為什么結(jié)果出不來
<!DOCTYPE html>
<html>
?<head>
? <title> 事件</title> ?
? <script type="text/javascript">
?? function count(){
??? var text1 = document.getElementById("txt1").value;
??? var text2 = document.getElementById("txt2").value;
??? var sel = document.getElementById("select").value;
??? // alert sel;
??? //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
?? ?//獲取通過下拉框來選擇的值來改變加減乘除的運(yùn)算法則
??? //設(shè)置結(jié)果輸入框的值
??? var d="";
??? switch(sel){
??????? case"+":
??????????? d=parseInt(text1)+parseInt(text2);
??????????? break;
??????? case"-":
??????????? d=parseInt(text1)-parseInt(text2);
??????????? break;
??????? case"*":
??????????? d=parseInt(text1)*parseInt(text2);
??????????? break;
??????? case"/":
??????????? d=parseInt(text1)/parseInt(text2);
??????????? break;
??????? default:
??????????? break;
??? }
???? document.getElementById("fruit").value = d;
?? }
? </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>
2016-04-14
<!DOCTYPE html>
<html>
?<head>
? <title> 事件</title> ?
? <script type="text/javascript">
?? function count(){
????? ?
??? //獲取第一個(gè)輸入框的值
??? var id1= parseInt(document.getElementById("txt1").value);
??? var id2= parseInt(document.getElementById("txt2").value);
?? ?//獲取第二個(gè)輸入框的值
?? ?//獲取選擇框的值
?? ?//獲取通過下拉框來選擇的值來改變加減乘除的運(yùn)算法則
??? //設(shè)置結(jié)果輸入框的值
??? // document.write(id1);
??? var sle=document.getElementById("select").value;
??? var counts=0;
??? switch(sle){
??????? case "+":
??????????? counts=id1+id2;
??????????? break;
??????? case "-":
??????????? counts=id1-id2;
??????????? break;
??????? case "*":
??????????? counts=id1*id2;
??????????? break;
??????? case "/":
??????????? counts=id1/id2;
??????????? break;
??? }
??? document.getElementById("fruit").value = counts;
?? }
? </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>
?? var text1 = document.getElementById("txt1").value;
??? var text2 = document.getElementById("txt2").value;
??? var sel = document.getElementById("select").value;
??? 你寫的反括號(hào)都是中文字符,改成英文字符就好了。