最新js做的一个简单的计算器
javascript代码实现简易计算器
javascript代码实现简易计算器本⽂实例为⼤家分享了javascript实现简易计算器的具体代码，供⼤家参考，具体内容如下编辑了⼏个⼩时研发了⼀个简易好理解的计算器。
不停改Bug，终于改好了。
这是样式这是Css部分<style>#box {background-image: linear-gradient(120deg, #84fab0 0%, #8fd3f4 100%);width: 500px;height: 420px;margin: auto;margin-top: 200px;position: relative;}.reckon {width: 280px;height: 200px;background-image: linear-gradient(120deg, #d4fc79 0%, #96e6a1 100%);;position: absolute;top: 100px;left: 100px;border: 5px solid #2a2b2c}#input1 {background-image: linear-gradient(to top, #cfd9df 0%, #e2ebf0 100%);border: none;width: 220px;height: 8px;float: right;margin-top: 10px;margin-right: 20px;outline: none;padding: 10px}ul li {float: left;list-style: none;margin: 4px 2px;border-radius: 3px;background-image: linear-gradient(120deg, #a1c4fd 0%, #c2e9fb 100%);box-shadow: 2px 2px #ccc;color: #fff;font-weight: "楷体";width: 50px;height: 30px;text-align: center;line-height: 30px;}ul {margin-top: 5px;}ul li:hover {opacity: 0.7;}</style>这是HTML部分<div id="box"><div class="reckon" id="reckon"><input type="text" id="input1"><ul><li class="num">7</li><li class="num">8</li><li class="num">9</li><li class="opcr">+</li><li class="num">4</li><li class="num">5</li><li class="num">6</li><li class="opcr">- </li><li class="num">1</li><li class="num">2</li><li class="num">3</li><li class="opcr">*</li><li class="num">0</li><li id="returnZero">C</li><li id="resule">=</li><li class="opcr">/</li></ul></div></div>/* 定义两个标签来存放符号跟第⼀个值*/<input type="text" id="text1" style="display:none"><input type="text" id="per" style="display:none">html部分的话就是吧所有数字定义为⼀个class名字，把所有运算符号定义为⼀个class 以及定义两个input来存放运算符<script>lis = document.querySelectorAll("#box ul .num")//获取所有的数字opcr = document.querySelectorAll("#box ul .opcr")//获取运算符for (var i = 0; i < lis.length; i++) { //遍历所有的数字lis[i].onclick = function () {input1.value += parseInt(this.innerHTML)//点击input1显⽰}}//遍历所有的运算符for (let i = 0; i < opcr.length; i++) {opcr[i].onclick = function () {if (text1.value == "") {//当存放第⼀个值为空时候text1.value = input1.value//存放第⼀个值input1.value = "" //input框⾥的值为空per.value = this.innerHTML; //存放符号的值为空} else {text1.value = eval(text1.value + per.value + input1.value)//不是空的时候计算per.value = this.innerHTML;//存放符号的值为点击的值input1.value = ""//input框⾥的值为空}}}//等于resule.onclick = function () {input1.value = eval(text1.value + per.value + input1.value)//计算⾥⾯的值 per.value = "" //清空存放per的值text1.value = ""//input框⾥的值为空}//点击清空所有returnZero.onclick = function () {input1.value = ""per.value = ""text1.value = ""}</script>完整部分<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"> <meta http-equiv="X-UA-Compatible" content="ie=edge"><title>简易计算器</title><style>#box {background-image: linear-gradient(120deg, #84fab0 0%, #8fd3f4 100%); width: 500px;height: 420px;margin: auto;margin-top: 200px;position: relative;}.reckon {width: 280px;height: 200px;background-image: linear-gradient(120deg, #d4fc79 0%, #96e6a1 100%); ;position: absolute;top: 100px;left: 100px;border: 5px solid #2a2b2c}#input1 {background-image: linear-gradient(to top, #cfd9df 0%, #e2ebf0 100%);border: none;width: 220px;height: 8px;float: right;margin-top: 10px;margin-right: 20px;outline: none;padding: 10px}ul li {float: left;list-style: none;margin: 4px 2px;border-radius: 3px;background-image: linear-gradient(120deg, #a1c4fd 0%, #c2e9fb 100%); box-shadow: 2px 2px #ccc;color: #fff;font-weight: "楷体";width: 50px;height: 30px;text-align: center;line-height: 30px;}ul {margin-top: 5px;}opacity: 0.7;}</style></head><body><div id="box"><div class="reckon" id="reckon"><input type="text" id="input1"><ul><li class="num">7</li><li class="num">8</li><li class="num">9</li><li class="opcr">+</li><li class="num">4</li><li class="num">5</li><li class="num">6</li><li class="opcr">- </li><li class="num">1</li><li class="num">2</li><li class="num">3</li><li class="opcr">*</li><li class="num">0</li><li id="returnZero">C</li><li id="resule">=</li><li class="opcr">/</li></ul></div></div><input type="text" id="text1" style="display:block"><input