Question

我通过点击nextDay和previousDay来增加和减少我的应用程序中的日期，日期正在递增但是一旦它达到月末31,30,29（feb），28（feb）那么它也应该改变月份也是日期。但它继续增加。直到现在我已尝试使用以下代码

   var today = new Date();
   var days = ["Sunday","Monday","Tuesday",
                 "Wednesday","Thursday","Friday","Saturday"];
   var months = ["January","February","March",
                 "April","May","June","July","August",
                 "September","October","November","December"];
   var nextDate = 0;

function set_todayDate（） {

document.getElementById("todaysDate").innerHTML = 
                        ""+days[today.getDay()]+",
                       "+months[today.getMonth()]+" 
                      "+today.getDate()+" 
                     "+today.getFullYear();

}

对于下一个日期和上一个日期，我正在增加和减少变量

      function nextDateMethod(){

        nextDate++;

    document.getElementById("todaysDate").innerHTML = ""+days[today.getDay()
      +dayIncrement]+ 
        ", "+months[today.getMonth()]+" 
      "+(today.getDate()+dayIncrement)+""+today.getFullYear();
    }



function prevDate(){
       nextDate--;

document.getElementById("todaysDate").
   innerHTML = months[today.getMonth()]+", 
     "+(today.getDate()+nextDate)+" "+today.getFullYear();
   }

请有人帮助我

Answer 1

试试这个：

＆＃13;

if (!Date.now) {
  Date.now = function() {
    return new Date().getTime();
  }
}
var theDate = Date.now();

document.getElementById('date').innerText = getTheDate(theDate)

document.getElementById('prev').addEventListener("click", function() {
  theDate -= 86400000;
  document.getElementById('date').innerText = getTheDate(theDate)
})
document.getElementById('next').addEventListener("click", function() {
  theDate += 86400000;
  document.getElementById('date').innerText = getTheDate(theDate)
})

function getTheDate(getDate) {
  var days = ["Sunday", "Monday", "Tuesday",
    "Wednesday", "Thursday", "Friday", "Saturday"
  ];
  var months = ["January", "February", "March",
    "April", "May", "June", "July", "August",
    "September", "October", "November", "December"
  ];
  var theCDate = new Date(getDate);
  return days[theCDate.getDay()] + ', ' + theCDate.getDate() + '-' + months[theCDate.getMonth()] + '-' + theCDate.getFullYear();
}

＆＃13;

<div id="date" style="height:100px; width:300px;">
</div>
<button id="prev">
  <</button>
    <button id="next">></button>

＆＃13;

Answer 2

我不明白为什么你的代码应该在日期达到30或31左右时自动更新月份。您正在使用getDate（）函数并返回一个数字。然后，您将它增加或减少1.它将简单地表现为var x=y+z。您将不得不操纵Date对象或必须手动配置月份和闰年等系统。我检查了http://www.w3schools.com/jsref/jsref_obj_date.asp处的日期参考对象，看起来你没有像C＃那样内置像addDays（）那样的功能。所以我想你必须手动实现日历规则。另外，请提及您声明并初始化nextDate

的位置

Answer 3

这是一个简单的函数，可以在给定日期添加任意天数，诀窍是使用日期对象的setDate方法

function addDays(date, days) {
    var result = new Date(date);
    result.setDate(result.getDate() + days);
    return result;
}

编辑：由于日期类是可变的，您还可以添加方法以方便将来使用

Date.prototype.addDays = function(days) {
    this.setDate(this.getDate() + parseInt(days));
    return this;
};

Answer 4

好吧，试试这个（下面是正在运行的样本）：

＆＃13;

var today = new Date();
 date = today.getDate();
 month= today.getMonth();
year= today.getFullYear();
month = month+1;

$("#Prev").click(function(){
   date = date -1;
  if(date<1){
  month = month -1;
    if(month == 0){
      year = year -1;
      date = 31;
      month = 12;
      } else{
      if(month == 2){
      date = 28
      } else if(month == 1 || month == 3 || month == 5 || month == 7 || month == 8 || month == 10 || month == 12){
       date = 31
      } else{
       date = 30
      }
      }
  }
  $("#displayDate")[0].innerHTML = date + "/" +  month + "/" + year;
});

$("#Next").click(function(){
   date = date + 1;
  if(date>28 && month == 2){
    date = 1;
    month = 3;
 } 
  if( date> 30 && (month == 4 || month == 6 || month == 9 || month == 11)){
  date = date +1;
    month = month +1;
  } else  if (date> 31){
  date =1; 
    month = month+1;
    if(month >12){
    year = year +1;
      month= 1; 
      date = 1;
    }
  }  
  
  $("#displayDate")[0].innerHTML = date + "/" +  month + "/" + year;
});

$("#displayDate")[0].innerHTML = date + "/" +  month + "/" + year;

＆＃13;

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div><button id="Prev">Prev</button><div id="displayDate"></div><button id="Next">Next</button></div>

＆＃13;

注意： Leap year的条件尚未添加但请告诉我是否是预期的答案我也会添加。

希望这会对你有所帮助:)。

Answer 5

有一个非常简洁的库，名为moment.js，它处理许多日期操作任务，并提供各种方便的方式来显示日期。网页和文档都做得很好，所以我认为值得看看他们的努力。

这就是增加日期日期所要求的工作如何查看.js：

var new_date_str = moment().add(1, 'days').format("dd, MMMM, D, YYYY");

请参阅此小提琴，了解完整的示例：https://jsfiddle.net/me6pdk8L/2/

通过点击Javascript

5 个答案: