<!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>计算器</title> </head> <body> <input type="text" id="text1" /> <select id="xq"> <option value="+">+</option> <option value="-">-</option> <option value="*">*</option> <option value="/">/</option> </select> <input type="text" id="text2" /> <input type="button" value="=" onclick="count()" /> <input type="text" id="jg" /> </body> </html> <script type="text/javascript"> function count() { var a=document.getElementById("text1").value; var b=document.getElementById("text2").value; var c=document.getElementById("xq").value; var result=""; switch(c) { case"+":result=parseInt(a)+parseInt(b); break; case"-":result=parseInt(a)-parseInt(b); break; case"*":result=parseInt(a)*parseInt(b); break; default:result=parseInt(a)*parseInt(b); } document.getElementById("jg").value=result; } </script>