这里有新鲜出炉的 Javascript 教程,程序狗速度看过来!
Javascript 是一种由 Netscape 的 LiveScript 发展而来的原型化继承的基于对象的动态类型的区分大小写的客户端脚本语言,主要目的是为了解决服务器端语言,比如 Perl,遗留的速度问题,为客户提供更流畅的浏览效果。
这篇文章主要介绍了 JavaScript 如何编写简单的计算器,功能很简单,可以实现加减乘除功能,感兴趣的小伙伴们可以参考一下
本文实例讲述了 JavaScript 编写简单计算器的代码。分享给大家供大家参考。具体如下: 运行效果截图如下:
具体代码如下
- <!DOCTYPE html>
- <html lang="en">
- <head>
- <meta charset="utf-8">
- <title>计算器</title>
- <style>
- /*Basic reset*/
- *{
- margin:0;
- padding:0;
- box-sizing: border-box;
- font: 14px Arial,sans-serif;
- }
- html{
- height:100%;
- background-color:lightslategrey;
- }
- #calculator{
- margin: 15px auto;
- width:330px;
- height:400px;
- border: 1px solid lightgray;
- background-color:darkgrey;
- padding:15px;
- }
- /*LOGO*/
- .LOGO{
- height:20px;
- }
- .LOGO .name{
- float:left;
- line-height:30px;
- }
- .LOGO .verson{
- float:right;
- line-height:30px;
- }
- /*screen*/
- #shuRu{
- margin-top:15px;
- }
- .screen{
- margin-top:5px;
- width:300px;
- height:40px;
- text-align: right;
- padding-right:10px;
- font-size:20px;
- }
- #keys{
- border:1px solid lightgray;
- height:223px;
- margin-top:25px;
- padding:8px;
- }
- #keys .last{
- margin-right:0px;
- }
- .footer{
- margin-top:20px;
- height:20px;
- }
- .footer .link{
- float:right;
- }
- #keys .buttons{
- float:left;
- width: 42px;
- height: 36px;
- text-align:center;
- background-color:lightgray;
- margin: 0 17px 20px 0;
- }
- </style>
- </head>
- <body>
- <div id="calculator">
- <div class="LOGO">
- <span class="name">简单的计算器</span>
- <span class="verson">@walker</span>
- </div>
- <div id="shuRu">
- <!--screen输入栏-->
- <div class="screen">
- <input type="text" id="screenName" name="screenName" class="screen">
- </div>
- </div>
- <div id="keys">
- <!-- j -->
- <!--第一排-->
- <input type="button" id="7" onclick="jsq(this.id)" value="7" class="buttons">
- <input type="button" id="8" onclick="jsq(this.id)" value="8" class="buttons">
- <input type="button" id="9" onclick="jsq(this.id)" value="9" class="buttons">
- <input type="button" id="Back" onclick="tuiGe()" value="Back" class="buttons">
- <input type="button" id="C" onclick="clearNum()" value="C" class="buttons" style="margin-right:0px">
- <!--第二排-->
- <input type="button" id="4" onclick="jsq(this.id)" value="4" class="buttons">
- <input type="button" id="5" onclick="jsq(this.id)" value="5" class="buttons">
- <input type="button" id="6" onclick="jsq(this.id)" value="6" class="buttons">
- <input type="button" id="*" onclick="jsq(this.id)" value="X" class="buttons">
- <input type="button" id="/" onclick="jsq(this.id)" value="/" class="buttons" style="margin-right:0px">
- <!--第三排-->
- <input type="button" id="1" onclick="jsq(this.id)" value="1" class="buttons">
- <input type="button" id="2" onclick="jsq(this.id)" value="2" class="buttons">
- <input type="button" id="3" onclick="jsq(this.id)" value="3" class="buttons">
- <input type="button" id="+" onclick="jsq(this.id)" value="+" class="buttons">
- <input type="button" id="-" onclick="jsq(this.id)" value="-" class="buttons" style="margin-right:0px">
- <!--第四排-->
- <input type="button" id="0" onclick="jsq(this.id)" value="0" class="buttons">
- <input type="button" id="00" onclick="jsq(this.id)" value="00" class="buttons">
- <input type="button" id="." onclick="jsq(this.id)" value="." class="buttons">
- <input type="button" id="%" onclick="jsq(this.id)" value="%" class="buttons">
- <input type="button" id="eva" onclick="eva()" value="=" class="buttons" style="margin-right:0px">
- </div>
- <div class="footer">
- <span class="aside">欢迎使用JavaScript计算器</span>
- <span class="link">
- <a href="#" title="声明" target="_blank">反馈</a>
- </span>
- </div>
- </div>
- </body>
- </html>
js 代码:
- <script>
- var num = 0; // 定义第一个输入的数据
- function jsq(num) {
- //获取当前输入
- if(num=="%"){
- document.getElementById('screenName').value=Math.round(document.getElementById('screenName').value)/100;
- }else{
- document.getElementById('screenName').value += document.getElementById(num).value;
- }
- }
- function eva() {
- //计算输入结果
- document.getElementById("screenName").value = eval(document.getElementById("screenName").value);
- }
- function clearNum() {
- //清0
- document.getElementById("screenName").value = null;
- document.getElementById("screenName").focus();
- }
- function tuiGe() {
- //退格
- var arr = document.getElementById("screenName");
- arr.value = arr.value.substring(0, arr.value.length - 1);
- }
- </script>
来源: http://www.phperz.com/article/17/0414/268502.html