常用Javascript函数与原型功能收藏(必看篇)

// 重复字符串String.prototype.repeat = function(n) {  return new Array(n+1).join(this);} // 替换全部String.prototype.replaceAll = function(str1, str2) {  return this.replace(new RegExp(str1, "gm"), str2);} // 清除空格String.prototype.trim = function() {  return this.replace(/^/s*(.*?)/s+$/, "$1");} // 计算数组中的最大值Array.prototype.max = function() {  return Math.max.apply({}, this);} // 计算数组中的最小值Array.prototype.min = function() {  return Math.min.apply({}, this);} // 复制数组Array.prototype.copy = function() {  return [].concat(this);}; // 去除数组中指定元素，只能去除一个，如果想多个，之前先用unique处理Array.prototype.remove = function(value){  for (var i = 0, len = this.length; i < len; i++) {    if (this[i] == value) {      this.splice(i, 1);      break;    }  }  return this;} // 判断数组中是否存在指定元素，返回索引值Array.prototype.inArray = function(value) {  var index = -1, key;  for (key in this) {    if (this[key] == value) {      index = key;      break;    }  }  return index;} // 去除数组中的重复元素Array.prototype.unique = function() {  var key, ret = [];  for (key in this) {    if (ret.inArray(this[key]) < 0) {      ret.push(this[key]);    }  }  return ret;} // 检测是否已经安装flash，检测flash的版本var flashVersion = (function() {  var version;  try {    version = navigator.plugins['Shockwave Flash'];    version = version.description;  } catch (ex) {    try {      version = new ActiveXObject('ShockwaveFlash.ShockwaveFlash')        .GetVariable('$version');    } catch (ex2) {      version = '0.0';    }  }  version = version.match(//d+/g);  return parseFloat(version[0] + '.' + version[1], 10);})(); // 检测是否支持transitionvar supportTransition = (function() {  var s = document.createElement('p').style,    r = 'transition' in s ||    'WebkitTransition' in s ||    'MozTransition' in s ||    'msTransition' in s ||    'OTransition' in s;  s = null;  return r;})(); // 判断浏览器是否支持图片的base64var isSupportBase64 = (function() {  var data = new Image();  var support = true;  data.onload = data.onerror = function() {    if (this.width != 1 || this.height != 1) {      support = false;    }    return support;  };  data.src = "data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///ywAAAAAAQABAAACAUwAOw==";})(); // 首字母大写function ucfirst(str) {  return str.charAt(0).toUpperCase() + str.slice(1);} // 清除左空格function ltrim(str) {  return str.replace(/^(/s*|　*)/, "");} // 清除右空格function rtrim(str) {  return str.replace(/(/s*|　*)$/, "");} // 设置Cookie值function setCookie(name, value, hours, path, domain) {  var d = new Date();  var offset = 8;  var utc = d.getTime() + (d.getTimezoneOffset() * 60000);  var nd = utc + (3600000 * offset);  var expire = new Date(nd);  expire.setTime(expire.getTime() + hours * 60 * 60 * 1000);  var path = path || "";  var domain = domain || "";  document.cookie = name + "=" + escape(value) + ";path="+ path +";expires=" + expire.toGMTString() + ";domain="+ domain +";"} // 获取Cookie值function getCookie(name) {  var arr = document.cookie.match(new RegExp("(^| )" + name + "=([^;]*)(;|$)"));  if (arr != null) {    return unescape(arr[2]);  }  return null;} // 删除Cookie值function removeCookie(name) {  setCookie(name, "", -1);} // 生成范围随机数function rand(n, m) {  return Math.random() * (m - n) + n;} // 加入收藏夹function addFavorite(url, title) {  try {    window.external.addFavorite(url, title);  } catch(e) {    try {      window.sidebar.addPanel(title, url, "");    } catch(e) {      alert("加入收藏失败，请使用Ctrl+D进行添加");    }  }} // 设为首页function setHomepage(url) {  if (document.all) {    document.body.style.behavior = 'url(#default#homepage)';    document.body.setHomePage(url);  } 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', url);  }} // 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)  }} // 清除脚本内容function stripscript(str) {  return str.replace(/<script.