js获取当前周、上一周、下一周日期-蒲公英云

js获取当前周、上一周、下一周日期

秒速五厘米 2021-09-16 07:16 1358阅读 0赞

最近在做一个课表的功能，需实现选择了第几周之后，该周相关的日期会自动更改过来，于是就在网上找了资料，经过一下午的折腾，终于把它实现了。

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虽然是用在小程序中，但js代码都是大同小异的，只需做一些小小的修改。如果你是用在web网页中，那么就不需要怎么修改了，下面我们来看代码。

1、获取当前周、上一周、下一周日期

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html >
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
  <title>日历操作</title>
  <script>
    window.onload = function(){     
      var cells = document.getElementById('monitor').getElementsByTagName('td');
      var clen = cells.length;
      var currentFirstDate;
      var formatDate = function(date){       
        var year = date.getFullYear()+'年';
        var month = (date.getMonth()+1)+'月';
        var day = date.getDate()+'日';
        var week = '('+['星期天','星期一','星期二','星期三','星期四','星期五','星期六'][date.getDay()]+')'; 
        return year+month+day+'  '+week;
      };
      var addDate= function(date,n){    
        date.setDate(date.getDate()+n);    
        return date;
      };
      var setDate = function(date){       
        var week = date.getDay()-1;
        date = addDate(date,week*-1);
        currentFirstDate = new Date(date);
        for(var i = 0;i<clen;i++){         
          // cells[i].innerHTML = formatDate(i==0 ? date : addDate(date,1));    星期一开始
          cells[i].innerHTML = formatDate(i==0 ? addDate(date,-1) : addDate(date,1));//星期日开始
        }        
      };
      document.getElementById('last-week').onclick = function(){
        setDate(addDate(currentFirstDate,-7));     
      };       
      document.getElementById('next-week').onclick = function(){         
        setDate(addDate(currentFirstDate,7));
      };   
      setDate(new Date());
    }
  </script>
</head>
<body>
  <button id="last-week">上一周</button><button id="next-week">下一周</button>
  <table id="monitor">
    <tr>
      <td></td>
      <td></td>
      <td></td>
      <td></td>
      <td></td>
      <td></td>
      <td></td>
    </tr>
  </table>
</body>
</html>

2、改造后（点击周数，显示对应周数的日期）

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html >
<head>
  <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
  <title>js通过给出第几周，获得该周日历（课表日历）</title>
  <script type="text/javascript" src="js/jquery-1.7.1.min.js"></script>
  <script>
    window.onload = function(){     
      var cells = document.getElementById('monitor').getElementsByTagName('td');
      var clen = cells.length;
      var currentFirstDate;
      var formatDate = function(date){       
        var year = date.getFullYear()+'年';
        var month = (date.getMonth()+1)+'月';
        var day = date.getDate()+'日';
        var week = '('+['星期天','星期一','星期二','星期三','星期四','星期五','星期六'][date.getDay()]+')'; 
        return year+month+day+'  '+week;
      };
      var addDate= function(date,n){    
        date.setDate(date.getDate()+n);    
        return date;
      };
      var setDate = function(date){       
        var week = date.getDay()-1;
        date = addDate(date,week*-1);
        currentFirstDate = new Date(date);
        for(var i = 0;i<clen;i++){         
           cells[i].innerHTML = formatDate(i==0 ? date : addDate(date,1));   //星期一开始
          //cells[i].innerHTML = formatDate(i==0 ? addDate(date,-1) : addDate(date,1));   //星期天开始
        }        
      };
          var chushi=1;//初始周 第1周
          //使用each()方法进行循环
        $("button").each(function(index,element){
            //这里的index就是当前对象下标，element就是当前对象（dom对象）
            $(element).click(function(){
                console.log($(this).text());
                var value=$(this).text();
                //这里的周跟当前周(上一次点击的或初始的)进行比较
                console.log(value-chushi);
                var result=value-chushi;
                if(result>0){
                    setDate(addDate(currentFirstDate,7*result));     
                }
                else if(result<0){
                    result= Math.abs(result);  
                    setDate(addDate(currentFirstDate,-(7*result)));
                }
                else if(result==0){
                    setDate(addDate(currentFirstDate,0));
                }
                chushi=$(this).text();
            })
        })
      setDate(new Date());
    }
  </script>
</head>
<body>
  <button class="zhou">1</button>
  <button class="zhou">2</button>
  <button class="zhou">3</button>
  <button class="zhou">4</button>
  <button class="zhou">5</button>
  <button class="zhou">6</button>
  <button class="zhou">7</button>
  <button class="zhou">8</button>
  <button class="zhou">9</button>
  <button class="zhou">10</button>
  <table id="monitor">
    <tr>
      <td></td>
      <td></td>
      <td></td>
      <td></td>
      <td></td>
      <td></td>
      <td></td>
    </tr>
  </table>
</body>
</html>