JS实现简易计算器（input表单）

news2024/10/3 0:30:34

实现效果:
请添加图片描述
代码：

<!DOCTYPE html>
<html>
    <head>
        <meta charset="utf-8">
    </head>
    <body>
        <p>整数1:<input type="text" id="num1"></p>
        <p>整数2:<input type="text" id="num2"></p>
        <p>
            <input type="button" value="相加" onclick="addJia()">
            <input type="button" value="相减" onclick="addJian()">
            <input type="button" value="相乘" onclick="addChen()">
            <input type="button" value="相除" onclick="addChu()">
        </p>
        <p>结果:<input id="result" type="text"></p>
        <script>
            // 加
            function addJia() {
                var num1 = document.getElementById('num1').value;
                var num2 = document.getElementById('num2').value;
                if (num1 == '' || num2 == '') {
                    alert('请输入数字！')
                    return false;
                }
                document.getElementById('result').value = parseInt(num1) + parseInt(num2);
            }

            // 减
            function addJian() {
                var num1 = document.getElementById('num1').value;
                var num2 = document.getElementById('num2').value;
                if (num1 == '' || num2 == '') {
                    alert('请输入数字！')
                    return false;
                }
                document.getElementById('result').value = parseInt(num1) - parseInt(num2);
            }

            // 乘
            function addChen() {
                var num1 = document.getElementById('num1').value;
                var num2 = document.getElementById('num2').value;
                if (num1 == '' || num2 == '') {
                    alert('请输入数字！')
                    return false;
                }
                document.getElementById('result').value = parseInt(num1) * parseInt(num2);
            }

            // 除
            function addChu() {
                var num1 = document.getElementById('num1').value;
                var num2 = document.getElementById('num2').value;
                if (num1 == '' || num2 == '') {
                    alert('请输入数字！')
                    return false;
                }
                if (num2 == '0') {
                    alert('除数不能为0')
                    return false;
                }
                document.getElementById('result').value = parseInt(num1) / parseInt(num2);
            }
        </script>
    </body>
</html>