告诉你正确答案,不过你那一分就不用给了<html>
<head>
<script language="javascript">
function operator(){
try{
var ix=-1,n=N("oper");for(i=0;i<4;i++){if(n[i].checked){ix=i;break;}}
I('result').value=eval("I('f').value*1"+n[ix].value+"I('s').value*1");
}catch(e){}
}
function I(i){return document.getElementById(i);}
function N(n){return document.getElementsByName(n);}
</script>
</head> <body>
<input type="text" id="f"><br>
<input type="text" id="s"><br>
<input type="radio" name="oper" value="+">相加<br>
<input type="radio" name="oper" value="-">想减<br>
<input type="radio" name="oper" value="*">相乘<br>
<input type="radio" name="oper" value="/">相除<br>
<input type="button" value="计算" onclick="operator()">
<input id="result">
</body>
</html>
<head>
<script language="javascript">
function operator(){
try{
var ix=-1,n=N("oper");for(i=0;i<4;i++){if(n[i].checked){ix=i;break;}}
I('result').value=eval("I('f').value*1"+n[ix].value+"I('s').value*1");
}catch(e){}
}
function I(i){return document.getElementById(i);}
function N(n){return document.getElementsByName(n);}
</script>
</head> <body>
<input type="text" id="f"><br>
<input type="text" id="s"><br>
<input type="radio" name="oper" value="+">相加<br>
<input type="radio" name="oper" value="-">想减<br>
<input type="radio" name="oper" value="*">相乘<br>
<input type="radio" name="oper" value="/">相除<br>
<input type="button" value="计算" onclick="operator()">
<input id="result">
</body>
</html>
今天第一天学习JavaScript,你这样写,虽然结果是出来了,但是我还是有点看不大明白,我那种方法能不能达到预期结果呢?出错在哪里呢?JavaScript脚步报未定义错