13(switch自定义运算).html

<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title>这是鱼爸爸的网址</title>
		<script type="text/javascript">
			var num = prompt("请输入第一个数字：")*1;
			var ysf = prompt("请输入运算符：例如+");
			var num2 = prompt("请输入第二个数字：")*1;
			switch(ysf){
				case "+":
				var ysf= num+num2;
				document.write(ysf);
				break;
				
				case "-":
				var ysf = num-num2;
				document.write(ysf);
				break;
				
				case "*":
				var ysf = num*num2;
				document.write(ysf);
				break;
				
				case "/":
				var ysf = num/num2;
				document.write(ysf);
				break;
				
				case "%":
				var ysf =num%num2;
				document.write(ysf);
				break;
				
				default:
				document.write("输入错误");
				
			}
		</script>
	</head>
	<body>
	</body>
</html>