摘要：字符串長度截取，替換全部清除空格清除左空格右空格判斷是否以某個字符串開頭判斷是否以某個字符串結束轉義標簽時間日期格式轉換日一二三四五六判斷是否為數字類型設置值獲取值加入收藏夾加入收藏失敗，請使用進行添加設為首頁該操作被瀏覽器拒絕，如

字符串長度截取

function cutstr(str, len) {
    var temp,
        icount = 0,
        patrn = /[^x00-xff]/，
        strre = "";
    for (var i = 0; i < str.length; i++) {
        if (icount < len - 1) {
            temp = str.substr(i, 1);
                if (patrn.exec(temp) == null) {
                   icount = icount + 1
            } else {
                icount = icount + 2
            }
            strre += temp
            } else {
            break;
        }
    }
    return strre + "..."
}

替換全部

String.prototype.replaceAll = function(s1, s2) {
    return this.replace(new RegExp(s1, "gm"), s2)
}

清除空格

String.prototype.trim = function() {
    var reExtraSpace = /^s*(.*?)s+$/;
    return this.replace(reExtraSpace, "$1")
}

清除左空格/右空格

function ltrim(s){ return s.replace( /^(s*|　*)/, ""); }
function rtrim(s){ return s.replace( /(s*|　*)$/, ""); }

判斷是否以某個字符串開頭

String.prototype.startWith = function (s) {
    return this.indexOf(s) == 0
}

判斷是否以某個字符串結束

String.prototype.endWith = function (s) {
    var d = this.length - s.length;
    return (d >= 0 && this.lastIndexOf(s) == d)
}

轉義html標簽

function HtmlEncode(text) {
    return text.replace(/&/g, "&").replace(/"/g, """).replace(//g, ">")
}

時間日期格式轉換

Date.prototype.Format = function(formatStr) {
    var str = formatStr;
    var Week = ["日", "一", "二", "三", "四", "五", "六"];
    str = str.replace(/yyyy|YYYY/, this.getFullYear());
    str = str.replace(/yy|YY/, (this.getYear() % 100) > 9 ? (this.getYear() % 100).toString() : "0" + (this.getYear() % 100));
    str = str.replace(/MM/, (this.getMonth() + 1) > 9 ? (this.getMonth() + 1).toString() : "0" + (this.getMonth() + 1));
    str = str.replace(/M/g, (this.getMonth() + 1));
    str = str.replace(/w|W/g, Week[this.getDay()]);
    str = str.replace(/dd|DD/, this.getDate() > 9 ? this.getDate().toString() : "0" + this.getDate());
    str = str.replace(/d|D/g, this.getDate());
    str = str.replace(/hh|HH/, this.getHours() > 9 ? this.getHours().toString() : "0" + this.getHours());
    str = str.replace(/h|H/g, this.getHours());
    str = str.replace(/mm/, this.getMinutes() > 9 ? this.getMinutes().toString() : "0" + this.getMinutes());
    str = str.replace(/m/g, this.getMinutes());
    str = str.replace(/ss|SS/, this.getSeconds() > 9 ? this.getSeconds().toString() : "0" + this.getSeconds());
    str = str.replace(/s|S/g, this.getSeconds());
    return str
}

判斷是否為數字類型

function isDigit(value) {
    var patrn = /^[0-9]*$/;
    if (patrn.exec(value) == null || value == "") {
        return false
    } else {
        return true
    }
}

設置cookie值

function setCookie(name, value, Hours) {
    var d = new Date();
    var offset = 8;
    var utc = d.getTime() + (d.getTimezoneOffset() * 60000);
    var nd = utc + (3600000 * offset);
    var exp = new Date(nd);
    exp.setTime(exp.getTime() + Hours * 60 * 60 * 1000);
    document.cookie = name + "=" + escape(value) + ";path=/;expires=" + exp.toGMTString() + ";domain=360doc.com;"
}

獲取cookie值

function getCookie(name) {
    var arr = document.cookie.match(new RegExp("(^| )" + name + "=([^;]*)(;|$)"));
    if (arr != null) return unescape(arr[2]);
    return null
}

