项目开发过程中，一些常用的方法

以下一些在开发过程中封装的常用方法，供参考由于一些方法是很久之前写下来的，语法上比较旧，再使用的时候再进行修改//获取当前时刻的时间

// type = 1年月日，type=2时分秒,fommatter="-"表示年月日用-隔开，否则用"/"隔开
export function curTimeFun(type,fommatter) {
  const myDate = new Date();
  const year = myDate.getFullYear()>9?myDate.getFullYear():‘0‘+myDate.getFullYear();
  const month = (myDate.getMonth() + 1)>9?myDate.getMonth() + 1:‘0‘+(myDate.getMonth() + 1);
  const date = myDate.getDate()>9?myDate.getDate():‘0‘+myDate.getDate();
  const h = myDate.getHours()>9?myDate.getHours():‘0‘+myDate.getHours();       //获取当前小时数(0-23)
  const m = myDate.getMinutes()>9?myDate.getMinutes():‘0‘+myDate.getMinutes();     //获取当前分钟数(0-59)
  const s = myDate.getSeconds()>9?myDate.getSeconds():‘0‘+myDate.getSeconds();
  let nowTime = "";
  if(type == ‘1‘){
    if(fommatter == ‘-‘) {
      nowTime = year + ‘-‘ + month + "-" + date;
    } else {
      nowTime = year + ‘/‘ + month + "/" + date;
    }
  } else if(type == ‘2‘){
    nowTime = h + ‘:‘ + m + ":" + s;
  } else {
    if(fommatter == ‘-‘) {
      nowTime = year + ‘-‘ + month + "-" + date + " " + h + ‘:‘ + m + ":" + s;
    } else {
      nowTime = year + ‘/‘ + month + "/" + date + " " + h + ‘:‘ + m + ":" + s;
    }
  }
  return nowTime;
}

// 获取今天星期几

export function getWeekFun() {
  const weekDay = [‘星期日‘,‘星期一‘,‘星期二‘,‘星期三‘,‘星期四‘,‘星期五‘,‘星期六‘]
  let week = new Date().getDay();
  return weekDay[week];
}

// 查询最近n年，n表示前多少年的意思// 例如查询近5年的时间，n=4，不包括今年的的前4年

export function getLastNYear(n) {
  const myDate = new Date;
  const curYear = myDate.getFullYear();
  if(n ==‘‘ || n==undefined || n == null){
    n =0;
  }
  let rstYear = curYear*1 - n*1;
  return rstYear;
}

// 查询最近n月，n表示前多少月的意思

export function getLastNMonth(n) {
  const myDate = new Date;
  const curYear = myDate.getFullYear();
  const curMonth = myDate.getMonth()+1; // 月份从0开始算起。需要加1
  if(n ==‘‘ || n==undefined || n == null){n =0;}
  let rstYear = ‘‘;
  let rstMonth = ‘‘;
  if(n>curMonth){ //表示去到去年的月份，年份需要去到上一年
    rstYear = curYear*1-1*1;
    rstMonth = 12-(n-curMonth)+1;
  } else {
    rstYear =curYear;
    rstMonth = curMonth -n;
  }
  rstMonth = (rstMonth)>9?rstMonth:‘0‘+(rstMonth);
  let rstYearMonth = rstYear + ‘-‘ + rstMonth;
  return rstYearMonth;
}

// 获取最近n天的时间，n表示前多少天的意思。
// 例如查询近7天的时间，n=6，不包括当天的的前6天

export function getLastNDate(n,fommatter = ‘-‘) {
  const d = new Date();
  var myDate=new Date(d.getTime()-86400000*n);  // 获取前n天的日期
  const year = myDate.getFullYear()>9?myDate.getFullYear():‘0‘+myDate.getFullYear();
  const month = (myDate.getMonth() + 1)>9?myDate.getMonth() + 1:‘0‘+(myDate.getMonth() + 1);
  const date = myDate.getDate()>9?myDate.getDate():‘0‘+myDate.getDate();

　let last7Date = year + fommatter + month + fommatter + date;　return last7Date;

return last7Date; }

// 获取最近的n个小时，n表示前多少小时的意思。

export function getLastNHour(n,fommatter = ‘-‘) {
  const d = new Date();
  var myDate=new Date(d.getTime()-86400000*n);  // 获取前n天的日期
  const year = myDate.getFullYear()>9?myDate.getFullYear():‘0‘+myDate.getFullYear();
  const month = (myDate.getMonth() + 1)>9?myDate.getMonth() + 1:‘0‘+(myDate.getMonth() + 1);
  const date = myDate.getDate()>9?myDate.getDate():‘0‘+myDate.getDate();
  const h = myDate.getHours()>9?myDate.getHours():‘0‘+myDate.getHours();       //获取当前小时数(0-23)
  const m = myDate.getMinutes()>9?myDate.getMinutes():‘0‘+myDate.getMinutes();     //获取当前分钟数(0-59)
  const s = myDate.getSeconds()>9?myDate.getSeconds():‘0‘+myDate.getSeconds();
　let  nowTime = year + fommatter + month + fommatter + date + " " + h + fommatter + m + fommatter + s;

return nowTime; }

/*菜单树下拉，禁止选择当前项及其子项，以防止死循环*/

export function diGuiTreeEdit(item,compID) {  // 编辑情况下，禁止选择当前节点及其子节点
  let data = item;
  let treeAry = [];
  for (let i in data) {
    let v = data[i];
    let node = {};
    if (v === null || v === undefined) {}
    else {
      if (v.children && v.children.length > 0) {
        if (v.id == compID) {
          node.isDisabled = true;
        } else {
          node.isDisabled = false;
        }
        node.id = v.id;
        node.label = v.label;
        node.name = v.name;
        node.children = diGuiTreeEdit(v.children, compID);
        treeAry.push(node);
      } else {
        if (v.id == compID) {
          node.isDisabled = true;
        } else {
          node.isDisabled = false;
        }
        node.id = v.id;
        node.label = v.label;
        node.name = v.name;
        treeAry.push(node);
      }
    }
  }
  return treeAry;
};

