首页 > > 网页制作 > css >

使用html+css+js实现简易计算器

2018-12-17 10:47:32来源：博客园阅读 ()

使用html+css+js实现简易计算器，

效果图如下：

html代码如下：

 1 <!DOCTYPE html>
 2 <html lang="en">
 3 <head>
 4     <meta charset="UTF-8">
 5     <meta name="viewport" content="width=device-width, initial-scale=1.0">
 6     <meta http-equiv="X-UA-Compatible" content="ie=edge">
 7     <title>calculator</title>
 8     <link rel="stylesheet" type="text/css" href="style.css">
 9     <script type="text/javascript" src="contain.js"></script>
10     <title>Document</title>
11 </head>
12 <body>
13    <div class="calculator">
14     <form name="calculator">
15         <input type="text" id="display" value="">
16             <br>
17         <input type="button" class="btn number txt" value="TYNAM">
18         <input type="button" id="clear" class="btn number" value="AC" onclick="cleardisplay();">
19         <input type="button" class="btn number" value="<-" onclick="del();">
20         <input type="button" class="btn operator" value="/" onclick="get(this.value);">
21             <br>
22         <input type="button" class="btn number" value="7" onclick="get(this.value);">
23         <input type="button" class="btn number" value="8" onclick="get(this.value);">
24         <input type="button" class="btn number" value="9" onclick="get(this.value);">
25         <input type="button" class="btn operator" value="*" onclick="get(this.value);">
26             <br>
27         <input type="button" class="btn number" value="4" onclick="get(this.value);">
28         <input type="button" class="btn number" value="5" onclick="get(this.value);">
29         <input type="button" class="btn number" value="6" onclick="get(this.value);">
30         <input type="button" class="btn operator" value="+" onclick="get(this.value);">
31             <br>
32         <input type="button" class="btn number" value="1" onclick="get(this.value);">
33         <input type="button" class="btn number" value="2" onclick="get(this.value);">
34         <input type="button" class="btn number" value="3" onclick="get(this.value);">
35         <input type="button" class="btn operator" value="-" onclick="get(this.value);">
36             <br>
37         <input type="button" class="btn number" value="0" onclick="get(this.value);">
38         <input type="button" class="btn number" value="." onclick="get(this.value);">
39         <input type="button" class="btn operator equal" value="=" onclick="calculates();">
40     </form>
41    </div> 
42 </body>
43 </html>

CSS代码如下：

 1 * {
 2     border: none;
 3     font-family: 'Open Sans', sans-serif;
 4     margin: 0;
 5     padding: 0;
 6 }
 7 
 8 .calculator {
 9     background-color: #fff;
10     height: 600px;
11     margin: 50px auto;
12     width: 600px;
13 }
14 
15 form {
16     background-color: rgb(75, 70, 71);
17     padding: 5px 1px auto;    
18     width: 245px;
19 }
20 .btn {
21     outline: none;
22     cursor: pointer;
23     font-size: 20px;
24     height: 45px;
25     margin: 5px 0 5px 10px;
26     width: 45px;
27    
28 }
29 .btn:first-child {
30     margin: 5px 0 5px 10px;
31 }
32 
33 #display {
34     outline: none;
35     background-color: #dededc;
36     color: rgb(75, 70, 71);
37     font-size: 40px;
38     height: 47px;
39     text-align: right;
40     width: 224px;
41     margin: 10px 10px auto;
42 }
43 .number {
44     background-color: rgb(143, 140, 140);
45     color: #dededc;
46 }
47 
48 .operator {
49     background-color: rgb(239, 141, 49);
50     color: #ffffff;
51 }
52 
53 .equal{
54     width: 105px;
55 }
56 
57 .txt{
58     font-size:12px;
59     background: none;
60 }

JS代码如下：

/* display clear */ 
function cleardisplay() {
    document.getElementById("display").value = "";
}

/* del */
function del() {
    var numb = "";
    numb = document.getElementById("display").value;
    for(i=0;i<numb.length;i++)
    {
        document.getElementById("display").value = numb.substring(0,numb.length-1);
        if(numb == '')
        {
            document.getElementById("display").value = '';
        }
    }
} 

/* recebe os valores */
function get(value) {
    document.getElementById("display").value += value; 
} 

/* calcula */
function calculates() {
    var result = 0;
    result = document.getElementById("display").value;
    document.getElementById("display").value = "";
    document.getElementById("display").value = eval(result);
};