<!doctype html> <html> <head> <meta charset="utf-8"> <title>事件</title> <link href="css.css" rel="stylesheet" type="text/css"/> </head> <body> <div id="container"> <!DOCTYPE HTML> <html > <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>数组</title> <script type="text/javascript"> function count(){ //获取第一个输入框的值 var num1 = parseInt(document.getElementById("txt1").value); var num2 = parseInt(document.getElementById("txt2").value); var fu =document.getElementById("select").value; var jisuan; switch(fu) { case "+":jisuan= num1+num2;break; case "-":jisuan= num1-num2;break; case "*":jisuan= num1*num2;break; case "/":jisuan= num1/num2;break; default:break; } document.getElementById("fruit").value = jisuan; //获取第二个输入框的值 //获取选择框的值 //获取通过下拉框来选择的值来改变加减乘除的运算法则 //设置结果输入框的值 } </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()" /> <!--通过 = 按钮来调用创建的函数，得到结果--> <input type='text' id='fruit' /> </body> </html> </div> </body> </html>