// 判断数据是否为空，为空的话返回指定的数值

export function isNullORFalse(checkVal,rstVal) {
  if(checkVal == ‘‘ || checkVal == null || checkVal == undefined || typeof(checkVal) == undefined){
    if(rstVal == null || rstVal == ‘‘){
      rstVal = "";
    }
    return rstVal;
  } else {
    return checkVal;
  }
}

// 全部替换

// str表示原字符串，s表示要被替换的内容,replaceStr用于替换的内容
export function repalceAll(str, s ,replaceStr = ‘‘) {
  var reg = new RegExp(s, "g")//g,表示全部替换
  return str.replace(reg,replaceStr)
}

//计算两个日期天数差的函数，通用,时间格式为yyyy-MM-dd格式

export function dateDiff(sDate1, sDate2) {  //sDate1和sDate2是yyyy-MM-dd格式
  let aDate, oDate1, oDate2, iDays
  aDate = sDate1.split("-")
  oDate1 = new Date(aDate[1] + ‘-‘ + aDate[2] + ‘-‘ + aDate[0])  //转换为yyyy-MM-dd格式
  aDate = sDate2.split("-")
  oDate2 = new Date(aDate[1] + ‘-‘ + aDate[2] + ‘-‘ + aDate[0])
  iDays = parseInt(Math.abs(oDate1 - oDate2) / 1000 / 60 / 60 / 24) //把相差的毫秒数转换为天数
  return iDays;  //返回相差天数
}

// 当数值过大是，超过9位数（亿）转为亿单位展示

export function rspHundredMill(val, unit = ‘HM‘) {
  if(unit == ‘HM‘) {
    if(val>100000000) { //大于1亿
      return (val/100000000).toFixed(3)+‘亿‘
    } else {
      return  val
    }
  }
}

// 根据id，以及id的值，遍历list对象，得出label

export function rstLabelFormID(list, id, label, idVal) {
  let rsp = ‘‘
  for (let i = 0; i < list.length; i++) {
    if (list[i][id] === idVal) {
      rsp = list[i][label]
      break
    }
  }
  return rsp
}

// 根据id，以及id的值，遍历list集合，得出对应的对象

export function rstListFormID(list, id, idVal) {
  let rsp = undefined
  for (let i = 0; i < list.length; i++) {
    if (list[i][id] === idVal) {
      rsp = list[i]
      break
    }
  }
  return rsp
}

// 对象深拷贝

export function deepCopy(obj) {
  var result = Array.isArray(obj) ? [] : {}
  for (var key in obj) {
    if (obj.hasOwnProperty(key)) {
      if (typeof obj[key] === ‘object‘ && obj[key] !== null) {
        result[key] = deepCopy(obj[key])
      } else {
        result[key] = obj[key]
      }
    }
  }
  return result
}

// 拖动调整左右两侧div的宽度

// resizeName表示拖到的工具条的className
// left表示左边的区域的className。leftWid表示左边的最小宽度
// midName表示右边区域的className。rightWid表示右边的最小宽度
// boxName表示父级元素的className
export function  dragControllerDiv(resizeName=‘resize‘, leftName = ‘left‘, midName = ‘mid‘, boxName = ‘box‘, leftWid = 250, rightWid = 800){
  var resize = document.getElementsByClassName(resizeName);
  var left = document.getElementsByClassName(leftName);
  var mid = document.getElementsByClassName(midName);
  var box = document.getElementsByClassName(boxName);
  for (let i = 0; i < resize.length; i++) {
    // 鼠标按下事件
    resize[i].onmousedown = function (e) {
      var startX = e.clientX;
      resize[i].left = resize[i].offsetLeft;
      // 鼠标拖动事件
      document.onmousemove = function (e) {
        var endX = e.clientX;
        var moveLen = resize[i].left + (endX - startX); // （endx-startx）=移动的距离。resize[i].left+移动的距离=左边区域最后的宽度
        var maxT = box[i].clientWidth - resize[i].offsetWidth;  // 容器宽度 - 左边区域的宽度 = 右边区域的宽度

        if (moveLen < leftWid) moveLen = leftWid; // 左边区域的最小宽度为150px
        if (moveLen > maxT - rightWid) moveLen = maxT  - rightWid;  //右边区域最小宽度为800px

        resize[i].style.left = moveLen; // 设置左侧区域的宽度

        for (let j = 0; j < left.length; j++) {
          left[j].style.width = moveLen + ‘px‘;
          mid[j].style.width = (box[i].clientWidth - moveLen - 10) + ‘px‘;
        }
      }
      // 鼠标松开事件
      document.onmouseup = function (evt) {
        document.onmousemove = null;
        document.onmouseup = null;
        resize[i].releaseCapture && resize[i].releaseCapture(); //当你不在需要继续获得鼠标消息就要应该调用ReleaseCapture()释放掉
      }
      resize[i].setCapture && resize[i].setCapture(); //该函数在属于当前线程的指定窗口里设置鼠标捕获
      return false;
    }
  }
}

原文地址：https://www.cnblogs.com/luoxuemei/p/11646108.html