type="text" id="per" style="display:block"><script>lis = document.querySelectorAll("#box ul .num")//获取所有的数字opcr = document.querySelectorAll("#box ul .opcr")//获取+——*/for (var i = 0; i < lis.length; i++) { //遍历所有的数字lis[i].onclick = function () {input1.value += parseInt(this.innerHTML)//点击input1显⽰}}//遍历所有的+——*/for (let i = 0; i < opcr.length; i++) {opcr[i].onclick = function () {if (text1.value == "") {//当存放第⼀个值为空时候text1.value = input1.value//存放第⼀个值input1.value = "" //input框⾥的值为空per.value = this.innerHTML; //存放符号的值为空} else {text1.value = eval(text1.value + per.value + input1.value)//不是空的时候计算值 per.value = this.innerHTML;//存放符号的值为点击的值input1.value = ""//input框⾥的值为空}}}//等于resule.onclick = function () {input1.value = eval(text1.value + per.value + input1.value)//计算⾥⾯的值per.value = "" //清空存放per的值text1.value = ""//input框⾥的值为空}//点击清空所有returnZero.onclick = function () {input1.value = ""per.value = ""text1.value = ""}</script></html>以上就是本⽂的全部内容，希望对⼤家的学习有所帮助，也希望⼤家多多⽀持。
JS实现简易计算器的7种方法
JS实现简易计算器的7种⽅法先放图（好吧⽐较挫）⽅法⼀：最容易版<!DOCTYPE html><html lang="zh-CN"><head><meta charset="UTF-8" /><title>简易计算器</title><style>body {background-color: #eee;}#calculator {margin: 100px 0 0 150px;}</style></head><body><!-- 简易计算器 --><div id="calculator"><p><input type="text" class="formerInput" value="1" /><span class="sign">+</span><input type="text" class="laterInput" value="1" /><span>=</span><span class="resultOutput">2</span></p><p><input type="button" value="+" onclick="addHandler();" /><input type="button" value="-" onclick="subtractHandler();" /><input type="button" value="×" onclick="multiplyHandler();" /><input type="button" value="÷" onclick="divideHandler();" /></p></div><script>// 获取元素var calculator = document.querySelector('#calculator');var formerInput = calculator.querySelector('.formerInput');var laterInput = calculator.querySelector('.laterInput');var sign = calculator.querySelector('.sign');var resultOutput = calculator.querySelector('.resultOutput');// 加function addHandler() {sign.innerHTML = '+';resultOutput.innerHTML = +formerInput.value + +laterInput.value;}// 减function subtractHandler() {sign.innerHTML = '-';resultOutput.innerHTML = formerInput.value - laterInput.value;}// 乘function multiplyHandler() {sign.innerHTML = '×';resultOutput.innerHTML = formerInput.value * laterInput.value;}// 除function divideHandler() {sign.innerHTML = '÷';resultOutput.innerHTML = formerInput.value / laterInput.value;}</script></body></html>⽅法⼆：结构和⾏为分离<!DOCTYPE html><html lang="zh-CN"><head><meta charset="UTF-8" /><title>简易计算器</title>#calculator {margin: 100px 0 0 150px;}</style></head><body><!-- 简易计算器 --><div id="calculator"><p><input type="text" class="formerInput" value="1" /><span class="sign">+</span><input type="text" class="laterInput" value="1" /><span>=</span><span class="resultOutput">2</span></p><p><input type="button" value="+" onclick="addHandler();" /><input type="button" value="-" onclick="subtractHandler();" /><input type="button" value="×" onclick="multiplyHandler();" /><input type="button" value="÷" onclick="divideHandler();" /></p></div><script>// 获取元素var calculator = document.querySelector('#calculator');var formerInput = calculator.querySelector('.formerInput');var laterInput = calculator.querySelector('.laterInput');var sign = calculator.querySelector('.sign');var resultOutput = calculator.querySelector('.resultOutput');var btns = calculator.querySelectorAll('.btn');// 绑定事件// +btns[0].onclick = addHandler;// -btns[1].onclick = subtractHandler;// ×btns[2].onclick = multiplyHandler;// ÷btns[3].onclick = divideHandler;// 加function addHandler() {sign.innerHTML = '+';resultOutput.innerHTML = +formerInput.value + +laterInput.value; }// 减function subtractHandler() {sign.innerHTML = '-';resultOutput.innerHTML = formerInput.value - laterInput.value;}// 乘function multiplyHandler() {sign.innerHTML = '×';resultOutput.innerHTML = formerInput.value * laterInput.value;}// 除function divideHandler() {sign.innerHTML = '÷';resultOutput.innerHTML = formerInput.value / laterInput.value;}</script></body></html>⽅法三：循环绑定事件<!DOCTYPE html><html lang="zh-CN"><head><meta charset="UTF-8" /><title>简易计算器</title><style>body {background-color: #eee;}#calculator {margin: 100px 0 0 150px;<!