哪里出错了？

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8" />
<script type="text/javascript">
function count(){

    var txt1 = parseInt(document.getElementById("txt1").value);

    var txt2 = parseInt(document.getElementById("txt2").value);

    var select1 = document.getElementById("select").value;

    var result="";
    switch(select1){
        case "+":
           result = txt1+txt2;
           break;
        case "-":
           result = txt1-txt2;
           break;
        case "*":
           result = txt1*txt2;
           break;
       default:
           result = txt1/txt2;
    }
  document.getElementById("fruit").value=result
   }
</script>
</head>
<body>
   <input type='text' id='txt1' />
   <select id='select'>
  <option value='+'>+</option>
  <option value="-">-</option>
  <option value="*">*</option>

慕粉3646148

浏览 1261回答 2

2回答

snowmanJS

Caballarii

<input type='button' value=' = ' onclick="count()"/>onclick要加引号

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