网页计算器

2021-11-28 23:02:02 作者：互联网
<!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>Document</title>
</head>
<style>
    * {
        margin: 0;
        padding: 0;
    }
    
    .box {
        width: 380px;
        height: 500px;
        margin: 0 auto;
        margin-top: 100px;
        border-radius: 5px;
        background: rgba(177, 165, 165, 0.58);
        border: 3px solid rgba(0, 0, 0, 0.20);
    }
    
    table {
        margin-top: 20px;
        margin-left: 30px;
        border-spacing: 20px
    }
    
    table td {
        width: 50px;
        height: 40px;
        border: 1px solid rgb(0, 0, 0);
        border-radius: 5px;
        text-align: center;
    }
    
    table input {
        border-radius: 5px;
        width: 50px;
        height: 40px;
        outline: none;
    }
    
    .top {
        width: 330px;
        height: 50px;
        margin-left: 15px;
        margin-top: 50px;
        border-radius: 10px;
        text-align: right;
        background-color: rgb(167, 166, 161);
    }
</style>

<body>
    <div class="box">
        <div>
            <input type="text" id="content" disabled="disabled" class="top">
        </div>
        <div class="contain">
            <table>

                <!--add, subtract, multiply divide delete 加 减 乘 除 删除-->
                <tr>
                    <td><input type="button" value="CE" id="clear" οnclick="appContent(this)"></td>
                    <td><input type="button" value="+" id="add" οnclick="appContent(this)"></td>
                    <td><input type="button" value="-" id="subtract" οnclick="appContent(this)"></td>
                    <td><input type="button" value="DEL" id="delect" οnclick="appContent(this)"></td>
                </tr>
                <tr>
                    <td><input type="button" value="7" id="number7" οnclick="appContent(this)"></td>
                    <td><input type="button" value="8" id="number8" οnclick="appContent(this)"></td>
                    <td><input type="button" value="9" id="number9" οnclick="appContent(this)"></td>
                    <td><input type="button" value="*" id="multiply" οnclick="appContent(this)"></td>
                </tr>
                <tr>
                    <td><input type="button" value="4" id="number4" οnclick="appContent(this)"></td>
                    <td><input type="button" value="5" id="number5" οnclick="appContent(this)"></td>
                    <td><input type="button" value="6" id="number6" οnclick="appContent(this)"></td>
                    <td><input type="button" value="/" id="divide" οnclick="appContent(this)"></td>
                </tr>
                <tr>
                    <td><input type="button" value="1" id="number1" οnclick="appContent(this)"></td>
                    <td><input type="button" value="2" id="number2" οnclick="appContent(this)"></td>
                    <td><input type="button" value="3" id="number3" οnclick="appContent(this)"></td>
                    <td><input type="button" value="." id="point" οnclick="appContent(this)"></td>
                </tr>
                <tr>
                    <td><input type="button" value="(" id="leftbracket" οnclick="appContent(this)"></td>
                    <td><input type="button" value="0" id="number0" οnclick="appContent(this)"></td>
                    <td><input type="button" value=")" id="rightbracket" οnclick="appContent(this)"></td>
                    <td><input type="button" value="=" id="equal" οnclick="appContent(this)"></td>

                </tr>
            </table>
        </div>
    </div>
</body>

<script>
    function appContent(self) {
        var content = document.getElementById('content');
        if (self.value != "CE" && self.value != "DEL" && self.value != "=") {
            content.value += self.value;
        } else if (self.value == "CE") {
            //清空
            content.value = "";
        } else if (self.value == "DEL") {
            //删除：截取除最后一个字符串 substring
            content.value = content.value.substring(0, content.value.length - 1);
        } else if (self.value == "=") {
            //判等
            var resultText = calculate(content.value);
            content.value = content.value + "=" + resultText;
        }
    }

    function calculate(content) {
        var index = content.lastIndexOf("(");
        if (index > -1) {
            var endIndex = content.indexOf(")", index);
            if (endIndex > -1) {
                var result = calculate(content.substring(index + 1, endIndex));
                return calculate(content.substring(0, index) + ("" + result) + content.substring(endIndex + 1))
            }
        }
        index = content.indexOf("+");
        if (index > -1) {
            return calculate(content.substring(0, index)) + calculate(content.substring(index + 1));
        }
        index = content.lastIndexOf("-");
        if (index > -1) {
            return calculate(content.substring(0, index)) - calculate(content.substring(index + 1));
        }
        index = content.lastIndexOf("*");
        if (index > -1) {
            return calculate(content.substring(0, index)) * calculate(content.substring(index + 1));
        }
        index = content.lastIndexOf("/");
        if (index > -1) {
            return calculate(content.substring(0, index)) / calculate(content.substring(index + 1));
        }
        if ("" == content) {
            return 0;
        } else {
            return content - 1 + 1;
        }
    }
</script>

</html>
标签：index,网页,calculate,self,value,content,substring,计算器
来源： https://blog.csdn.net/m0_51443493/article/details/121599787