加入收藏夾

function AddFavorite(sURL, sTitle) {
    try {
        window.external.addFavorite(sURL, sTitle)
    } catch(e) {
        try {
            window.sidebar.addPanel(sTitle, sURL, "")
        } catch(e) {
            alert("加入收藏失敗，請使用Ctrl+D進行添加")
        }
    }
}

設為首頁

function setHomepage() {
    if (document.all) {
        document.body.style.behavior = "url(#default#homepage)";
        document.body.setHomePage("http://w3cboy.com")
    } else if (window.sidebar) {
        if (window.netscape) {
            try {
                netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect")
            } catch(e) {
                alert("該操作被瀏覽器拒絕，如果想啟用該功能，請在地址欄內輸入 about:config,然后將項 signed.applets.codebase_principal_support 值該為true")
                }
        }
        var prefs = Components.classes["@mozilla.org/preferences-service;1"].getService(Components.interfaces.nsIPrefBranch);
        prefs.setCharPref("browser.startup.homepage", "http://w3cboy.com")
    }
}

加載樣式文件

function LoadStyle(url) {
    try {
        document.createStyleSheet(url)
    } catch(e) {
        var cssLink = document.createElement("link");
        cssLink.rel = "stylesheet";
        cssLink.type = "text/css";
        cssLink.href = url;
        var head = document.getElementsByTagName("head")[0];
        head.appendChild(cssLink)
    }
}

返回腳本內容

function evalscript(s) {
    if(s.indexOf("]*?>([^x00]*?)/ig;
    var arr = [];
    while(arr = p.exec(s)) {
        var p1 = /]*?src="([^>]*?)"[^>]*?(reload="1")?(?:charset="([w-]+?)")?>/i;
        var arr1 = [];
        arr1 = p1.exec(arr[0]);
        if(arr1) {
            appendscript(arr1[1], "", arr1[2], arr1[3]);
        } else {
            p1 = /([^x00]+?)/i;
            arr1 = p1.exec(arr[0]);
            appendscript("", arr1[2], arr1[1].indexOf("reload=") != -1);
        }
    }
    return s;
}

清除腳本內容

function stripscript(s) {
    return s.replace(/.*?/ig, "");
}

動態加載腳本文件

function appendscript(src, text, reload, charset) {
    var id = hash(src + text);
    if(!reload && in_array(id, evalscripts)) return;
    if(reload && $(id)) {
        $(id).parentNode.removeChild($(id));
    }

    evalscripts.push(id);
    var scriptNode = document.createElement("script");
    scriptNode.type = "text/javascript";
    scriptNode.id = id;
    scriptNode.charset = charset ? charset : (BROWSER.firefox ? document.characterSet : document.charset);
    try {
        if(src) {
            scriptNode.src = src;
            scriptNode.onloadDone = false;
            scriptNode.onload = function () {
                scriptNode.onloadDone = true;
                JSLOADED[src] = 1;
             };
             scriptNode.onreadystatechange = function () {
                 if((scriptNode.readyState == "loaded" || scriptNode.readyState == "complete") && !scriptNode.onloadDone) {
                    scriptNode.onloadDone = true;
                    JSLOADED[src] = 1;
                }
             };
        } else if(text){
            scriptNode.text = text;
        }
        document.getElementsByTagName("head")[0].appendChild(scriptNode);
    } catch(e) {}
}

返回按ID檢索的元素對象

function $(id) {
    return !id ? null : document.getElementById(id);
}

跨瀏覽器綁定事件

function addEventSamp(obj,evt,fn){
    if(!oTarget){return;}
    if (obj.addEventListener) {
        obj.addEventListener(evt, fn, false);
    }else if(obj.attachEvent){
        obj.attachEvent("on"+evt,fn);
    }else{
        oTarget["on" + sEvtType] = fn;
    }
}

跨瀏覽器刪除事件

function delEvt(obj,evt,fn){
    if(!obj){return;}
    if(obj.addEventListener){
        obj.addEventListener(evt,fn,false);
    }else if(oTarget.attachEvent){
        obj.attachEvent("on" + evt,fn);
    }else{
        obj["on" + evt] = fn;
    }
}