常用函数封装整理-摩杜云开发者社区

阻止对象默认行为

//preDef(Event对象)

function preDef(ev){
    var ev = ev || window.event;
    if(ev.preventDefault){
        ev.preventDefault();
    }else {
        ev.returnValue = false;
    }
}

获取触发事件目标

//getTarget(Event对象)

function getTarget(ev){
    var ev = ev || window.event;
    if(ev.target){
        return ev.target;
    }else if(window.event.srcElement){
        return window.event.srcElement;
    }
}

获取滚动条位置

//获取滚动条的位置，即滚动距离，返回的结果是一个对象

function getSP(){
    return {
        top : document.documentElement.scrollTop || document.body.scrollTop,
        left : document.documentElement.scrollLeft || document.body.scrollLeft
    }
}

获取可视化窗口大小

function getWindow() {
  if(window.innerWidth !== void 0) {
    return {
      width: window.innerWidth,
      height: window.innerHeight
    }
  } else {
    return {
      width: document.documentElement.clientWidth,
      height: document.documentElement.clientHeight
    }
  }
}

获取屏幕坐标

//获取鼠标的位置信息,该位置为鼠标在整个页面的位置，而不是可视化窗口的位置

function getMouse(ev) {
  if(ev.pageX !== void 0) {
    return {
      x: ev.pageX,
      y: ev.pageY
    };
  }
  return {
    x: ev.clientX + document.body.scrollLeft - document.body.clientLeft,
    y: ev.clientY + document.body.scrollTop - document.body.clientTop
  }
}

js拖拽效果(目标相对定位)

//实现JS的拖拽效果,利用相对定位实现  onDrop(dom节点)

function onDrop(ele) {
  if(ele.nodeType === 1) {
    ele.style.position = "relative";
    ele.onmousedown = function(ev) {
      var ev = ev || window.event;
      var diffX = ev.clientX - parseInt(ele.style.left + "0"),
        diffY = ev.clientY - parseInt(ele.style.top + "0");
      document.onmousemove = function(e) {
        var e = e || window.event;
        ele.style.left = e.clientX - diffX + "px";
        ele.style.top = e.clientY - diffY + "px";
      };
      document.onmouseup = function(e) {
        var e = e || window.event;
        this.onmousemove = null;
        this.onmouseup = null;
      };
    }
  }
}

判断类型

//判断数据类型，返回首字母大写的字符串

function getType(ob){
    return ({}).toString.call(ob).match(/(\w+)]$/)[1];
}

数组去重

//返回没有重复值的新数组(多个NaN也视为重复)
//ES6最简 [...new Set([1,2,3,1,2,1,4])]
//ES5最简 [1,2,3,1,4,1,2,1].filter(function(e,i,arr){return i===arr.indexOf(e)})

function unique(arr) {
  var a = [],
    hasNaN = false;
  for(var i = 0; i < arr.length; i++) {
    if(a.indexOf(arr[i]) == -1) {
      if(arr[i] !== arr[i]) {
        if(hasNaN) {
          continue;
        }
        hasNaN = true;
      }
      a.push(arr[i]);
    }
  }
  return a;
}

深度克隆

//实现深度克隆对象

function clone(ob) {
  if(typeof ob === "object") {
    var newOb = ({}).toString.call(ob) === "[object Array]" ? [] : {};
    for(var name in ob) {
      newOb[name] = typeof ob[name] === "object" ? clone(ob[name]) : ob[name];
    }
    return newOb;
  } else {
    return ob;
  }
}

获取时间

//返回格式化后的时间,str为格式化样式,默认为(yyyy-MM-dd HH:mm:ss),date为时间对象，默认为当前时间

function getTime(str,date){
  var str = str || "yyyy-MM-dd HH:mm:ss";
  var date = date || new Date();
  var obj = {
    yyyy:date.getFullYear(),
    yy:(""+ date.getFullYear()).slice(-2),
    M:date.getMonth()+1,
    MM:("0"+ (date.getMonth()+1)).slice(-2),
    d:date.getDate(),
    dd:("0" + date.getDate()).slice(-2),
    H:date.getHours(),
    HH:("0" + date.getHours()).slice(-2),
    h:date.getHours() % 12,
    hh:("0"+date.getHours() % 12).slice(-2),
    m:date.getMinutes(),
    mm:("0" + date.getMinutes()).slice(-2),
    s:date.getSeconds(),
    ss:("0" + date.getSeconds()).slice(-2),
    w:"星期"+['日', '一', '二', '三', '四', '五', '六'][date.getDay()]  };
  return str.replace(/([a-z]+)/ig,function($1){return obj[$1]});
}