*?>.*?<//script>/ig, '');} // 检验URL链接是否有效function getUrlState(url) {  var xmlhttp = new ActiveXObject("microsoft.xmlhttp");  xmlhttp.open("GET", url, false);  try {    xmlhttp.send();  } catch(e) {       } finally {    var result = xmlhttp.responseText;    if (result) {      if (xmlhttp.status == 200) {        return true;      } else {        return false;      }    } else {      return false;    }  }} // 格式化CSS代码function formatCss(str){  str = str.replace(//s*([/{/}/:/;/,])/s*/g, "$1");  str = str.replace(/;/s*;/g, ";"); //清除连续分号  str = str.replace(//,[/s/./#/d]*{/g, "{");  str = str.replace(/([^/s])/{([^/s])/g, "$1 {/n/t$2");  str = str.replace(/([^/s])/}([^/n]*)/g, "$1/n}/n$2");  str = str.replace(/([^/s]);([^/s/}])/g, "$1;/n/t$2");  return str;} // 压缩CSS代码function compressCss (str) {  str = str.replace(////*(.|/n)*?/*///g, "");    //删除注释  str = str.replace(//s*([/{/}/:/;/,])/s*/g, "$1");  str = str.replace(//,[/s/./#/d]*/{/g, "{");    //容错处理  str = str.replace(/;/s*;/g, ";");         //清除连续分号  str = str.match(/^/s*(/S+(/s+/S+)*)/s*$/);    //去掉首尾空白  return (str == null) ? "" : s[1];} // getElementsByClassNamefunction getElementsByClassName(name, context) {  var context = context || document;  if (context.getElementsByClassName) {    return context.getElementsByClassName(name);  }     var nodes = context.getElementsByTagName("*"), nodesLength = nodes.length, ret = [];  for (var i = 0; i < nodesLength; i++) {    var className = nodes[i].className;    if (nodes[i].nodeType == 1 && className) {      var classes = className.split(' ');      for (var j = 0; j < classes.length; j++) {        if (name == classes[j]) {          ret.push(nodes[i]);          break        }      }    }  }  return ret;} // 获取页面高度function getPageHeight() {  var doc = document;  var rot = doc.compatMode == "BackCompat" ? doc.body : doc.documentElement;  return Math.max(doc.documentElement.scrollHeight, doc.body.scrollHeight, rot.clientHeight);} // 获取页面scrollLeftfunction getPageScrollLeft() {  var doc = document;  return doc.documentElement.scrollLeft || doc.body.scrollLeft;} // 获取页面可视宽度function getPageViewWidth() {  var doc = document;  var rot = doc.compatMode == "BackCompat" ? doc.body : doc.documentElement;  return rot.clientWidth;} // 获取页面宽度function getPageWidth(){  var doc = document;  var rot = doc.compatMode == "BackCompat" ? doc.body : doc.documentElement;  return Math.max(doc.documentElement.scrollWidth, doc.body.scrollWidth, rot.clientWidth);} // 获取页面scrollTopfunction getPageScrollTop(){  var doc = document;  return doc.documentElement.scrollTop || doc.body.scrollTop;} // 获取页面可视高度function getPageViewHeight() {  var doc = document;  var rot = doc.compatMode == "BackCompat" ? doc.body : doc.documentElement;  return rot.clientHeight;} // 获取网页被卷去的位置function getScrollXY() {  return document.body.scrollTop ? {    x : document.body.scrollLeft,    y : document.body.scrollTop  } : {    x : document.documentElement.scrollLeft,    y : document.documentElement.scrollTop  }}// 获取元素的样式值function getStyle(elem, name) {  if (elem.style[name]) {    return elem.style[name];  } else if (elem.currentStyle) {    return elem.currentStyle[name];  } else if (document.defaultView && document.defaultView.getComputedStyle) {    var s = document.defaultView.getComputedStyle(elem, "");    return s && s.getPropertyValue(name);  } else {    return null;  }} // 获取元素相对于这个页面的X坐标function pageX(elem) {  return elem.offsetParent ? (elem.offsetLeft + pageX(elem.offsetParent)) : elem.offsetLeft;} // 获取元素相对于这个页面的Y坐标function pageY(elem) {  return elem.offsetParent ? (elem.offsetTop + pageY(elem.offsetParent)) : elem.offsetTop;} // 获取元素相对于父元素的X坐标function parentX(elem) {  return elem.parentNode == elem.offsetParent ? elem.offsetLeft : pageX(elem) - pageX(elem.parentNode);} // 获取元素相对于父元素的Y坐标function parentY(elem) {  return elem.parentNode == elem.offsetParent ? elem.offsetTop : pageY(elem)-pageY(elem.parentNode);} // 获取使用CSS定位的元素的X坐标function posX(elem) {  return parseInt(getStyle(elem, "left"));} // 获取使用CSS定位的元素的Y坐标function posY(elem) {  return parseInt(getStyle(elem, "top"));} // 设置元素X位置function setX(elem, pos) {  elem.style.left = pos + "px";} // 设置元素Y位置function setY(elem, pos) {  elem.style.top = pos + "px";} // 增加元素X坐标function addX(elem, pos) {  set(elem, (posX(elem) + pos));} // 增加元素Y坐标function addY(elem, pos) {  set(elem, (posY(elem) + pos));} // 获取元素使用CSS控制大小的高度function getHeight(elem) {  return parseInt(getStyle(elem, "height"));} // 获取元素使用CSS控制大小的宽度function getWidth(elem) {  return parseInt(getStyle(elem, "width"));} // 设置透明度function setOpacity(elem, num) {  if (elem.filters) {    elem.style.filter="alpha(opacity="+ num +")";  } else {    elem.style.opacity = num/100;  }} // 获取鼠标光标相对于整个页面的X位置function getX(e) {  e = e || window.event;  return e.pageX || e.clientX + document.body.scrollLeft;} // 获取鼠标光标相对于整个页面的Y位置function getY(e) {  e = e || window.event;  return e.pageY || e.clientY + document.body.scrollTop;} // 获取鼠标光标相对于当前元素的X位置function getElementX(e) {  return (e && e.layerX) || window.event.offsetX;} // 获取鼠标光标相对于当前元素的Y位置function getElementY(e) {  return (e && e.layerY) || window.event.offsetY;} // 获取滚动条的X位置function scrollX() {  var de = document.documentElement;  return self.pageXOffset || (de && de.scrollLeft) || document.body.scrollLeft;} // 获取滚动条的Y位置function scrollY() {  var de = document.documentElement;  return self.pageYOffset || (de && de.scrollTop) || document.body.scrollTop;} // 确认是否键盘有效输入值function checkKey(iKey) {  if (iKey == 32 || iKey == 229) {return true;} /*空格和异常*/  if (iKey>47 && iKey < 58)   {return true;} /*数字*/  if (iKey>64 && iKey < 91)   {return true;} /*字母*/  if (iKey>95 && iKey < 108)  {return true;} /*数字键盘1*/  if (iKey>108 && iKey < 112)  {return true;} /*数字键盘2*/  if (iKey>185 && iKey < 193)  {return true;} /*符号1*/  if (iKey>218 && iKey < 223)  {return true;} /*符号2*/  return false;} // 获得URL中GET参数值function getParams() {  var queryStr = window.location.href.split("?");  var params = [];  if (queryStr[1]) {    var gets = queryStr[1].split("&");    for (var i = 0; i < gets.length; i++) {      temp = gets.split("=");      params[temp[0]] = temp[1];    }  }  return params;} // 字符串反序function strReverse(text) {  return text.split('').reverse().join('');} // HTML实体function htmlEncode(str) {  var s = "";  if (str.length == 0) return "";  s = str.replace(//&/g, "&");  s = s.replace(/</g, "<");  s = s.replace(/>/g, ">");  s = s.replace(//'/g, "'");  s = s.replace(//"/g, "&qout;");  return s;} // HTML还原function htmlDecode(str) {  var s = "";  if (str.length == 0) return "";  s = str.replace(/&/g, "&");  s = s.replace(/</g, "<");  s = s.replace(/>/g, ">");  s = s.replace(/'/g, "/'");  s = s.replace(/&qout;/g, "/"");  return s;} // 克隆function clone(obj) {  var ret;  switch (typeof obj) {    case 'undefined':      break;    case 'string':      ret = obj + '';      break;    case 'number':      ret = obj - 0;      break;    case 'boolean':      ret = obj;      break;    case 'object':      if (obj === null) {        ret = null;      } else {        if (obj instanceof Array) {          ret = [];          for (var i = 0, len = obj.length; i < len; i++) {            ret.push(clone(obj[i]));          }        } else {          ret = {};          for (var k in obj) {            ret[k] = clone(obj[k]);          }        }      }      break;    default:      ret = obj;      break;  }  return ret;} // 检测变量是否为email格式function isEmail(mail) {  if (/^[/w-]+(/.