Question

document.getElementById获取元素（即p标签）但是尽快获得它写入内容消失。控制台上没有错误，但只要在p标签上写入任何内容，p标签中写入的内容就会消失。

我找不到任何理由它也不工作我也不允许使用php接受表单输入。

 
 

var d=new Date();
 var cday=d.getDay();
 var cmonth=d.getMonth();
 var cyear=d.getFullYear();
 var day,month,year,dage,mage,yage;
 function getDOB() {
  var DOB = new Date(document.getElementById("DOB").value);
  year = DOB.getFullYear();
  month = DOB.getMonth();
  day = DOB.getDay();
}

document.getElementById("inp").onclick = function execute() {
  getDOB();
  yage = cyear - year;

  if (cmonth >= month) {
    mage = cmonth - month;
  } else {
    mage = 12 - (month - cmonth);
    yage = yage - 1;
  }

  if (cday >= day) {
    dage = cday - day;
  } else {
    mage = mage - 1
    dage = 30 - (day - cday);
  }

  document.getElementById("output").innerHTML = "your age is " + dage + " days " + mage + " months " + yage + " years";
}

<html>

<head>
</head>

<body>
  <p id="month">
  </p>
  <form id="form">
    <!input type="text" id="day" placeholder="dd">
    <! input type="text" id="day" placeholder="mm">
    <!input type="text" id="day" placeholder="yyyy">
    <input type="date" id="DOB">
    <button id="inp">submit</button>
    <br>
  </form>
  <p id="output"></p>
  <script src="age.js"></script>
</body>

</html>

Answer 1

您的代码包含早期错误，但尚未达到innerHTML。

以下是错误：

未捕获的ReferenceError：未定义cyear

您还必须在函数末尾添加return false;以阻止表单提交，如@thewatcheruatu所述。

Answer 2

date=new Date();           // Get current date
cyear=date.getFullYear();  // current year
cmonth=date.getMonth()+1;  // current month
cday=date.getDate();       // current day

function getDOB()
    {
        var DOB=new Date(document.getElementById("DOB").value);
        year=DOB.getFullYear();
        month=DOB.getMonth();
        day=DOB.getDate();     // getDate() function returns the current date      
    }

function execute()
    {
        getDOB();
        yage=cyear-year;
        if( cmonth>=month)
        {
            mage=cmonth-month;
        }
        else
        {
                mage=12-(month-cmonth);
                yage=yage-1;
        }
        if ( cday>=day )
        {
            dage=cday-day;
        }
        else
        {
            mage=mage-1
            dage=30-(day-cday);
        }
        document.getElementById("output").innerHTML="your age is "+dage+" days "+mage+" months "+yage+ " years";
    }

<html>
<head>
</head>
<body>
    <p id="month">
    </p>
    <form id="form">
        <!input type="text" id="day" placeholder="dd">
        <! input type="text" id="day" placeholder="mm">
        <!input type="text" id="day" placeholder="yyyy">
        <input type="date" id="DOB">
        <button type="button" id="inp" onclick="execute()">submit</button><br>
    </form>
    <p id="output"></p>
<script src="age.js"></script>
</body>
</html>

document.getElementById.innerHTML不起作用

2 个答案: