var yunSuan = 0;// 运算符号，0-无运算;1-加法;2-减法;3-乘法;4-除法
var change = 0;// 属于运算符后需要清空上一数值
var num1 = 0;// 运算第一个数据
var num2 = 0;// 运算第二个数据
var cunChuValue = 0;// 存储的数值
$(function() {
$(".number").click(function() {// 点击数字触发事件
var num = $(this).attr('name');
var oldValue = $("#jieguo").html();
if (change == 1) {
oldValue = "0";
change = 0;
}
var newValue = "";
if (num == -1) {
oldValue = parseFloat(oldValue);
newValue = oldValue * -1;
} else if (num == ".") {
if (oldValue.indexOf('.') == -1)
newValue = oldValue + ".";
else
newValue = oldValue;
} else {
if (oldValue == 0 && oldValue.indexOf('.') == -1) {
newValue = num;
} else {
newValue = oldValue + num;
}
}
$("#jieguo").html(newValue);
});
$("#qingPing").click(function() {// 点击清屏触发事件
$("#jieguo").html("0");
yunSuan = 0;
change = 0;
num1 = 0;
num2 = 0;
});
$("#tuiGe").click(function() {// 点击退格触发事件
if (change == 1) {
yunSuan = 0;
change = 0;
}
var value = $("#jieguo").html();
if (value.length == 1) {
$("#jieguo").html("0");
} else {
value = value.substr(0, value.length - 1);
$("#jieguo").html(value);
}
});
$(".yunSuan").click(function() {// 点击运算符号触发事件
change = 1;
yuSuan = $(this).attr('name');
var value = $("#jieguo").html();
var dianIndex = value.indexOf(".");
if (dianIndex == value.length) {
value = value.substr(0, value.length - 1);
}
num1 = parseFloat(value);
});
$("#dengYu").click(function() {// 点击等于符号触发事件
var value = $("#jieguo").html();
var dianIndex = value.indexOf(".");
if (dianIndex == value.length) {
value = value.substr(0, value.length - 1);
}
num2 = parseFloat(value);
var sum = 0;
if (yuSuan == 1) {
sum = num1 + num2;
} else if (yuSuan == 2) {
sum = num1 - num2;
} else if (yuSuan == 3) {
sum = num1 * num2;
} else if (yuSuan == 4) {
sum = num1 / num2;
} else if (yuSuan == 0 || num1 == 0 || num2 == 0) {
sum = num1 + num2;
}
var re = /^[0-9]+."#jieguo").html(sum);
change = 1;
yuSuan = 0;
num1 = 0;
num2 = 0;
});
$("#cunChu").click(function() {// 点击存储触发事件
change = 1;
var value = $("#jieguo").html();
var dianIndex = value.indexOf(".");
if (dianIndex == value.length) {
value = value.substr(0, value.length - 1);
}
cunChuValue = parseFloat(value);
});
$("#quCun").click(function() {// 点击取存触发事件
change = 1;
$("#jieguo").html(cunChuValue);
});
$("#qingCun").click(function() {// 点击清存触发事件
change = 1;
cunChuValue = 0;
});
$("#leiCun").click(function() {// 点击累存触发事件
change = 1;
var value = $("#jieguo").html();
var dianIndex = value.indexOf(".");
if (dianIndex == value.length) {
value = value.substr(0, value.length - 1);
}
cunChuValue += parseFloat(value);
});
$("#jiCun").click(function() {// 点击积存触发事件
change = 1;
var value = $("#jieguo").html();
var dianIndex = value.indexOf(".");
if (dianIndex == value.length) {
value = value.substr(0, value.length - 1);
}
if (cunChuValue == 0) {
cunChuValue = parseFloat(value);
} else {
cunChuValue = cunChuValue * parseFloat(value);
}
});
});
// 按键监听
$(document)
.keydown(
function(event) {
// 数字监听
if (((event.keyCode > 47 && event.keyCode < 58)
|| (event.keyCode > 95 && event.keyCode < 106) || (event.keyCode == 190 || event.keyCode == 110))