-- 简易计算器 --><div id="calculator"><p><input type="text" class="formerInput" value="1" /><span class="sign">+</span><input type="text" class="laterInput" value="1" /><span>=</span><span class="resultOutput">2</span></p><p><input type="button" value="+" onclick="addHandler();" /><input type="button" value="-" onclick="subtractHandler();" /><input type="button" value="×" onclick="multiplyHandler();" /><input type="button" value="÷" onclick="divideHandler();" /></p></div><script>// 获取元素var calculator = document.querySelector('#calculator');var formerInput = calculator.querySelector('.formerInput');var laterInput = calculator.querySelector('.laterInput');var sign = calculator.querySelector('.sign');var resultOutput = calculator.querySelector('.resultOutput');var btns = calculator.querySelectorAll('.btn');// 绑定事件for (var i = 0; i < btns.length; i++) {btns[i].onclick = function () {switch (this.title) {case 'add':addHandler();break;case 'subtract':subtractHandler();break;case 'multiply':multiplyHandler();break;case 'divide':divideHandler();break;}};}// 加function addHandler() {sign.innerHTML = '+';resultOutput.innerHTML = +formerInput.value + +laterInput.value; }// 减function subtractHandler() {sign.innerHTML = '-';resultOutput.innerHTML = formerInput.value - laterInput.value;}// 乘function multiplyHandler() {sign.innerHTML = '×';resultOutput.innerHTML = formerInput.value * laterInput.value;}// 除function divideHandler() {sign.innerHTML = '÷';resultOutput.innerHTML = formerInput.value / laterInput.value;}</script></body></html>⽅法四：提取函数<!DOCTYPE html><html lang="zh-CN"><head><meta charset="UTF-8" /><title>简易计算器</title><style>body {margin: 100px 0 0 150px;}</style></head><body><!-- 简易计算器 --><div id="calculator"><p><input type="text" class="formerInput" value="1" /><span class="sign">+</span><input type="text" class="laterInput" value="1" /><span>=</span><span class="resultOutput">2</span></p><p><input type="button" value="+" class="btn" title="add" /><input type="button" value="-" class="btn" title="subtract" /> <input type="button" value="×" class="btn" title="multiply" /> <input type="button" value="÷" class="btn" title="divide" /> </p></div><script>// 获取元素var calculator = document.querySelector('#calculator');var formerInput = calculator.querySelector('.formerInput');var laterInput = calculator.querySelector('.laterInput');var sign = calculator.querySelector('.sign');var resultOutput = calculator.querySelector('.resultOutput');var btns = calculator.querySelectorAll('.btn');// 绑定事件each(btns, function (index, elem ) {elem.onclick = function () {switch (this.title) {case 'add':addHandler();break;case 'subtract':subtractHandler();break;case 'multiply':multiplyHandler();break;case 'divide':divideHandler();break;}};});// 遍历function each(array, fn) {for (var i = 0; i < array.length; i++) {fn(i, array[i]);}}// 更新符号function updateSign(symbol) {sign.innerHTML = symbol;}// 加法function add(num1, num2) {return +num1 + +num2;}// 减法function subtract(num1, num2) {return num1 - num2;}// 乘法function multiply(num1, num2) {return num1 * num2;}// 除法function divide(num1, num2) {return num1 / num2;}// 输出结果}// 加function addHandler() {// sign.innerHTML = '+';updateSign('+');outputResult(add(formerInput.value, laterInput.value));}// 减function subtractHandler() {updateSign('-');outputResult(subtract(formerInput.value, laterInput.value)); }// 乘function multiplyHandler() {updateSign('×');outputResult(multiply(formerInput.value, laterInput.value)); }// 除function divideHandler() {updateSign('÷');outputResult(divide(formerInput.value, laterInput.value)); }</script></body></html>⽅法五：管理代码(找到组织)<!DOCTYPE html><html lang="zh-CN"><head><meta charset="UTF-8" /><title>简易计算器</title><style>body {background-color: #eee;}#calculator {margin: 100px 0 0 150px;}</style></head><body><!