Question

嗨，我想获得用户写的内容，将其乘以某个数字并在标题中显示结果。

    <!DOCTYPE html>
<html lang="en" dir="ltr">
  <head>
    <meta charset="utf-8">
    <title></title>
  </head>
  <body>
    <input type="text" id="number" name="num" value="">
    <div id = "output">
      <h2 id="OP"></h2>
    </div>
  </body>
</html>

var valResult = parseInt(document.getElementById("number").value);
var num = 5;
var results = valResult + num;
if (valResult == 10){
document.getElementById("OP").innerHTML = results;
}

Answer 1

您有一些不必要的代码。您真的需要：

if (valResult == 10){....

尝试以下操作：

function calculate(input){
  var valResult = parseInt(input.value);
  var num = 5;
  var results = valResult * num;
  document.getElementById("OP").innerHTML = results;  
}

<!DOCTYPE html>
<html lang="en" dir="ltr">
  <head>
    <meta charset="utf-8">
    <title></title>
  </head>
  <body>
    <input type="text" id="number" name="num" oninput="calculate(this)">
    <div id = "output">
      <h2 id="OP"></h2>
    </div>
  </body>
</html>

如何获得用户输入并输出值？

1 个答案: