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28个常用JavaScript方法集锦

PHPz

May 16, 2016 pm 04:20 PM

javascript常用方法

本文给大家汇总介绍了28个常用的javascript方法，十分的全面，都是本人精心整理的，这里推荐给大家，有需要的小伙伴直接带走。

经常使用的 JS 方法，今天记下，以便以后查询

/* 手机类型判断 */

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，汉子计数为2 */

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

获取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 绑定事件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(&#39;on&#39; + eventType, callBack);
        }
        else {
            obj[&#39;on&#39; + eventType] = callBack;
        }
    };
eventBind(document, &#39;click&#39;, bodyClick);

/* 获得当前浏览器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(&#39;MSIE &#39;);
    if (ie > 0){
        apv = parseInt(i = v.substring(ie + 5));
        if (apv > 3) {
            apv = parseFloat(i);
        }
    } else {
        apv = parseFloat(v);
    }
    var isie = (apn == &#39;Microsoft Internet Explorer&#39;);
    var ismac = (u.indexOf(&#39;Mac&#39;) >= 0);
    var javascriptVersion = "1.0";
    if (String && String.prototype) {
        javascriptVersion = &#39;1.1&#39;;
        if (javascriptVersion.match) {
            javascriptVersion = &#39;1.2&#39;;
            var tm = new Date;
            if (tm.setUTCDate) {
                javascriptVersion = &#39;1.3&#39;;
                if (isie && ismac && apv >= 5) javascriptVersion = &#39;1.4&#39;;
                var pn = 0;
                if (pn.toPrecision) {
                    javascriptVersion = &#39;1.5&#39;;
                    a = new Array;
                    if (a.forEach) {
                        javascriptVersion = &#39;1.6&#39;;
                        i = 0;
                        o = new Object;
                        tcf = new Function(&#39;o&#39;, &#39;var e,i=0;try{i=new Iterator(o)}catch(e){}return i&#39;);
                        i = tcf(o);
                        if (i && i.next) {
                            javascriptVersion = &#39;1.7&#39;;
                        }
                    }
                }
            }
        }
    }
    return javascriptVersion;
}

/* 获取当前点击事件的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;
};

/* 字符串截取方法 */

getCharactersLen: function (charStr, cutCount) {
        if (charStr == null || charStr == &#39;&#39;) return &#39;&#39;;
        var totalCount = 0;
        var newStr = &#39;&#39;;
        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 = &#39;http://www.che168.com/pinggu/eva_&#39; + msgResult.message[0] + &#39;.html&#39;;
 
var config_ = "left=0,top=0,width=" + (window.screen.Width) + ",height=" + (window.screen.Height);
window.open(&#39;http://www.che168.com/pinggu/eva_&#39; + msgResult.message[0] + &#39;.html&#39;, "winHanle", config_);
//模拟form提交打开新页面
var f = document.createElement("form");
f.setAttribute(&#39;action&#39;, &#39;http://www.che168.com/pinggu/eva_&#39; + msgResult.message[0] + &#39;.html&#39;);
f.target = &#39;_blank&#39;;
document.body.appendChild(f);
f.submit();

/* 全选/全不选 */

function selectAll(objSelect) {
            if (objSelect.checked == true) {
                $("input[name=&#39;chkId&#39;]").attr("checked", true);
                $("input[name=&#39;chkAll&#39;]").attr("checked", true);
            }
            else if (objSelect.checked == false) {
                $("input[name=&#39;chkId&#39;]").attr("checked", false);
                $("input[name=&#39;chkAll&#39;]").attr("checked", false);
            }
        }

/* js 判断浏览器 */

判断是否是 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”);
    }

判断是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″);
    }
}

/* 判断浏览器 */

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判断两个日期大小适合 2012-09-09 与2012-9-9 两种格式的对比 */

//得到日期值并转化成日期格式，replace(/\-/g, "\/")是根据验证表达式把日期转化成长日期格式，这样再进行判断就好判断了
        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(&#39;开始日期要小于结束日期&#39;);
                    return false;
                }
            }
        }

/* 移除事件 */

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(&#39;on&#39; + eventType, callBack);
    }
    else {
        obj[&#39;on&#39; + 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 执行计时器 */

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(&#39;;&#39;);
    for (var i = 0; i < ca.length; i++) {
        var c = ca[i];
        while (c.charAt(0) == &#39; &#39;) c = c.substring(1, c.length);
        if (c.indexOf(nameEQ) == 0) {
            return decodeURIComponent(c.substring(nameEQ.length, c.length))
        }
    } return null
}