-- 简易计算器 --><div id="calculator"><p><input type="text" class="formerInput" value="1" /><span class="sign">+</span><input type="text" class="laterInput" value="1" /><span>=</span><span class="resultOutput">2</span></p><p><input type="button" value="+" class="btn" title="add" /><input type="button" value="-" class="btn" title="subtract" /> <input type="button" value="×" class="btn" title="multiply" /> <input type="button" value="÷" class="btn" title="divide" /> </p></div><script>// 获取元素var wrapElem = document.querySelector('#calculator');var calculatorElem = {formerInput: wrapElem.querySelector('.formerInput'),laterInput: wrapElem.querySelector('.laterInput'),sign: wrapElem.querySelector('.sign'),resultOutput: wrapElem.querySelector('.resultOutput'), btns: wrapElem.querySelectorAll('.btn')};// 绑定事件each(calculatorElem.btns, function (index, elem ) {elem.onclick = function () {switch (this.title) {case 'add':addHandler();break;case 'subtract':multiplyHandler();break;case 'divide':divideHandler();break;}};});// 遍历function each(array, fn) {for (var i = 0; i < array.length; i++) {fn(i, array[i]);}}// 更新符号function updateSign(symbol) {calculatorElem.sign.innerHTML = symbol;}var operation = {add: function(num1, num2) {return +num1 + +num2;},subtract: function(num1, num2) {return num1 - num2;},multiply: function(num1, num2) {return num1 * num2;},divide: function(num1, num2) {return num1 / num2;}};// 输出结果function outputResult(result) {calculatorElem.resultOutput.innerHTML = result;}// 加function addHandler() {// sign.innerHTML = '+';updateSign('+');outputResult(operation.add(calculatorElem.formerInput.value, terInput.value));}// 减function subtractHandler() {updateSign('-');outputResult(operation.subtract(calculatorElem.formerInput.value, terInput.value)); }// 乘function multiplyHandler() {updateSign('×');outputResult(operation.multiply(calculatorElem.formerInput.value, terInput.value)); }// 除function divideHandler() {updateSign('÷');outputResult(operation.divide(calculatorElem.formerInput.value, terInput.value)); }</script></body></html>⽅法六：OCP开放--封闭原则<!DOCTYPE html><html lang="zh-CN"><head><meta charset="UTF-8" /><title>简易计算器</title><style>body {background-color: #eee;}#calculator {margin: 100px 0 0 150px;}</style></head><!-- 简易计算器 --><div id="calculator"><p><input type="text" class="formerInput" value="1" /><span class="sign">+</span><input type="text" class="laterInput" value="1" /><span>=</span><span class="resultOutput">2</span></p><p><input type="button" value="+" class="btn" title="add" /><input type="button" value="-" class="btn" title="subtract" /><input type="button" value="×" class="btn" title="multiply" /><input type="button" value="÷" class="btn" title="divide" /><input type="button" value="%" class="btn" title="mod" /><input type="button" value="^" class="btn" title="power" /><!-- <input type="button" value="1/x" class="btn" title="invert" /> --></p></div><script>// 获取元素var wrapElem = document.querySelector('#calculator');var calculatorElem = {formerInput: wrapElem.querySelector('.formerInput'),laterInput: wrapElem.querySelector('.laterInput'),sign: wrapElem.querySelector('.sign'),resultOutput: wrapElem.querySelector('.resultOutput'),btns: wrapElem.querySelectorAll('.btn')};// 绑定事件each(calculatorElem.btns, function (index, elem ) {elem.onclick = function () {updateSign(this.value);outputResult(operate(this.title, calculatorElem.formerInput.value, terInput.value)); };});// 遍历function each(array, fn) {for (var i = 0; i < array.length; i++) {fn(i, array[i]);}}// 更新符号function updateSign(symbol) {calculatorElem.sign.innerHTML = symbol;}// 运算function operate(name, num1, num2) {if (!operation[name]) throw new Error('不存在名为' + name + '的运算⽅法！');return operation[name](num1, num2);}var operation = {add: function(num1, num2) {return +num1 + +num2;},subtract: function(num1, num2) {return num1 - num2;},multiply: function(num1, num2) {return num1 * num2;},divide: function(num1, num2) {return num1 / num2;},addOperation: function (name, fn) {if (!this[name]) {this[name] = fn;}return this;}};operation.addOperation('mod', function (num1, num2) {return num1 % num2;}).addOperation('power', function (base, power) {return Math.pow(base, power);function outputResult(result) {calculatorElem.resultOutput.innerHTML = result;}</script></body></html>⽅法七：模块化<!DOCTYPE html><html lang="zh-CN"><head><meta charset="UTF-8" /><title>简易计算器</title><style>body {background-color: #eee;}#calculator {margin: 100px 0 0 150px;}</style></head><body><!