????????? this._headers[this._headers.length] = {h:hdrName, v:hdrValue};
????????? switch (hdrName.toLowerCase()) {
??????????? case 'content-encoding': gotContentEncoding = true; break;
??????????? case 'content-length'? : gotContentLength?? = true; break;
??????????? case 'content-type'??? : gotContentType???? = true; break;
??????????? case 'date'??????????? : gotDate??????????? = true; break;
??????????? case 'expires'???????? : gotExpiration????? = true; break;
??????????? case 'last-modified'?? : gotLastModified??? = true; break;
????????? }
??????? }
????? }
????? // try to fill in any missing header information
????? var val;
????? val = conn.getContentEncoding();
????? if (val != null && !gotContentEncoding) this._headers[this._headers.length] = {h:'Content-encoding', v:val};
????? val = conn.getContentLength();
????? if (val != -1 && !gotContentLength) this._headers[this._headers.length] = {h:'Content-length', v:val};
????? val = conn.getContentType();
????? if (val != null && !gotContentType) this._headers[this._headers.length] = {h:'Content-type', v:val};
????? val = conn.getDate();
????? if (val != 0 && !gotDate) this._headers[this._headers.length] = {h:'Date', v:(new Date(val)).toUTCString()};
????? val = conn.getExpiration();
????? if (val != 0 && !gotExpiration) this._headers[this._headers.length] = {h:'Expires', v:(new Date(val)).toUTCString()};
????? val = conn.getLastModified();
????? if (val != 0 && !gotLastModified) this._headers[this._headers.length] = {h:'Last-modified', v:(new Date(val)).toUTCString()};
????? // read response data
????? var reqdata = '';
????? var stream = conn.getInputStream();
????? if (stream) {
??????? var reader = new java.io.BufferedReader(new java.io.InputStreamReader(stream, this._getCharset()));
??????? var line;
??????? while ((line = reader.readLine()) != null) {
????????? if (this.readyState == 2) {
??????????? this.readyState = 3;
??????????? if (this.onreadystatechange) {
????????????? this.onreadystatechange();
??????????? }
????????? }
????????? reqdata += line + '\n';
??????? }
??????? reader.close();
??????? this.status = 200;
??????? this.statusText = 'OK';
??????? this.responseText = reqdata;
??????? this.readyState = 4;
??????? if (this.onreadystatechange) {
????????? this.onreadystatechange();
??????? }
??????? if (this.onload) {
????????? this.onload();
??????? }
????? } else {
??????? // error
??????? this.status = 404;
??????? this.statusText = 'Not Found';
??????? this.responseText = '';
??????? this.readyState = 4;
??????? if (this.onreadystatechange) {
????????? this.onreadystatechange();
??????? }
??????? if (this.onerror) {
????????? this.onerror();
??????? }
????? }
??? };
? };
}
// ActiveXObject emulation
if (!window.ActiveXObject && window.XMLHttpRequest) {
? window.ActiveXObject = function(type) {
??? switch (type.toLowerCase()) {
????? case 'microsoft.xmlhttp':
????? case 'msxml2.xmlhttp':
????? case 'msxml2.xmlhttp.3.0':
????? case 'msxml2.xmlhttp.4.0':
????? case 'msxml2.xmlhttp.5.0':
??????? return new XMLHttpRequest();
??? }
??? return null;
? };
}