明明就得不到正確結果課程頁地址：http://www.xianlaiwan.cn/code/1488<!DOCTYPE?html>
<html>
?<head>
??<title>?事件</title>??
??<script?type="text/javascript">
???function?count(){
??????var?first?=?document.getElementById("txt1").value;
??????var?sec?=?document.getElementById("txt2").value;
??????var?result?;
????//獲取第一個輸入框的值
????//獲取第二個輸入框的值
//獲取選擇框的值
??????var?selec?=?document.getElementById("select").value;
//獲取通過下拉框來選擇的值來改變加減乘除的運算法則
??????if?(select?===?"+"){
??????????result?=?first?+?sec;
??????}
??????else?if?(select?===?"-"?){
??????????result?=?first?-?sec;
??????}
??????else?if?(select?==="*"){
??????????result?=?first?*?sec;
??????}
??????else?if?(select?===?"/")
??????{
??????????result?=?first?/?sec;
??????}
????//設置結果輸入框的值?
??????var?theResult?=?document.getElementById("fruit");
??????theResult.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>..
為什么這樣的錯誤代碼也可以通過啊？
isu_騰飛
2014-12-02 20:16:17