随机产生颜色

//产生16进制的颜色值

function getColor(){
    return "#"+Math.random().toString(16).substr(2,6);
}

天数跟秒转换

//天数跟秒之间的转换,适用于倒计时,秒杀..
//例如"1天12小时12分32秒"<==>130352之间相互转换

function changeTime(t) {
  if(typeof t === "string") {
    var num = 0;
    t.replace(/(\d+)(天|小时|分|秒)/g, function(a, b, c) {
      switch(c) {
        case "天":
          num += (+b) * 86400;
          break;
        case "小时":
          num += (+b) * 3600;
          break;
        case "分":
          num += (+b) * 60;
          break;
        case "秒":
          num += (+b);
          break;
      }
    });
    return num;
  } else if(typeof t === "number") {
    var time = "",
      ob = {
        "天": 86400,
        "小时": 3600,
        "分": 60,
        "秒": 1
      };
    if(t < 0) return "0秒";
    for(var name in ob) {
      var num = ob[name];
      if(t >= num) {
        time += (t / num | 0) + name;
        t %= num;
      }
    }
    return time;
  }
}

JS千分隔位

//每3位数加个逗号，保留两位小数
//123456.454==>123,456.45

function separator(str){
    if(!isNaN(+str)){
        str = (+str).toFixed(2);
        return str.replace(/\B(?=(?:\d{3})+\.)/g,",");
    }
}

获取计算后样式

//获取某个节点计算后样式,参数为dom节点,属性名称

function getCpStyle(ele,attribute){
    if(typeof getComputedStyle === "function"){
        return getComputedStyle(ele)[attribute];
    }else if(ele.currentStyle){
        return ele.currentStyle[attribute];
    }
}

获取XMLHTTPRequest对象

//返回一个XMLHTTPRequest对象

function getXHR() {
  var xhr;
  if(window.XMLHttpRequest) {
    xhr = new XMLHttpRequest();
  } else if(window.ActiveXObject) {
    xhr = new ActiveXObject("Microsoft.XMLHttp");
  }
  return xhr;
}

类名操作

//类似jq的toggleClass,没有就添加,有就删除

function setClass(ele, className) {
  if(ele.className !== void 0) {
    var str = ele.className,
      reg = new RegExp("\\b" + className + "\\s");
    if(reg.test(str)) {
      str = str.replace(reg, "");
    } else {
      str += " " + className + " ";
    }
    ele.className = str.replace(/\s+/, " ");
  }
}

cookie操作

var docCookies = {
  getItem: function(sKey) {
    return decodeURIComponent(document.cookie.replace(new RegExp("(?:(?:^|.*;)\\s*" + encodeURIComponent(sKey).replace(/[\-\.\+\*]/g, "\\$&") + "\\s*\\=\\s*([^;]*).*$)|^.*$"), "$1")) || null;
  },
  setItem: function(sKey, sValue, vEnd, sPath, sDomain, bSecure) {
    if(!sKey || /^(?:expires|max-age|path|domain|secure)$/i.test(sKey)) {
      return false;
    }
    var sExpires = "";
    if(vEnd) {
      switch(vEnd.constructor) {
        case Number:
          sExpires = vEnd === Infinity ? "; expires=Fri, 31 Dec 9999 23:59:59 GMT" : "; max-age=" + vEnd;
          break;
        case String:
          sExpires = "; expires=" + vEnd;
          break;
        case Date:
          sExpires = "; expires=" + vEnd.toUTCString();
          break;
      }
    }
    document.cookie = encodeURIComponent(sKey) + "=" + encodeURIComponent(sValue) + sExpires + (sDomain ? "; domain=" + sDomain : "") + (sPath ? "; path=" + sPath : "") + (bSecure ? "; secure" : "");
    return true;
  },
  removeItem: function(sKey, sPath, sDomain) {
    if(!sKey || !this.hasItem(sKey)) {
      return false;
    }
    document.cookie = encodeURIComponent(sKey) + "=; expires=Thu, 01 Jan 1970 00:00:00 GMT" + (sDomain ? "; domain=" + sDomain : "") + (sPath ? "; path=" + sPath : "");
    return true;
  },
  hasItem: function(sKey) {
    return(new RegExp("(?:^|;\\s*)" + encodeURIComponent(sKey).replace(/[\-\.\+\*]/g, "\\$&") + "\\s*\\=")).test(document.cookie);
  }
};

Ajax对象封装

var Ajax = {
  get: function(url, fn) {
    var obj = new XMLHttpRequest();
    obj.open('GET', url, true);
    obj.onreadystatechange = function() {
      if(obj.readyState == 4 && obj.status == 200 || obj.status == 304) {
        fn.call(this, obj.responseText);
      }
    };
    obj.send();
  },
  post: function(url, data, fn) {
    var obj = new XMLHttpRequest();
    obj.open("POST", url, true);
    obj.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    obj.onreadystatechange = function() {
      if(obj.readyState == 4 && (obj.status == 200 || obj.status == 304)) {
        fn.call(this, obj.responseText);
      }
    };
    obj.send(data);
  }
}