<!DOCTYPE html> <html> <head> <title>实现计算功能</title> </head> <body> <script type="text/javascript"> function count() {var a=document.getElementById("t1").value; var b=document.getElementById("t2").value; var c=""; var s=document.getElementById("select").value; switch(s) {case "+": c=parseInt(a)+parseInt(b); break; case "-": c=parseInt(a)-parseInt(b); break; case "*": c=parseInt(a)*parseInt(b); break; default: c=parseInt(a)/parseInt(b); } document.getElementById("t3").value=c; } </script> <form> <input id="t1" type="text" /> <select id="select"> <option value="+">+</option> <option value="-">-</option> <option value="*">*</option> <option value="/">/</option> </select> <input id="t2" type="text" /> <input type="button"value="=" onclick ="count()"/> <input id="t3" type="text" /> </form> </body> </html>
default后面的冒号你打成中文的了
default: c=parseInt(a)/parseInt(b); 分号的半角写成全角了哦~ :-->: