转自 攻城狮-JavaScript 经常运用要领总结

手机范例推断

var BrowserInfo = {
    userAgent: navigator.userAgent.toLowerCase()
    isAndroid: Boolean(navigator.userAgent.match(/android/ig)),
    isIphone: Boolean(navigator.userAgent.match(/iphone|ipod/ig)),
    isIpad: Boolean(navigator.userAgent.match(/ipad/ig)),
    isWeixin: Boolean(navigator.userAgent.match(/MicroMessenger/ig)),
}

返回字符串长度，汉字计数为2

function strLength(str) {
    var a = 0;
    for (var i = 0; i < str.length; i++) {
        if (str.charCodeAt(i) > 255)
            a += 2;//依据预期计数增添2
        else
            a++;
    }
    return a;
}


猎取url中的参数 


function GetQueryStringRegExp(name,url) {
    var reg = new RegExp("(^|\\?|&)" + name + "=([^&]*)(\\s|&|$)", "i");
    if (reg.test(url)) return decodeURIComponent(RegExp.$2.replace(/\+/g, " ")); return "";
}
　　

js 绑定事宜 适用于任何浏览器的元素绑定

function eventBind(obj, eventType, callBack) {
        if (obj.addEventListener) {
            obj.addEventListener(eventType, callBack, false);
        }
        else if (window.attachEvent) {
            obj.attachEvent('on' + eventType, callBack);
        }
        else {
            obj['on' + eventType] = callBack;
        }
    };
eventBind(document, 'click', bodyClick);
　　

取得当前浏览器JS的版本

function getjsversion(){
    var n = navigator;
    var u = n.userAgent;
    var apn = n.appName;
    var v = n.appVersion;
    var ie = v.indexOf('MSIE ');
    if (ie > 0){
        apv = parseInt(i = v.substring(ie + 5));
        if (apv > 3) {
            apv = parseFloat(i);
        }
    } else {
        apv = parseFloat(v);
    }
    var isie = (apn == 'Microsoft Internet Explorer');
    var ismac = (u.indexOf('Mac') >= 0);
    var javascriptVersion = "1.0";
    if (String && String.prototype) {
        javascriptVersion = '1.1';
        if (javascriptVersion.match) {
            javascriptVersion = '1.2';
            var tm = new Date;
            if (tm.setUTCDate) {
                javascriptVersion = '1.3';
                if (isie && ismac && apv >= 5) javascriptVersion = '1.4';
                var pn = 0;
                if (pn.toPrecision) {
                    javascriptVersion = '1.5';
                    a = new Array;
                    if (a.forEach) {
                        javascriptVersion = '1.6';
                        i = 0;
                        o = new Object;
                        tcf = new Function('o', 'var e,i=0;try{i=new Iterator(o)}catch(e){}return i');
                        i = tcf(o);
                        if (i && i.next) {
                            javascriptVersion = '1.7';
                        }
                    }
                }
            }
        }
    }
    return javascriptVersion;
}
　　

猎取当前点击事宜的Object对象

function getEvent() {
    if (document.all) {
        return window.event; //如果是ie
    }
    func = getEvent.caller;
    while (func != null) {
        var arg0 = func.arguments[0];
        if (arg0) {
            if ((arg0.constructor == Event || arg0.constructor == MouseEvent)
|| (typeof (arg0) == "object" && arg0.preventDefault && arg0.stopPropagation)) {
                return arg0;
            }
        }
        func = func.caller;
    }
    return null;
};
　　

字符串截取要领

getCharactersLen: function (charStr, cutCount) {
        if (charStr == null || charStr == '') return '';
        var totalCount = 0;
        var newStr = '';
        for (var i = 0; i < charStr.length; i++) {
            var c = charStr.charCodeAt(i);
            if (c < 255 && c > 0) {
                totalCount++;
            } else {
                totalCount += 2;
            }
            if (totalCount >= cutCount) {
                newStr += charStr.charAt(i);
                break;
            }
            else {
                newStr += charStr.charAt(i);
            }
        }
        return newStr;
    }
　　

