javascript - 如何在javascript中添加列

Question

    function answer(){
            var u='';
            var num1 = document.getElementById('num1').value;
            var total = num1 * num1;
            for(var x=1; x<=num1;x++){
                u=u+x;
                for(var y = u ; y<=num1; y++){
                }
            }
            console.log(u);
        }

<input type="text" id="num1" name="">
    <button type="submit" onclick="answer()">Answer</button>

帮助如何使用 for 循环添加列对不起，我打扰了你

我的示例问题如果用户输入 3 输出变为

1 2 3 
4 5 6
7 8 9

标签： javascripthtml

Answer 1

for您需要在嵌套循环中执行大部分操作。

function answer() {
    var num1 = document.getElementById('num1').value;
    for (var x = 1; x <= num1; x++) {
        var u = '';
        for (var y = 1; y <= num1; y++) {
            u = u + ((x-1) * num1 + y) + ' ';
        }
        console.log(u);
    }
}

<input type="text" id="num1" name="">
<button type="submit" onclick="answer()">Answer</button>