简单计算器

Justacoder

2015-09-12

	<!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>
	<script>
	var initData="";//保存初始字符串
	var num1=0;
	var num2=0;
	var lastop="";//保存最后一个操作符
	//获取数字
	function getNum(num){
	initData += num;
	showData(initData);
	}
	//获得操作符
	function getOp(op){
	lastop=op;
	//保存第一个数
	num1=parseFloat(initData);//转换并保存
	//重新初始化
	initData="";
	}

	//获得结果
	function getResult(){
	//第一个数，已保存
	//第二个数
	num2=parseFloat(initData);
	//符号lastop
	//计算
	var result =calc(num1,num2,lastop);
	//显示结果
	showData(result);
	}
	function calc(num1,num2,op){
	var result=0;
	switch(op){
	case'+':result= num1 + num2;break;
	case'-':result= num1 - num2;break;
	case'':result= num1 num2;break;
	case'%':result= num1 % num2;break;
	case'/':if(num2==0)return;
	else result =num1/num2;break;

	}
	return result;
	}
	//显示数据的方法
	function showData(data){
	document.getElementById("result").value=data;
	}
	//取相反数
	function getOpp(){
	initData=0-parseFloat(initData);
	showData(initData);
	}
	//清除数据
	function getDle(){
	result=0;
	num1=0;
	num2=0;
	lastop=0;
	initData="";
	showData(0);
	}
	function getRe(){
	var sc=initData.substring(0,initData.length-1);
	initData=sc;
	showData(sc);
	}
	</script>
	</head>

	<body>
	<form id="form1" name="form1" method="post" action="">
	<table width="476" height="217" border="1" align="center">
	<tr>
	<th colspan="3" scope="col"><label for="num"></label>
	<input type="text" name="num" id="result" value="" /></th>
	<th scope="col"><input type="button" name="el" id="el" value=" C " onclick="getDle()"/></th>
	<th scope="col" align="center"><input type="button" name="el" id="tl" value=" CE " onclick="getRe()"/></th>
	</tr>
	<tr>
	<td align="center"><input type="button" name="z" id="num7" value=" 7 " onclick="getNum('7')"/></td>
	<td align="center"><input type="button" name="z" id="num8" value=" 8 " onclick="getNum('8')" /></td>
	<td align="center"><input type="button" name="z" id="num9" value=" 9 " onclick="getNum('9')" /></td>
	<td align="center"><input type="button" name="el" id="tl" value=" +/- " onclick="getOpp()" /></td>
	<td align="center"><input type="button" name="el" id="fl" value=" % " onclick="getOp('%')"/></td>
	</tr>
	<tr>
	<td align="center"><input type="button" name="z" id="num6" value=" 6 " onclick="getNum('6')"/></td>
	<td align="center"><input type="button" name="z" id="num5" value=" 5 " onclick="getNum('5')" /></td>
	<td align="center"><input type="button" name="z" id="num4" value=" 4 " onclick="getNum('4')" /></td>
	<td align="center"><input type="button" name="el" id="ffl" value=" + " onclick="getOp('+')" /></td>
	<td align="center"><input type="button" name="el" id="sl" value=" - " onclick="getOp('-')" /></td>
	</tr>
	<tr>
	<td align="center"><input type="button" name="one" id="num1" value=" 1 " onclick="getNum('1')"/></td>
	<td align="center"><input type="button" name="z" id="num2" value=" 2 " onclick="getNum('2')"/></td>
	<td align="center"><input type="button" name="z" id="num3" value=" 3 " onclick="getNum('3')" /></td>
	<td align="center"><input type="button" name="el" id="sl" value=" * " onclick="getOp('*')"/></td>
	<td align="center"><input type="button" name="el" id="eel" value=" / " onclick="getOp('/')"/></td>
	</tr>
	<tr>
	<td align="center"><input type="button" name="z" id="num0" value=" 0 " onclick="getNum('0')"/></td>
	<td align="center"><input type="button" name="z" id="ten" value=" . " onclick="getNum('.')" /></td>
	<td> </td>
	<td align="center"><input type="button" name="nl" id="nl" value=" = " onclick="getResult()"/></td>
	<td align="center"><input type="button" name="el" id="tl" value="返回" onclick="getDle()" /></td>
	</tr>
	</table>
	</form>
	</body>
	</html>