第十五节 JavaScript分之语句之加法运算

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <title>Document</title>
 6     <script type="text/javascript">
 7         window.onload = function(){
 8             var oInput01 = document.getElementById('input01');
 9             var oInput02 = document.getElementById('input02');
10             var oBtn = document.getElementById('btn');
11             oBtn.onclick = function(){
12                 var iVal01 = parseInt(oInput01.value);  // 将输入的字符串转换成int类型
13                 var iVal02 = parseInt(oInput02.value);
14                 alert(iVal01 + iVal02);
15             }
16         }
17     </script>
18 </head>
19 <body>
20     <input type="text" name="" id="input01">+
21     <input type="text" name="" id="input02">
22     <input type="button" name="" id="btn" value="相加">
23 </body>
24 </html>