-- 简易计算器 --><div id="calculator"><p><input type="text" class="formerInput" value="1" /><span class="sign">+</span><input type="text" class="laterInput" value="1" /><span>=</span><span class="resultOutput">2</span></p><p><input type="button" value="+" class="btn" title="add" /><input type="button" value="-" class="btn" title="subtract" /><input type="button" value="×" class="btn" title="multiply" /><input type="button" value="÷" class="btn" title="divide" /><input type="button" value="%" class="btn" title="mod" /><input type="button" value="^" class="btn" title="power" /><input type="button" value="1/x" class="btn" title="invert" /></p></div><script>(function () {// 获取元素var wrapElem = document.querySelector('#calculator');var calculatorElem = {formerInput: wrapElem.querySelector('.formerInput'),laterInput: wrapElem.querySelector('.laterInput'),sign: wrapElem.querySelector('.sign'),resultOutput: wrapElem.querySelector('.resultOutput'),btns: wrapElem.querySelectorAll('.btn')};// 绑定事件each(calculatorElem.btns, function (index, elem ) {elem.onclick = function () {updateSign(this.value);outputResult(operate(this.title, calculatorElem.formerInput.value, terInput.value)); };});// 遍历function each(array, fn) {for (var i = 0; i < array.length; i++) {fn(i, array[i]);}}// 更新符号function updateSign(symbol) {calculatorElem.sign.innerHTML = symbol;}// 运算var operate = (function () {subtract: function(num1, num2) {return num1 - num2;},multiply: function(num1, num2) {return num1 * num2;},divide: function(num1, num2) {return num1 / num2;},addOperation: function (name, fn) {if (!operation[name]) {operation[name] = fn;}return operation;}};function operate(name) {if (!operation[name]) throw new Error('不存在名为' + name + '的运算⽅法！');return operation[name].apply(operation, [].slice.call(arguments, 1, arguments.length)); }operate.addOperation = operation.addOperation;return operate;})();operate.addOperation('mod', function (num1, num2) {return num1 % num2;}).addOperation('power', function (base, power) {return Math.pow(base, power);}).addOperation('invert', function (num) {return 1 / num;});// 输出结果function outputResult(result) {calculatorElem.resultOutput.innerHTML = result;}})();</script></body></html>。
Javascript实现简单计算器实例代码
Javascript实现简单计算器实例代码效果图：刚开始做时没考虑到清零和退格两个功能，嘻嘻，后来加的整体与传统计算器⽐有点⼩瑕疵。
代码：<!DOCTYPE html><html><head><meta charset="utf-8"><title>js简单计算器</title><style type="text/css">*{margin:0px;padding:0px;}input{margin-top:2px;margin-left:2px;width:230px;height:30px;text-align:right;}button{margin-top:2px;margin-left:2px;width:50px;height:50px;}#container{margin-left:1px;border:1px solid #E4E4E4;background:#BBBBBB;width:235px;height:215px;}</style><script>function onLoad(){//加载完毕后光标⾃动对应到输⼊框document.getElementById("input").focus();}//读取按钮的值，传给输⼊框function inputEvent(e){//把val的值改为每个事件的innerHTML值var val=e.innerHTML;//获取input标签var xsval=document.getElementById("input");//标签⾥的value连接每个事件的innerHTML值xsval.value+=val;}//计算出结果function inputOper(){var xsval=document.getElementById("input");xsval.value=eval(document.getElementById("input").value);}//清零function clearNum(){var xsval=document.getElementById("input");xsval.value="";document.getElementById("input").focus();}//退格function backNum(){var arr=document.getElementById("input");arr.value=arr.value.substring(0,arr.value.length-1);}</script></head><body onload="onLoad()"><input id="input" type="text"><div id="container"><div><button onclick="inputEvent(this)">1</button><button onclick="inputEvent(this)">2</button><button onclick="inputEvent(this)">3</button><button onclick="inputEvent(this)">+</button></div><div><button onclick="inputEvent(this)">4</button><button onclick="inputEvent(this)">5</button><button onclick="inputEvent(this)">6</button><button onclick="inputEvent(this)">-</button></div><div><button onclick="inputEvent(this)">7</button><button onclick="inputEvent(this)">8</button><button onclick="inputEvent(this)">9</button><button onclick="inputEvent(this)">*</button></div><div><button onclick="inputEvent(this)">0</button><button onclick="inputEvent(this)">.