&& !event.shiftKey) {
keyDownNum(event.keyCode);
}
// "+"监听
if ((event.keyCode == 187 && event.shiftKey)
|| event.keyCode == 107) {
keyDownYuSuan(1);
}
// "-"监听
if ((event.keyCode == 189 && event.shiftKey)
|| event.keyCode == 109) {
keyDownYuSuan(2);
}
// "*"监听
if ((event.keyCode == 56 && event.shiftKey)
|| event.keyCode == 106) {
keyDownYuSuan(3);
}
// "/"监听
if (event.keyCode == 191 || event.keyCode == 111) {
keyDownYuSuan(4);
}
// "="监听
if ((event.keyCode == 187 && !event.shiftKey)
|| event.keyCode == 13) {
$("#dengYu").click();
}
// "回退"监听
if (event.keyCode == 8) {
$("#tuiGe").click();
return false;
}
// "清屏"监听
if (event.keyCode == 27 || event.keyCode == 46
|| (event.keyCode == 110 && event.shiftKey)) {
$("#qingPing").click();
return false;
}
// "存储"监听
if (event.keyCode == 112) {
$("#cunChu").click();
return false;
}
// "取存"监听
if (event.keyCode == 113) {
$("#quCun").click();
return false;
}
// "累存"监听
if (event.keyCode == 114) {
$("#leiCun").click();
return false;
}
// "积存"监听
if (event.keyCode == 115) {
$("#jiCun").click();
return false;
}
// "清存"监听
if (event.keyCode == 117) {
$("#qingCun").click();
return false;
}
});
/**
* 按键触发运算符 value 1-'+' 2-'-' 3-'*' 4-'/'
*/
function keyDownYuSuan(value) {
change = 1;
yuSuan = value;
var value = $("#jieguo").html();
var dianIndex = value.indexOf(".");
if (dianIndex == value.length) {
value = value.substr(0, value.length - 1);
}
num1 = parseFloat(value);
}
/**
* 按键触发数字 code ASCLL码
*/
function keyDownNum(code) {
var number = 0;
if (code == 48 || code == 96) {// "0"监听
number = 0;
}
if (code == 49 || code == 97) {// "1"监听
number = 1;
}
if (code == 50 || code == 98) {// "2"监听
number = 2;
}
if (code == 51 || code == 99) {// "3"监听
number = 3;
}
if (code == 52 || code == 100) {// "4"监听
number = 4;
}
if (code == 53 || code == 101) {// "5"监听
number = 5;
}
if (code == 54 || code == 102) {// "6"监听
number = 6;
}
if (code == 55 || code == 103) {// "7"监听
number = 7;
}
if (code == 56 || code == 104) {// "8"监听
number = 8;
}
if (code == 57 || code == 105) {// "9"监听
number = 9;
}
if (code == 190 || code == 110) {// "."监听
number = ".";
}
var num = number;
var oldValue = $("#jieguo").html();
if (change == 1) {
oldValue = "0";
change = 0;
}
var newValue = "";
if (num == -1) {
oldValue = parseFloat(oldValue);
newValue = oldValue * -1;
} else if (num == ".") {
if (oldValue.indexOf('.') == -1)
newValue = oldValue + ".";
else
newValue = oldValue;
} else {
if (oldValue == 0 && oldValue.indexOf('.') == -1) {
newValue = num;
} else {
newValue = oldValue + num;
}
}
$("#jieguo").html(newValue);
} 

<%@ page language="java" contentType="text/html; charset=UTF-"
pageEncoding="UTF-"%>
<!DOCTYPE html>
<html>
<head>
<meta charset=" utf-">
<title>简易计算器</title>
<jsp:include page="inc/easyui.jsp"></jsp:include>
<style type="text/css">
button {
font-size: px;
font-weight: bold;
width: px;
}
</style>
<script type="text/javascript" src="/UploadFiles/2021-04-02/js.js">

计算器样式布局时借鉴别人的，但是代码均是本人自己写的，由于时间原因没有来得及测试，各位大侠在使用过程中发现有bug欢迎提出，共同学习进步，谢谢。