[/w-]+)*@[/w-]+(/.[/w-]+)+$/.test(mail)) {    return true;  }  return false;} // 验证身份证号码function isIdenCode(code){  var city={11:"北京",12:"天津",13:"河北",14:"山西",15:"内蒙古",21:"辽宁",22:"吉林",23:"黑龙江 ",31:"上海",32:"江苏",33:"浙江",34:"安徽",35:"福建",36:"江西",37:"山东",41:"河南",42:"湖北 ",43:"湖南",44:"广东",45:"广西",46:"海南",50:"重庆",51:"四川",52:"贵州",53:"云南",54:"西藏 ",61:"陕西",62:"甘肃",63:"青海",64:"宁夏",65:"新疆",71:"台湾",81:"香港",82:"澳门",91:"国外"};  var tip = "";  var pass = true;  if (!code || !/^/d{6}(18|19|20)?/d{2}(0[1-9]|1[012])(0[1-9]|[12]/d|3[01])/d{3}(/d|X)$/i.test(code)) {    tip = "身份证号格式错误";    pass = false;  } else if (!city[code.substr(0,2)]) {    tip = "地址编码错误";    pass = false;  } else {    //18位身份证需要验证最后一位校验位    if(code.length == 18){      code = code.split('');      //∑(ai×Wi)(mod 11)      //加权因子      var factor = [ 7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2 ];      //校验位      var parity = [ 1, 0, 'X', 9, 8, 7, 6, 5, 4, 3, 2 ];      var sum = 0;      var ai = 0;      var wi = 0;      for (var i = 0; i < 17; i++) {        ai = code[i];        wi = factor[i];        sum += ai * wi;      }             var last = parity[sum % 11];      if (parity[sum % 11] != code[17]) {        tip = "校验位错误";        pass = false;      }    }  }  return pass;} // 检测变量是否为小数function isDecimal(dec){  if (dec.match(/^-?/d+(/./d+)?$/g) == null) {    return false;  }  return true;} // 检测变量是否为整型function isInteger(num){  if (num.match(/^[-+]?/d*$/) == null) {    return false;  }  return true;} // 检测变量是否为时间格式function checkTime(str) {  var time = str.match(/^(/d{1,2})(:)?(/d{1,2})/2(/d{1,2})$/);  if (time == null) {    return false;  }     if (time[1] > 24 || time[3] > 60 || time[4] > 60) {    return false  }  return true;} // 检测变量类型是否为日期格式function checkDate(str) {  var date = str.match(/^(/d{1,4})(-|//)(/d{1,2})/2(/d{1,2})$/);  if (date == null) {    return false;  }     var d = new Date(r[1], r[3]-1, r[4]);  return (d.getFullYear() == r[1] && (d.getMonth()+1) == r[3] && d.getDate() == r[4]);} // 检测变量是否为长日期格式function checkDateTime(str) {  var reg = /^(/d{1,4})(-|//)(/d{1,2})/2(/d{1,2}) (/d{1,2}):(/d{1,2}):(/d{1,2})$/;  var dt = str.match(reg);  if (dt == null) {    return false;  }     var d = new Date(dt[1], dt[3]-1, dt[4], dt[5], dt[6], dt[7]);  return (d.getFullYear() == dt[1] && (d.getMonth()+1) == dt[3] && d.getDate() == dt[4] && d.getHours() == dt[5] && d.getMinutes() == dt[6] && d.getSeconds() == dt[7]);} // 检测变量是否为未定义function isUndefined(val) {  return typeof val === 'undefined';} // 检测变量是否为定义function isDefined(val) {  return typeof val !== 'undefined';} // 检测变量类型是否为对象function isObject(val) { return val !== null && typeof val === 'object';} // 检测变量类型是否为空对象function isBlankObject(val) { return val !== null && typeof val === 'object' && !Object.getPrototypeOf(val);} // 检测变量类型是否为字符串function isString(val) {  return typeof val === 'string';} // 检测变量类型是否为数字function isNumber(val) {  return typeof val === 'number';} // 检测变量类型是否为日期function isDate(val) {  return toString.call(val) === '[object Date]';} // 检测变量类型是否为函数function isFunction(val) {  return typeof val === 'function';} // 检测变量类型是否为正则表达式function isRegExp(val) {  return toString.call(val) === '[object RegExp]';} // 检测变量是否window窗体对象function isWindow(obj) {  return obj && obj.window === obj;} // 检测变量类型是否为布尔function isBoolean(val) {  return typeof val === 'boolean';} // 检测变量类型是否为文件对象function isFile(obj) {  return toString.call(obj) === '[object File]';} // 检测变量类型是否为表单对象function isFormData(obj) {  return toString.call(obj) === '[object FormData]';} // 检测变量类型是否为二进制对象function isBlob(obj) {  return toString.call(obj) === '[object Blob]';} // 转全角字符function toDBC(str) {  var result = "";  var len = str.length;  for (var i = 0; i < len; i++) {    var code = str.charCodeAt(i);    //全角与半角相差（除空格外）：65248(十进制)    code = (code >= 0x0021 && code <= 0x007E) ? (code + 65248) : code;    //处理空格    code = (code == 0x0020) ? 