JS 弹出新窗口全屏

var tmp = window.open("about:blank", "", "fullscreen=1")
                            tmp.moveTo(0, 0);
                            tmp.resizeTo(screen.width + 20, screen.height);
                            tmp.focus();
                            tmp.location.href = 'http://www.che168.com/pinggu/eva_' + msgResult.message[0] + '.html';

var config_ = "left=0,top=0,width=" + (window.screen.Width) + ",height=" + (window.screen.Height);
                            window.open('http://www.che168.com/pinggu/eva_' + msgResult.message[0] + '.html', "winHanle", config_);
//模仿form提交翻开新页面
var f = document.createElement("form");
                            f.setAttribute('action', 'http://www.che168.com/pinggu/eva_' + msgResult.message[0] + '.html');
                            f.target = '_blank';
                            document.body.appendChild(f);
                            f.submit();
　　

全选/全不选

function selectAll(objSelect) {
            if (objSelect.checked == true) {
                $("input[name='chkId']").attr("checked", true);
                $("input[name='chkAll']").attr("checked", true);
            }
            else if (objSelect.checked == false) {
                $("input[name='chkId']").attr("checked", false);
                $("input[name='chkAll']").attr("checked", false);
            }
        }
　　

js 推断浏览器

推断是不是是 IE 浏览器
    if (document.all){
        alert(”IE浏览器”);
    }else{
        alert(”非IE浏览器”);
    }
    if (!!window.ActiveXObject){
        alert(”IE浏览器”);
    }else{
        alert(”非IE浏览器”);
    }
推断是IE几
var isIE=!!window.ActiveXObject;
var isIE6=isIE&&!window.XMLHttpRequest;
var isIE8=isIE&&!!document.documentMode;
var isIE7=isIE&&!isIE6&&!isIE8;
if (isIE){
    if (isIE6){
        alert(”ie6″);
    }else if (isIE8){
        alert(”ie8″);
    }else if (isIE7){
        alert(”ie7″);
    }
}
　　

推断浏览器

function getOs() {
    if (navigator.userAgent.indexOf("MSIE 8.0") > 0) {
        return "MSIE8";
    }
    else if (navigator.userAgent.indexOf("MSIE 6.0") > 0) {
        return "MSIE6";
    }
    else if (navigator.userAgent.indexOf("MSIE 7.0") > 0) {
        return "MSIE7";
    }
    else if (isFirefox = navigator.userAgent.indexOf("Firefox") > 0) {
        return "Firefox";
    }
    if (navigator.userAgent.indexOf("Chrome") > 0) {
        return "Chrome";
    }
    else {
        return "Other";
    }
}
　　

JS推断两个日期大小 合适 2012-09-09 与2012-9-9 两种花样的对照

11
12
13
//获得日期值并转化成日期花样，replace(/\-/g, "\/")是依据考证表达式把日期转化生长日期花样，如许再举行推断就好推断了
        function ValidateDate() {
            var beginDate = $("#t_datestart").val();
            var endDate = $("#t_dateend").val();
            if (beginDate.length > 0 && endDate.length>0) {
                var sDate = new Date(beginDate.replace(/\-/g, "\/"));
                var eDate= new Date(endDate.replace(/\-/g, "\/"));
                if (sDate > eDate) {
                    alert('最先日期要小于完毕日期');
                    return false;
                }
            }
        }
　　

移除事宜

this.moveBind = function (objId, eventType, callBack) {
    var obj = document.getElementById(objId);
    if (obj.removeEventListener) {
        obj.removeEventListener(eventType, callBack, false);
    }
    else if (window.detachEvent) {
        obj.detachEvent('on' + eventType, callBack);
    }
    else {
        obj['on' + eventType] = null;
    }
}
　　

回车提交

$("id").onkeypress = function (event) {
    event = (event) ? event : ((window.event) ? window.event : "")
    keyCode = event.keyCode ? event.keyCode : (event.which ? event.which : event.charCode);
    if (keyCode == 13) {
        $("SubmitLogin").onclick();
    }
}
　　

JS 实行计时器

timeStart = new Date().getTime();
timesEnd = new Date().getTime();
document.getElementById("time").innerHTML = timesEnd - timeStart;
　　

JS 写Cookie

function setCookie(name, value, expires, path, domain) {
    if (!expires) expires = -1;
    if (!path) path = "/";
    var d = "" + name + "=" + value;
    var e;
    if (expires < 0) {
        e = "";
    }
    else if (expires == 0) {
        var f = new Date(1970, 1, 1);
        e = ";expires=" + f.toUTCString();
    }
    else {
        var now = new Date();
        var f = new Date(now.getTime() + expires * 1000);
        e = ";expires=" + f.toUTCString();
    }
    var dm;
    if (!domain) {
        dm = "";
    }
    else {
        dm = ";domain=" + domain;
    }
    document.cookie = name + "=" + value + ";path=" + path + e + dm;
};
　　

