<!DOCTYPE?html>
<html>
?<head>
??<title>?事件</title>??
??<script?type="text/javascript">
???function?count(){
????//獲取第一個輸入框的值
????????var?num1=parseInt(document.getElementById('txt1').value);
????????
????//獲取第二個輸入框的值
????????var?num1=parseInt(document.getElementById('txt2').value);
//獲取選擇框的值
????????var?select=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
????var?answer;
????switch(select){
????????case?'+':
????????????answer=num1+num2;
????????????break;
????????case?'-':
????????????answer=num1-num2;
????????????break;
????????case?'*':
????????????answer=num1*num2;
????????????break;
????????case?'/':
????????????answer=num1/num2;
????????????break;
????????default:
????????????answer=0;
????????????break;
????}
????//設(shè)置結(jié)果輸入框的值?
????document.getElementById('fruit').value=answer;
??
???}
??</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(diào)用創(chuàng)建的函數(shù)，得到結(jié)果-->?
???<input?type='text'?id='fruit'?/>???
?</body>
</html>
2015-04-20
你選自己的不就行了嘛。你都自問自答~~
2015-04-27
我喜歡你的選擇~~
2015-04-20
趕緊來人回答，我要結(jié)貼 啊哈哈哈
2015-04-20
沒有定義num2.。。。擦