0x03000 : code;    result += String.fromCharCode(code);  }  return result;} // 转半角字符function toSBC(str) {  var result = "";  var len = str.length;  for (var i = 0; i < len; i++) {    var code = str.charCodeAt(i);    //全角与半角相差（除空格外）：65248（十进制）    code = (code >= 0xFF01 && code <= 0xFF5E) ? (code - 65248) : code;    //处理空格    code = (code == 0x03000) ? 0x0020 : code;    result += String.fromCharCode(code);  }  return result;} // 全角半角转换// angle: 0全到半，1半到全，其他不转化function chgAngle(str, angle) {  if (typeof str != "string" || str.length <= 0 || !(angle === 0 || angle == 1)) {    return str;  }     var i, len, ret = [], code;  if (angle) {    /*半->全*/    for (i = 0, len = str.length; i < len; i++) {      code = str.charCodeAt(i);      if (code == 32) {        code = 12288;      } else if (code < 127) {        code += 65248;      }      ret.push(String.fromCharCode(code));    }  } else {    /*全->半*/    for (i = 0, len = str.length; i < len; i++) {      code = str.charCodeAt(i);      if (code == 12288) {        code = 32;      } else if (code > 65280 && code < 65375) {        code -= 65248;      }      ret.push(String.fromCharCode(code));    }  }  return ret.join("");} // 数据的本地化存储function makeWebStorage() {  //IE用userdata实现，w3c浏览器本身支持  if (("localStorage" in window)) {    var store = {      set  : function(key, value) {localStorage.setItem(key, value)},      get  : function(key)    {return localStorage.getItem(key)},      remove : function(key)    {return localStorage.removeItem(key)}    }  } else {    var store = {      userData : null,      name   : location.hostname,      init   : function () {        if (!store.userData) {          try {            store.userData = document.createElement('INPUT');            store.userData.type = "hidden";            store.userData.style.display = "none";            store.userData.addBehavior("#default#userData");            document.body.appendChild(store.userData);            var expires = new Date();            expires.setDate(expires.getDate() + 365);            store.userData.expires = expires.toUTCString();          } catch (e) {            return false;          }        }        return true;      },      setItem : function(key, value) {        if (store.init()) {          store.userData.load(store.name);          store.userData.setAttribute(key, value);          store.userData.save(store.name);        }      },      getItem : function(key) {        if (store.init()) {          store.userData.load(store.name);          return store.userData.getAttribute(key);        }      },      remove : function(key) {        if (store.init()) {          store.userData.load(store.name);          store.userData.removeAttribute(key);          store.userData.save(store.name);        }      }    };  }  window.webStorage = store;} function makeSessionStorage() {  if (("sessionStorage" in window)) {    var store = {      set  : function(key, value) {window.sessionStorage.setItem(key, value)},      get  : function(key)    {return window.sessionStorage.getItem(key)},      remove : function(key)    {return window.sessionStorage.removeItem(key)}    }  } else {    var store = {      set  : function(key, value) {},      get  : function(key)    {},      remove : function(key)    {}    }  }  window.sessStorage = store;}