/* Ajax 请求 */

C.ajax = function (args) {
    var self = this;
    this.options = {
        type: &#39;GET&#39;,
        async: true,
        contentType: &#39;application/x-www-form-urlencoded&#39;,
        url: &#39;about:blank&#39;,
        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(&#39;您的浏览器不支持AJAX&#39;);
            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() == &#39;GET&#39;) {
            xmlHttp.open(self.options.type, self.options.url + (self.options.data == null ? "" : ((/[?]$/.test(self.options.url) ? &#39;&&#39; : &#39;?&#39;) + self.options.data)), self.options.async);
        }
        else {
            xmlHttp.open(self.options.type, self.options.url, self.options.async);
            xmlHttp.setRequestHeader(&#39;Content-Length&#39;, self.options.data.length);
        }
        xmlHttp.setRequestHeader(&#39;Content-Type&#39;, self.options.contentType);
        xmlHttp.onreadystatechange = function () {
            if (xmlHttp.readyState == 4) {
                if (xmlHttp.status == 200 || xmlHttp.status == 0) {
                    if (typeof self.options.success == &#39;function&#39;) self.options.success(xmlHttp.responseText);
                    xmlHttp = null;
                }
                else {
                    if (typeof self.options.error == &#39;function&#39;) self.options.error(&#39;Server Status: &#39; + xmlHttp.status);
                }
            }
        };
        xmlHttp.send(self.options.type.toUpperCase() == &#39;POST&#39; ? 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(&#39;&#39;);
};

/* JS 加载到顶部LoadJS */

function loadJS (url, fn) {
        var ss = document.getElementsByName(&#39;script&#39;),
            loaded = false;
        for (var i = 0, len = ss.length; i < len; i++) {
            if (ss[i].src && ss[i].getAttribute(&#39;src&#39;) == url) {
                loaded = true;
                break;
            }
        }
        if (loaded) {
            if (fn && typeof fn != &#39;undefined&#39; && fn instanceof Function) fn();
            return false;
        }
        var s = document.createElement(&#39;script&#39;),
            b = false;
        s.setAttribute(&#39;type&#39;, &#39;text/javascript&#39;);
        s.setAttribute(&#39;src&#39;, url);
        s.onload = s.onreadystatechange = function () {
            if (!b && (!this.readyState || this.readyState == &#39;loaded&#39; || this.readyState == &#39;complete&#39;)) {
                b = true;
                if (fn && typeof fn != &#39;undefined&#39; && fn instanceof Function) fn();
            }
        };
        document.getElementsByTagName(&#39;head&#39;)[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(&#39;on&#39; + eventType, callBack);
        }
        else {
            obj[&#39;on&#39; + 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引用 */

function ClearHeadJs  (src) {
        var js = document.getElementsByTagName(&#39;head&#39;)[0].children;
        var obj = null;
        for (var i = 0; i < js.length; i++) {
            if (js[i].tagName.toLowerCase() == "script" && js[i].attributes[&#39;src&#39;].value.indexOf(src) > 0) {
                obj = js[i];
            }
        }
        document.getElementsByTagName(&#39;head&#39;)[0].removeChild(obj);
    };

/* JS 替换非法字符主要用在密码验证上出现的特殊字符 */

function URLencode(sStr) {
    return escape(sStr).replace(/\+/g, &#39;%2B&#39;).replace(/\"/g, &#39;%22&#39;).replace(/\&#39;/g, &#39;%27&#39;).replace(/\//g, &#39;%2F&#39;);
};

/* 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();
    }
}

/* 获取当前时间 */

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 + &#39;-&#39; + month + &#39;-&#39; + days + &#39; &#39; + hours + &#39;:&#39; + minutes + &#39;:&#39; + seconds;
        return str;
    };
    function add_zero(temp) {
        if (temp < 10) return "0" + temp;
        else return temp;
    }

/* Js 去掉空格方法： */

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 引用 */

this.ClearHeadJs = function (src) {
    var js = document.getElementsByTagName(&#39;head&#39;)[0].children;
    var obj = null;
    for (var i = 0; i < js.length; i++) {
        if (js[i].tagName.toLowerCase() == "script" && js[i].attributes[&#39;src&#39;].value.indexOf(src) > 0) {
            obj = js[i];
        }
    }
    document.getElementsByTagName(&#39;head&#39;)[0].removeChild(obj);
};

/* 整个UL 点击事件加在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();
 };

以上就是本章的全部内容，更多相关教程请访问JavaScript视频教程！

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