JS 读Cookie

function readCookie(name) {
    var nameEQ = name + "=";
    var ca = document.cookie.split(';');
    for (var i = 0; i < ca.length; i++) {
        var c = ca[i];
        while (c.charAt(0) == ' ') c = c.substring(1, c.length);
        if (c.indexOf(nameEQ) == 0) {
            return decodeURIComponent(c.substring(nameEQ.length, c.length))
        }
    } return null
}
　　

Ajax 要求

C.ajax = function (args) {
    var self = this;
    this.options = {
        type: 'GET',
        async: true,
        contentType: 'application/x-www-form-urlencoded',
        url: 'about:blank',
        data: null,
        success: {},
        error: {}
    };
    this.getXmlHttp = function () {
        var xmlHttp;
        try {
            xmlhttp = new XMLHttpRequest();
        }
        catch (e) {
            try {
                xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
            }
            catch (e) {
                xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
            }
        }
        if (!xmlhttp) {
            alert('您的浏览器不支持AJAX');
            return false;
        }
        return xmlhttp;
    };
    this.send = function () {
        C.each(self.options, function (key, val) {
            self.options[key] = (args[key] == null) ? val : args[key];
        });

        var xmlHttp = new self.getXmlHttp();
        if (self.options.type.toUpperCase() == 'GET') {
            xmlHttp.open(self.options.type, self.options.url + (self.options.data == null ? "" : ((/[?]$/.test(self.options.url) ? '&' : '?') + self.options.data)), self.options.async);
        }
        else {
            xmlHttp.open(self.options.type, self.options.url, self.options.async);
            xmlHttp.setRequestHeader('Content-Length', self.options.data.length);
        }
        xmlHttp.setRequestHeader('Content-Type', self.options.contentType);
        xmlHttp.onreadystatechange = function () {
            if (xmlHttp.readyState == 4) {
                if (xmlHttp.status == 200 || xmlHttp.status == 0) {
                    if (typeof self.options.success == 'function') self.options.success(xmlHttp.responseText);
                    xmlHttp = null;
                }
                else {
                    if (typeof self.options.error == 'function') self.options.error('Server Status: ' + xmlHttp.status);
                }
            }
        };

        xmlHttp.send(self.options.type.toUpperCase() == 'POST' ? self.options.data.toString() : null);
    };
    this.send();
};
　　

JS StringBuilder 用法

function StringBuilder() {
    this.strings = new Array;
};
StringBuilder.prototype.append = function (str) {
    this.strings.push(str);
};
StringBuilder.prototype.toString = function () {
    return this.strings.join('');
};
　　

JS 加载到顶部LoadJS

function loadJS (url, fn) {
        var ss = document.getElementsByName('script'),
            loaded = false;
        for (var i = 0, len = ss.length; i < len; i++) {
            if (ss[i].src && ss[i].getAttribute('src') == url) {
                loaded = true;
                break;
            }
        }
        if (loaded) {
            if (fn && typeof fn != 'undefined' && fn instanceof Function) fn();
            return false;
        }
        var s = document.createElement('script'),
            b = false;
        s.setAttribute('type', 'text/javascript');
        s.setAttribute('src', url);
        s.onload = s.onreadystatechange = function () {
            if (!b && (!this.readyState || this.readyState == 'loaded' || this.readyState == 'complete')) {
                b = true;
                if (fn && typeof fn != 'undefined' && fn instanceof Function) fn();
            }
        };
        document.getElementsByTagName('head')[0].appendChild(s);
    },
    bind: function (objId, eventType, callBack) {  //适用于任何浏览器的绑定
        var obj = document.getElementById(objId);
        if (obj.addEventListener) {
            obj.addEventListener(eventType, callBack, false);
        }
        else if (window.attachEvent) {
            obj.attachEvent('on' + eventType, callBack);
        }
        else {
            obj['on' + eventType] = callBack;
        }
    }

function JSLoad (args) {
        s = document.createElement("script");
        s.setAttribute("type", "text/javascript");
        s.setAttribute("src", args.url);
        s.onload = s.onreadystatechange = function () {
            if (!s.readyState || s.readyState == "loaded" || s.readyState == "complete") {
                if (typeof args.callback == "function") args.callback(this, args);
                s.onload = s.onreadystatechange = null;
                try {
                    s.parentNode && s.parentNode.removeChild(s);
                } catch (e) { }
            }
        };
        document.getElementsByTagName("head")[0].appendChild(s);
    }
　　