</button><button onclick="inputOper(this)">=</button><button onclick="inputEvent(this)">/</button></div></div><button onclick="clearNum()">清零</button><button onclick="backNum()">退格</button></body></html>感谢阅读，希望能帮助到⼤家，谢谢⼤家对本站的⽀持！。
超级简易的JS计算器（实现加减乘除）
超级简易的JS计算器（实现加减乘除）<!DOCTYPE html><html><head><meta charset="UTF-8"><title>简单的计算器</title><style>body{margin: 0;}.tab{border: 3px solid black ;border-radius: 2px;border-collapse:collapse;width: 268px;height: 402px;margin: 100px auto;}.tr{height: 67px;width: 268px;border: 3px solid black ;text-align: right;}.tr1{width: 268px;height: 67px;border: 3px solid black ;text-align: center;}.tr2{width: 67px;height: 67px;border: 3px solid black ;text-align: center;}</style><script>var s1 = "";var s2 = "";var s3 = "";var s4 = "";var s5 = "";function view(val){var a = document.getElementById(val);s1 = a.innerHTML;if(s1=="+" || s1=="-" || s1=="*" || s1=="/"){s3 = s1;s1 = "";}if(s3=="+" || s3=="-" || s3=="*" || s3=="/"){add2(s1);}if(s3==""){add1(s1);}}function add1(s1){s2 = s2 + s1;show();}function add2(s1){s4 = s4 + s1;show();}function cal(){switch(s3){case "+":{s5 = (String)((parseFloat(s2)+parseFloat(s4)).toFixed(2));result.innerHTML = s5;break;}case "-":{s5 = (String)((parseFloat(s2)-parseFloat(s4)).toFixed(2));result.innerHTML = s5;break;}case "*":{s5 = (String)((parseFloat(s2)*parseFloat(s4)).toFixed(2));result.innerHTML = s5;break;}case "/":{s5 = (String)((parseFloat(s2)/parseFloat(s4)).toFixed(2));result.innerHTML = s5;break;}}}function show(){var result = document.getElementById("result");result.innerHTML = s2+s3+s4;}</script></head><body><table class="tab"><tr class = "tr2"><td colspan="4">简易计算器</td></tr><tr class="tr"><td id="result" colspan="4"></td></tr><tr ><td id="+" class="tr1" onclick="view('+')">+</td><td id="-" class="tr1" onclick="view('-')">-</td><td id="*" class="tr1" onclick="view('*')">*</td><td id="/" class="tr1" onclick="view('/')">/</td></tr><tr ><td id="7" class="tr1" onclick="view('7')">7</td><td id="8" class="tr1" onclick="view('8')">8</td><td id="9" class="tr1" onclick="view('9')">9</td><td id="0" class="tr1" onclick="view('0')">0</td></tr><tr><td id="4" class="tr1" onclick="view('4')">4</td><td id="5" class="tr1" onclick="view('5')">5</td><td id="6" class="tr1" onclick="view('6')">6</td><td id="." class="tr1" onclick="view('.')">.</td></tr><tr><td id="1" class="tr1" onclick="view('1')">1</td><td id="2" class="tr1" onclick="view('2')">2</td><td id="3" class="tr1" onclick="view('3')">3</td><td id="=" class="tr1" onclick="cal()">=</td></tr></table></body></html>对于这个程序来说，判断的顺序⾮常重要，不然就会把"+"号存在s2，s4中⽽不是s3中。
JavaScript编写的简易计算器
<td>
<input type="button" style="width:40px" value="pi" onclick="cal.totoal.value=Math.PI">
</td>
<td>
<input type="button" style="width:40px" value="E" onclick="cal.total.value=Math.E">
</td>
<td>
<input type="button" style="width:40px" value="7" onclick="addNum('7')">
</td>
<td>
<input type="button" style="width:40px" value="8" onclick="addNum('8')">
preOper=true;
break;
case "asin":
cal.total.value=Math.asin(cal.total.value);
preOper=true;
break;
case "acos":
cal.total.value=Math.acos(cal.total.value);
JavaScript实现简单的四则运算计算器完整实例
JavaScript实现简单的四则运算计算器完整实例本⽂实例讲述了JavaScript实现简单的四则运算计算器。
