JavaScript输出乘法口诀表

  <div id="box">
 
    </div>

    <style>
        * {
            margin: 0;
            padding: 0;
        }
 
        table {
            /* border: 1px solid #222; */
            border-collapse: collapse;
            margin: 10px auto;
        }
 
        td {
            border: 1px solid #222;
            padding: 20px;
        }
 
        #box {
            width: 1000px;
            height: 1000px;
            border: 1px solid red;
            margin: 100px;
        }
    </style>

 <script>
        // 九九乘法口诀表
 
        let str = '<table>'
        //外层循环控制行数
        for (let i = 1; i <= 9; i++) {
            str += '<tr>'
            //内层循环控制td的个数
            for (let j = 1; j <= i; j++) {
                str += `<td>
                           ${j}x${i}=${j*i}
                        
                        
                        </td>`
            }
            str += '</tr>'
        }
        str += '</table>'
        // console.log(str);
        document.write(str);
        document.querySelector('#box').innerHTML = str;
    </script>