<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>简易计算器</title> <script language="javascript"> function add(){ var num1=parseInt(document.getElementById("num1").value); var num2=parseInt(document.getElementById("num2").value); var result=document.getElementById("result"); result.value=num1+num2; } function sub(){ var num1=parseInt(document.getElementById("num1").value); var num2=parseInt(document.getElementById("num2").value); var result=document.getElementById("result"); result.value=num1-num2; } function mul(){ var num1=parseInt(document.getElementById("num1").value); var num2=parseInt(document.getElementById("num2").value); var result=document.getElementById("result"); result.value=num1*num2; } function div(){ var num1=parseInt(document.getElementById("num1").value); var num2=parseInt(document.getElementById("num2").value); var result=document.getElementById("result"); result.value=num1/num2; } </script> <style type="text/css"> body { height: 350px; width: 300px; margin-top: 50px; margin-left: 50px; line-height: 45px; } </style> </head> <body> num1:<input name="num1" type="text" id="num1" /><br /> num2:<input name="num2" type="text" id="num2" /><br /> <input name="add" type="button" value="+" onclick="add()"/> <input name="sub" type="button" value="-" onclick="sub()"/> <input name="mul" type="button" value="*" onclick="mul()"/> <input name="div" type="button" value="/" onclick="div()"/><br /> result:<input name="result" type="text" id="result" /><br /> </body> </html>
原文：http://www.cnblogs.com/caidupingblogs/p/4926387.html