分享给⼤家供⼤家参考，具体如下：运⾏效果图如下：完整实例代码如下：<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><title>computer</title><script>function compute(){str1=Number(document.getElementById("txt1").value);str2=Number(document.getElementById("txt2").value);comp=document.getElementById("select").value;var result;switch(comp) {case "+":comp=str1+str2;break;case "-":comp=str1-str2;break;case "*":comp=str1*str2;break;case "/":if(str2==0){alert("除数不能为0！");comp='';}else{comp=str1/str2;}break;}document.getElementById("result").value=comp;}</script></head><body><input type="text" id="txt1"/><select name="method" id="select"><option value="+">+</option><option value="-">-</option><option value="*">*</option><option value="/">/</option></select><input type="text" id="txt2"/><input type="button" id="b1" value="等于" onclick="compute()" /><input type="text" id="result"/></body></html>PS：这⾥再为⼤家推荐⼏款计算⼯具供⼤家进⼀步参考借鉴：更多关于JavaScript相关内容感兴趣的读者可查看本站专题：《》、《》、《》、《》、《》、《》及《》希望本⽂所述对⼤家JavaScript程序设计有所帮助。
利用JavaScript写一个简单计算器
利⽤JavaScript写⼀个简单计算器效果如下：参考程序：<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=edge"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>模拟计算器</title><style>button {width: 39px;height: 30px;background-color: rgb(102, 240, 102);}button:hover {background-color: black;color: rgb(255, 249, 237);}button:active {background-color: rgb(79, 72, 72);color: white;}table{background: rgb(192, 248, 109);}</style></head><body><div><table border="1px"><tr style="text-align: center;"><td colspan="4"><input type="text" id="result" ></td></tr><tr><td><button id="le" onclick="getChar('(')">(</button></td><td><button id="rg" onclick="getChar(')')">)</button></td><td><button id="baifen" onclick="getChar('%')">%</button></td> <td><button id="C" onclick="clear1()">C</button></td></tr><tr><td><button id="seven" onclick="getChar('7')">7</button></td> <td><button id="eight" onclick="getChar('8')">8</button></td> <td><button id="nine" onclick="getChar('9')">9</button></td><td><button id="divi" onclick="getChar('/')">/</button></td></tr><tr><td><button id="four" onclick="getChar('4')">4</button></td><td><button id="five" onclick="getChar('5')">5</button></td><td><button id="six" onclick="getChar('6')">6</button></td><td><button id="mul" onclick="getChar('*')">*</button></td></tr><tr><td><button id="one" onclick="getChar('1')">1</button></td><td><button id="two" onclick="getChar('2')">2</button></td><td><button id="three" onclick="getChar('3')">3</button></td> <td><button id="dec" onclick="getChar('-')">-</button></td></tr><tr><td><button id="zero" onclick="getChar('0')">0</button></td><td><button id="point" onclick="getChar('.')">.</button></td><td><button id="=" onclick="getResult()">=</button></td><td><button id="add" onclick="getChar('+')">+</button></td></tr></table></div></body><script>// 点击按键返回按键值function getChar(btnid) {var btns = document.getElementsByTagName("button") switch (btnid) {case '+':setNum('+')break;case '.':setNum('.')break;case '=':setNum('=')break;case '0':setNum('0')break;case '1':setNum('1')break;case '2':setNum('2')break;case '3':setNum('3')break;case '-':setNum('-')break;case '4':setNum('4')break;case '5':setNum('5')break;case '6':setNum('6')break;case '7':setNum('7')break;case '8':setNum('8')break;case '9':setNum('9')break;case '/':setNum('/')break;case '*':setNum('*')break;case '(':setNum('(')break;case ')':setNum(')')break;case '%':setNum('%')break;default:break;}}// 清空显⽰屏function clear1() {document.getElementById("result").value = "" }// 将数值显⽰到显⽰屏function setNum(charCode) {var origin = document.getElementById('result'); origin.value += charCode;origin.innerText = origin.value;}// 计算结果function getResult(){var res=eval(document.getElementById("result").value);// 追加'='setNum('=');// 追加结果setNum(res)}</script></html>备注：在做计算的时候，可以直接使⽤eval这个函数，我们就不⽤⾃⼰⼿动写加减乘除的计算逻辑了，⼤⼤简化了开发例如：var num=eval(‘3+3')则运算结果是num=6eval函数⽤法：语法：eval（参数）,参数是js表达式，为字符串，可以包含变量以及已经存在对象的属性返回值情况：参数类型返回值整数或者函数整数或函数字符串（且是表达式）该字符串表达式的运⾏结果字符串（且是语句或者语句块）执⾏该语句块并返回undefined到此这篇关于利⽤JavaScript写⼀个简单计算器的⽂章就介绍到这了,更多相关JavaScript写简单计算器内容请搜索以前的⽂章或继续浏览下⾯的相关⽂章希望⼤家以后多多⽀持！。
信息技术作业使用JavaScript实现一个简单的计算器程序
信息技术作业使用JavaScript实现一个简单的计算器程序使用JavaScript实现一个简单的计算器程序JavaScript是一种广泛用于网页开发的脚本语言，可以方便地与HTML结合使用。
在本篇文章中，我们将使用JavaScript编写一个简单的计算器程序。
该程序将具备基本的加减乘除功能，以及清零和回退操作。
程序实现的核心是通过JavaScript的事件监听机制，监听用户的点击事件，并根据点击按钮的不同进行相应的处理。
下面是具体的实现步骤：1. 页面布局首先，我们需要在HTML中搭建计算器的基本界面。
