Ajax浏览器分辨利器xmlhttprequest
2007/1/15 21:31:35
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我们在应用Ajax技术的时候经常会因为多种浏览器不兼容的原因而发愁，现在有了Cross-Browser XMLHttpRequest v1.2，xmlHttpRequest请求及浏览器分辨的事情再也不需要我们去烦心了。 整个文件的代码内容如下： /* Cross-Browser XMLHttpRequest v1.2================================= Emulate Gecko 'XMLHttpRequest()' functionality in IE and Opera. Opera requiresthe Sun Java Runtime Environment <http://www.java.com/>. by Andrew Gregoryhttp://www.scss.com.au/family/andrew/webdesign/xmlhttprequest/ This work is licensed under the Creative Commons Attribution License. To view acopy of this license, visit http://creativecommons.org/licenses/by-sa/2.5/ orsend a letter to Creative Commons, 559 Nathan Abbott Way, Stanford, California94305, 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 supportif (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 supportif (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 emulationif (!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; };}
Posted by Qr on 2007/1/15 21:31:35
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