求大神指导下哦点击“=”没有反应呢？

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<script type="text/javascript">
function count(){
    var num1=document.getElementById("num1").value ,
    symble=document.getElementById("symble"),    num2=document.getElementById("num2").value ,
    result;
        switch(symble){
            case"+":
            result=parseInt(num1)+parseInt(num2);
            break;
            case"-":
            result=parseInt(num1)-parseInt(num2);
            break;
            case"*":
            result=parseInt(num1)*parseInt(num2);
            break;
            case"/":
            result=parseInt(num1)/parseInt(num2);
            break;
            default:
            result=null;
            }
            document.getElementById("num3") = result;
        }

</script>>
<title>计算器简单功能实现</title>
</head>

<body>

<input type="text" name="num" id="num1">
<select id="symble">
<option>+</option>
<option>-</option>
<option selected="selected">*</option>
<option>/</option>
</select>
<input type="text" name="num" id="num2">
<input type="button" value="=" onclick = "count()">
<input type="text" name="num" id="num3">
</body>
</html>

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1回答

Caballarii

symble=document.getElementById("symble").value,document.getElementById("num3").value= result;两个地方

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求大神指导下哦 点击“=”没有反应呢？

1回答

求大神指导下哦点击“=”没有反应呢？