可以使用HTML的表格元素来实现计算器的按钮布局，如下所示：```html<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><title>简单计算器</title><script src="calculator.js"></script></head><body><table><tr><td colspan="4"><input type="text" id="result" readonly></td> </tr><tr><td><button onclick="appendNumber(7)">7</button></td><td><button onclick="appendNumber(8)">8</button></td><td><button onclick="appendNumber(9)">9</button></td><td><button onclick="appendOperator('+')">+</button></td> </tr><tr><td><button onclick="appendNumber(4)">4</button></td><td><button onclick="appendNumber(5)">5</button></td><td><button onclick="appendNumber(6)">6</button></td><td><button onclick="appendOperator('-')">-</button></td></tr><tr><td><button onclick="appendNumber(1)">1</button></td> <td><button onclick="appendNumber(2)">2</button></td> <td><button onclick="appendNumber(3)">3</button></td> <td><button onclick="appendOperator('*')">*</button></td> </tr><tr><td><button onclick="appendNumber(0)">0</button></td> <td><button onclick="appendNumber('.')">.</button></td> <td><button onclick="calculate()">=</button></td><td><button onclick="appendOperator('/')">/</button></td> </tr><tr><td colspan="4"><button onclick="clearResult()">清零</button></td></tr><tr><td colspan="4"><button onclick="backspace()">回退</button></td></tr></table></body></html>```在上面的代码中，我们使用`<input>`元素来显示计算结果，使用`<button>`元素来作为按钮，通过调用相应的JavaScript函数来执行对应的操作。
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NewNumber = "yes";
opvalue = '/';
Num(Number1);
}
function SqrtButton() { //开方
Number1 = Math.sqrt(Number1);
NewNumber = "blank";
Num(Number1);
}
function RecipButton() { //倒数
Number1 = 1/Number1;
NewNumber = "blank";
Num(Number1);
}
function NegateButton() { //正负数切换
Number1 = parseFloat(-Number1);
NewNumber = "no";
Num(Number1);
}
function EqualButton() { //等号
js做的一个简单的计算器
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="/1999/xhtml">
}
function ClearCalc() { //清屏
Number1 = "";
Number2 = "";
NewNumber = "blank";
Num("");
}
function CheckNumber(answer) { //读取输入值
if(answer == ".") {
Number = document.calculator.answer.value;
</tr>
<tr>
<td width="23" ><input name="one" type="button" value="1" onClick="CheckNumber('1'); return false;"/></td>
<td width="23" ><input name="two" type="button" value="2" onClick="CheckNumber('2'); return false;"/></td>
}
NewNumber = "yes";
opvalue = '-';
Num(Number1);
}
function MultButton(x) { //乘
if(x == 1) EqualButton();
if(Number2 != "") {
Number1 = parseFloat(Number1) * parseFloat(Number2);
if(Number.indexOf(".") != -1) {
answer = "";
}
}
if(NewNumber == "yes") {
Number2 += answer;
Num(Number2);
}else {
if(NewNumber == "blank") {
Number1 = answer;
var Number1 = ""; //输入第一个数
var Number2 = "";//输入第二个数
var NewNumber = "blank";
var opvalue = "";
function Num(number){
document.calculator.answer.value=number;//输出值
if(opvalue == '+') AddButton(0);
if(opvalue == '-') SubButton(0);
if(opvalue == '*') MultButton(0);
if(opvalue == '/') DivButton(0);
Number2 = "";
opvalue = "";
}
NewNumber = "yes";
opvalue = '*';
Num(Number1);
}
function DivButton(x) { //除
if(x == 1) EqualButton();
if(Number2 != "") {
Number1 = parseFloat(Number1) / parseFloat(Number2);
Number2 = "";
NewNumber = "no";
} else {
Number1 += answer;
}
Num(Number1);
}
}
function AddButton(x) { //加
if(x == 1) EqualButton();
if(Number2 != "") {
Number1 = parseFloat(Number1) + parseFloat(Number2);
}
NewNumber = "yes";
opvalue = '+';
Num(Number1);
}
function SubButton(x) { //减
if(x == 1) EqualButton();
if(Number2 != "") {
Number1 = parseFloat(Number1) - parseFloat(Number2);
}
</script>
<body>
<form name="calculator">
<table height="175" width="161" border="1">
<tr>
<td colspan="5"><input name="answer" type="text" style="width:176px" onchange="CheckNumber(this.value)"/></td>
<head>
&tent-Type" content="text/html; charset=gb2312" />
<title>calculator</title>
</head>
<script language="javascript" type="text/javascript">
<td width="23" ><input name="three" type="button" value="3" onClick="CheckNumber('3'); return false;"/></td>