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<!DOCTYPE?html>
<html>
?<head>
??<title>?事件</title>??
??<script?type="text/javascript">
???function?count(){
?????//??var?x,y,z,count1;
??????var?x=document.getElementById("txt1").value;
??????var?y=document.getElementById("txt2").value;
??????var?z=document.getElementById("select").value;
??????var?count1="";
???????switch(z)
???????case?"+":count1=parseInt(x)+parseInt(y);break;
???????case?"-":count1=parseInt(x)-parseInt(y);break;
???????case?"*":count1=parseInt(x)*parseInt(y);break;
???????default:count1=parseInt(x)/parseInt(y);
???????document.getElementById("fruit").value=count1;
????//獲取第一個(gè)輸入框的值
//獲取第二個(gè)輸入框的值
//獲取選擇框的值
//獲取通過(guò)下拉框來(lái)選擇的值來(lái)改變加減乘除的運(yùn)算法則
????//設(shè)置結(jié)果輸入框的值?
???}
??</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(guò)?=?按鈕來(lái)調(diào)用創(chuàng)建的函數(shù)，得到結(jié)果-->?
???<input?type='text'?id='fruit'?onClick="count()"?/>???
?</body>
</html>