javascript常用函数

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这里写自定义目录标题

实现字符串长度截

function cutstr(str, len) {
        var temp;
        var icount = 0;
        var patrn = /[^\\x00-\\xff]/;
        var 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 + "..."
    }

获取域名主机

function getHost(url) {
        var host = "null";
        if(typeof url == "undefined"|| null == url) {
            url = window.location.href;
        }
        var regex = /^\\w+\\:\\/\\/([^\\/]*).*/;
        var match = url.match(regex);
        if(typeof match != "undefined" && null != match) {
            host = match[1];
        }
        return host;
}

清除空格

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

替换全部

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

转义html标签

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

生javascript还原html标签

function HtmlDecode(text) {
   return text.replace(/&/g, '&').replace(/"/g, '\\"').replace(/, '<').replace(/>/g, '>')
}

时间日期格式转换

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
    }

判断是否为数字类型

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

设置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;"
    }

#获取cookie值

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

#加入收藏夹

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

#设为首页

function setHomepage() {
        if (document.all) {
            document.body.style.behavior = 'url(#default#homepage)';
            document.body.setHomePage('http://***')
        } else if (window.sidebar) {
            if (window.netscape) {
                try {
                    netscape.security.PrivilegeManager.enablePrivilege("UniversalXPConnect")
                } catch(e) {
                    alert("该操作被浏览器拒绝，如果想启用该功能，请在地址栏内输入 about:config,然后将项 signed.applets.codebase_principal_support 值该为true")
                }
            }
            var prefs = Components.classes['@mozilla.org/preferences-service;1'].getService(Components.interfaces.nsIPrefBranch);
            prefs.setCharPref('browser.startup.homepage', 'http://***')
        }
    }

判断IE6

var ua = navigator.userAgent.toLowerCase();
    var isIE6 = ua.indexOf("msie 6") > -1;
    if (isIE6) {
        try {
            document.execCommand("BackgroundImageCache", false, true)
        } catch(e) {}
    }

加载样式文件

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)
        }
    }

返回脚本内容

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

清除脚本内容

function stripscript(s) {
    return s.replace(/, '');
 }

动态加载脚本文件

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;
                };
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