                        課程
                    
                        /前端開發
                        
                            /JavaScript
                        
                        /JavaScript進階篇

6-11 編程練習

<!DOCTYPE?html>
<html>
?<head>
??<title>?事件</title>??
??<script?type="text/javascript">
???function?count(){
?????var?txt1=document.getElementById("txt1").value;
?????var?txt2=document.getElementById("txt1").value;
?????var?sel=document.getElementById("select").value;
?????var?result="";
?????switch(sel){
?????????case?"+":
?????????result=parseInt(txt1)+parseInt(txt2);
?????????break;
?????????case?"-":
?????????result=parseInt(txt1)-parseInt(txt2);
?????????break;
?????????case?"*":
?????????result=parseInt(txt1)*parseInt(txt2);
?????????break;
?????????case?"/":
?????????result=parseInt(txt1)/parseInt(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>
		<option?value="/">/</option>
???</select>
???<input?type='text'?id='txt2'?/>?
???<input?type='button'?value='?=?'?onclick=count()?/>?<!--通過?=?按鈕來調用創建的函數，得到結果-->?
???<input?type='text'?id='fruit'?/>???
?</body>
</html>

哪里有問題？為什么我計算900/9就是1？