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                        /JavaScript進(jìn)階篇

救救孩子吧找不出問題就是輸不出結(jié)果

<!DOCTYPE?html>
<html>
?<head>?
??<title>?事件</title>????
??<script?type="text/javascript">??
???function?count(){??
?????var?one=document.getElementById("txt1").value;????
?????var?two=document.getElementById("txt2").value;	
?????var?a=doucument.getElementById("select").value;	
?????var?num;	
?????switch(a){	????
?????case?"+":	????????
?????????????num=parseInt(one)+parseInt(two);	??
?????????????break;	??
?????case?"-":
?????????????num=parseInt(one)-parseInt(two);	???
?????????????break;	???
?????case?"*":	?????
?????????????num=parseInt(one)*parseInt(two);	
?????????????break;	???
?????case?"/"?:	?????
?????????????num=parseInt(one)/parseInt(two);	??
?????????????break;	
????????????}	
???????document.getElementById("fruit").value=num;??
????}??</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>