总结一些javascript经典函数：
为了节约版面，也为了加快下载速度，有些函数写在了一行，读者可以粘出来仔细查看，我认为比较好的几个函数，与大家共勉。
1、获取字符串长度
function getStringLength(str)...{
var endvalue=0; var sourcestr=new String(str); var tempstr;
for (var strposition = 0; strposition < sourcestr.length; strposition ++) ...{ tempstr=sourcestr.charAt(strposition); if (tempstr.charCodeAt(0)>255 || tempstr.charCodeAt(0)<0) ...{ endvalue=endvalue+2; } else ...{ endvalue=endvalue+1;
} } return(endvalue);
}
2、去除字符串两端空格
function Trim(s){var m = s.match(/^/s*(/S+(/s+/S+)*)/s*$/);return (m == null)?"":m[1];}
3、将字符串进行U编码与解码
function StrCode(str)...{if(encodeURIComponent) return encodeURIComponent(str);if(escape) return escape(str);}function UnStrCode(str)...{if(decodeURIComponent ) return decodeURIComponent (str);if(unescape) return unescape(str);}4、将字符串进行HtmlEncode与HtmlDecode操作
function HtmlEncode(text)...{var re = ...{'<':'<','>':'>','&':'&','"':'"'};for (i in re) text = text.replace(new RegExp(i,'g'), re[i]);return text;}function HtmlDecode(text)...{var re = ...{'<':'<','>':'>','&':'&','"':'"'};for (i in re) text = text.replace(new RegExp(i,'g'), re[i]);return text;}5、获取对象 （主要解决多种浏览器兼容问题）
function GetId(id)...{return document.getElementById?document.getElementById(id):null;}function GetName(id)...{return document.getElementsByName?document.getElementsByName(id):null;}function GetNames(name)...{return document.getElementsByTagName?document.getElementsByTagName(name):new Array()}6、检查游览器 （isIE,isNS）
function Browser()...{var ua, s, i;this.isIE = false;this.isNS = false;this.isOP = false;this.isSF = false;ua = navigator.userAgent.toLowerCase();s = "opera";if ((i = ua.indexOf(s)) >= 0)...{this.isOP = true;return;}s = "msie";if ((i = ua.indexOf(s)) >= 0) ...{this.isIE = true;return;}s = "netscape6/";if ((i = ua.indexOf(s)) >= 0) ...{this.isNS = true;return;}s = "gecko";if ((i = ua.indexOf(s)) >= 0) ...{this.isNS = true;return;}s = "safari";if ((i = ua.indexOf(s)) >= 0) ...{this.isSF = true;return;}}7、ajax异步数据访问
function InitRequest()...{var C_req = null;try...{C_req = new ActiveXObject("Msxml2.XMLHTTP");}catch(e)...{try...{C_req = new ActiveXObject("Microsoft.XMLHTTP");}catch(oc)...{C_req = null;}}if (!C_req && typeof XMLHttpRequest != "undefined")...{try...{C_req = new XMLHttpRequest();}catch(fa)...{alert("对不起!您的浏览器不支持该功能,请使用Internet Explorer 6.0或FireFox浏览器!");C_req = null;}}return C_req;}function PostRequest(url, data)...{var AjaxRequestObj = InitRequest();if (AjaxRequestObj != null)...{AjaxRequestObj.onreadystatechange = function ()...{if (AjaxRequestObj.readyState == 4 && AjaxRequestObj.responseText)...{ProcessAjaxData(AjaxRequestObj.responseText);}};AjaxRequestObj.open("POST", url, true);AjaxRequestObj.setRequestHeader("Content-Type","application/x-www-form-urlencoded");AjaxRequestObj.send(data);}}function ProcessAjaxData(data)...{eval(data);} 8、用层显示一个弹出窗口
注：页面上需要有<div id="ScreenOver"></div><div id="DialogMove"></div>
function ScreenConvert()...{var browser = new Browser();var objScreen = GetId("ScreenOver");if(!objScreen) var objScreen = document.createElement("div");var oS = objScreen.style;objScreen.id = "ScreenOver";oS.display = "block";oS.top = oS.left = oS.margin = oS.padding = "0px";if (document.body.clientHeight) ...{var wh = document.body.clientHeight + "px";}else if (window.innerHeight)...{var wh = window.innerHeight + "px";}else...{var wh = "100%";}oS.width = "100%";oS.height = wh;oS.position = "absolute";oS.zIndex = "3";if ((!browser.isSF) && (!browser.isOP))...{oS.background = "#cccccc";}else...{oS.background = "#cccccc";}oS.filter = "alpha(opacity=40)";oS.opacity = 40/100;oS.MozOpacity = 40/100;document.body.appendChild(objScreen);var allselect = GetNames("select");for (var i=0; i<allselect.length; i++) allselect[i].style.visibility = "hidden";}function ScreenClean()...{var objScreen = GetId("ScreenOver");if (objScreen) objScreen.style.display = "none";var allselect = GetNames("select");for (var i=0; i<allselect.length; i++) allselect[i].style.visibility = "visible";}var t_DiglogX,t_DiglogY,t_DiglogW,t_DiglogH;function DialogLoc()...{var dde = document.documentElement;if (window.innerWidth)...{var ww = window.innerWidth;var wh = window.innerHeight;var bgX = window.pageXOffset;var bgY = window.pageYOffset;}else...{var ww = dde.offsetWidth;var wh = dde.offsetHeight;var bgX = dde.scrollLeft;var bgY = dde.scrollTop;}t_DiglogX = (bgX + ((ww - t_DiglogW)/2));t_DiglogY = (bgY + ((wh - t_DiglogH)/2));}function DialogShow(showdata,ow,oh,w,h)...{var objDialog = GetId("DialogMove");if (!objDialog) objDialog = document.createElement("div");t_DiglogW = ow;t_DiglogH = oh;DialogLoc();objDialog.id = "DialogMove";var oS = objDialog.style;oS.display = "block";oS.top = t_DiglogY + "px";oS.left = t_DiglogX + "px";oS.margin = "0px";oS.padding = "0px";oS.width = w + "px";oS.height = h + "px";oS.position = "absolute";oS.zIndex = "5";oS.background = "#FFF