清空 LoadJS 加载到顶部的js援用

function ClearHeadJs  (src) {
        var js = document.getElementsByTagName('head')[0].children;
        var obj = null;
        for (var i = 0; i < js.length; i++) {
            if (js[i].tagName.toLowerCase() == "script" && js[i].attributes['src'].value.indexOf(src) > 0) {
                obj = js[i];
            }
        }
        document.getElementsByTagName('head')[0].removeChild(obj);
    };
　　

JS 替代不法字符重要用在暗码考证上涌现的特别字符

function URLencode(sStr) {
    return escape(sStr).replace(/\+/g, '%2B').replace(/\"/g, '%22').replace(/\'/g, '%27').replace(/\//g, '%2F');
};
　　

按Ctrl + Entert 直接提交表单

document.body.onkeydown = function (evt) {
    evt = evt ? evt : (window.event ? window.event : null);
    if (13 == evt.keyCode && evt.ctrlKey) {
        evt.returnValue = false;
        evt.cancel = true;
        PostData();
    }
};
　　

猎取当前时候

function GetCurrentDate() {
        var d = new Date();
        var y = d.getYear()+1900;
        month = add_zero(d.getMonth() + 1),
        days = add_zero(d.getDate()),
        hours = add_zero(d.getHours());
        minutes = add_zero(d.getMinutes()),
        seconds = add_zero(d.getSeconds());
        var str = y + '-' + month + '-' + days + ' ' + hours + ':' + minutes + ':' + seconds;
        return str;
    };
    function add_zero(temp) {
        if (temp < 10) return "0" + temp;
        else return temp;
    }
　　

Js 去掉空格要领：

String.prototype.Trim = function()
{ return this.replace(/(^\s*)|(\s*$)/g, ""); }
String.prototype.LTrim = function()
{return this.replace(/(^\s*)/g, "");}
String.prototype.RTrim = function()
{return this.replace(/(\s*$)/g, "");}
　　

js 动态移除 head 里的 js 援用

this.ClearHeadJs = function (src) {
    var js = document.getElementsByTagName('head')[0].children;
    var obj = null;
    for (var i = 0; i < js.length; i++) {
        if (js[i].tagName.toLowerCase() == "script" && js[i].attributes['src'].value.indexOf(src) > 0) {
            obj = js[i];
        }
    }
    document.getElementsByTagName('head')[0].removeChild(obj);
};
　　

全部UL 点击事宜 加在UL里的onclick里

function CreateFrom(url, params) {
     var f = document.createElement("form");
     f.setAttribute("action", url);
     for (var i = 0; i < params.length; i++) {
         var input = document.createElement("input");
         input.setAttribute("type", "hidden");
         input.setAttribute("name", params[i].paramName);
         input.setAttribute("value", params[i].paramValue);
         f.appendChild(input);
     }
     f.target = "_blank";
     document.body.appendChild(f);
     f.submit();
 };
　　

推断浏览器运用的是哪一个 JS 版本

<script language="javascript">
      var jsversion = 1.0;
    </script>


    <script language="javascript1.1">
      jsversion = 1.1;
    </script>
    <script language="javascript1.2">
      jsversion = 1.2;
    </script>
    <script language="javascript1.3">
      jsversion = 1.3;
    </script>
    <script language="javascript1.4">
      jsversion = 1.4;
    </script>
    <script language="javascript1.5">
      jsversion = 1.5;
    </script>
    <script language="javascript1.6">
      jsversion = 1.6;
    </script>
    <script language="javascript1.7">
      jsversion = 1.7;
    </script>
    <script language="javascript1.8">
      jsversion = 1.8;
    </script>
    <script language="javascript1.9">
      jsversion = 1.9;
    </script>
    <script language="javascript2.0">
      jsversion = 2.0;
    </script>
alert(jsversion);