JavaScript实现把十进制非负整数转换为二进制

╰半橙微兮° 2022-05-21 03:58 192阅读 0赞

![70][]

![70 1][]

<!DOCTYPE html>
    <html>
    <head>
        <meta charset="UTF-8">    
        <title>IFE ECMAScript</title>
    </head>
    <body>        
        <input id="dec-number" type="number" placeholder="输入一个十进制非负整数">
        <button id="trans-btn">转化为二进制</button>
        <p id="result">运算结果</p>
        <script>
    
            function dec2bin(decNumber) {
                try {
                    if (decNumber < 0) {
                        throw "必须为非负整数";
                    }
                } catch (error) {          
                    return "Error:" + error;
                }
                var temp = 0;
                var num = decNumber;
                var arr = new Array();
                while (num > 0) {
                    temp = num % 2;
                    arr.push(temp);
                    num = parseInt(num / 2);
                }
                return arr.reverse().join("");
            }
            
            var btn = document.querySelector("#trans-btn");
            btn.addEventListener("click", function () {
                var aaa = document.getElementById("dec-number").value;
                var res = document.getElementById("result");
                res.innerHTML = dec2bin(aaa);
            });
        </script>
    </body>
    </html>

<!DOCTYPE html>
    <html>
    <head>
        <meta charset="UTF-8">    
        <title>IFE ECMAScript</title>
    </head>
    <body>        
        <input id="dec-number" type="number" placeholder="输入一个十进制非负整数">
        <input id="bin-bit" type="number" placeholder="输入转化后二进制数字位数">
        <button id="trans-btn">转化为二进制</button>
        <p id="result">运算结果</p>
        <script>
    
            function dec2bin(decNumber, binBit) {
                try {
                    if (decNumber < 0) {
                        throw "必须为非负整数";
                    }
                } catch (error) {          
                    return "Error:" + error;
                }
                var temp = 0;
                var num = decNumber;
                var arr = new Array();
                while (num > 0) {
                    temp = num % 2;
                    arr.push(temp);
                    num = parseInt(num / 2);
                }
                var str = arr.reverse().join("");
                var len = str.length;
                if (len > binBit) {
                    console.warn("输入的二进制数字位数太小，按原本的位数显示！");
                    return str;
                }
                else {
                    for (var i = 0; i < binBit-len; i++) {  //注意str.length是动态变化的
                        str = "0" + str;
                    }
                    return str;
                }
            }
           
            var btn = document.querySelector("#trans-btn");
            btn.addEventListener("click", function () {
                var aaa = document.getElementById("dec-number").value;
                var binbit = document.getElementById("bin-bit").value;
                var res = document.getElementById("result");
                res.innerHTML = dec2bin(aaa, binbit);
            });
    
        </script>
    </body>
    </html>

[70]: /images/20220521/46c8f493566e4a2a9652ab1e42f92833.png
[70 1]: /images/20220521/99140b7b5e264408afbd0ad99a866fdb.png