Question

尝试创建一个输出给定最大值的乘法表的函数。

我的问题是我有一个数组我需要加入一个字符串，无论我尝试什么，我都无法摆脱每个内部数组项之间的逗号，请帮助我！

这是我的代码：

＆＃13;

var multiplicationTable = function(maxValue) {
  var array = [];
  var maxNum = maxValue ** 2;
  y = 1;
  var pad = ("+--" + "-".repeat(maxNum.toString().length - y.toString().length + 1)).repeat(maxValue) + "\+\n";
  for (var i = 0; i <= maxValue * 2; i++) {
    if (i % 2 != 0) {
      array[i] = [];
      for (var j = 0; j < maxValue; j++) {
        var n = ((j + 1) * (i + 1)) / 2;
        if (j + 1 == maxValue) {
          array[i].push("| " + n.toString() + " ".repeat((maxNum).toString().length - n.toString().length + 1) + "|\n");
        } else {
          array[i].push("| " + n.toString() + " ".repeat((maxNum).toString().length - n.toString().length + 1));
        }
      };
    } else {
      array[i] = [pad];
    }
  }
  return array.join(" ");
};

console.log(multiplicationTable(5));
console.log(multiplicationTable(10));

＆＃13;

Answer 1

问题是你要连接数组而不是字符串。尝试将其转换为字符串并连接而不是附加到数组。

var multiplicationTable = function(maxValue) {
  var array = [];
  var maxNum = maxValue**2;
  y = 1;
  var pad = ("+--" + "-".repeat(maxNum.toString().length - y.toString().length + 1)).repeat(maxValue) + "\+\n";
  for (var i = 0; i <= maxValue * 2; i++) {
    if (i%2 != 0) {
      array[i] = "";
      for (var j = 0; j < maxValue; j++) {
        var n = ((j + 1) * (i + 1)) / 2;
        if (j + 1 == maxValue) {
          array[i] += "| " + n.toString() + " ".repeat((maxNum).toString().length - n.toString().length + 1) + "|\n";
        } else {
          array[i] += "| " + n.toString() + " ".repeat((maxNum).toString().length - n.toString().length + 1);
        }
      };
    } else {
      array[i] = [pad];
    }
  }
  return array.join(" ");
};

console.log(multiplicationTable(5));
console.log(multiplicationTable(10));

可生产

 +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
 | 1   | 2   | 3   | 4   | 5   | 6   | 7   | 8   | 9   | 10  |
 +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
 | 2   | 4   | 6   | 8   | 10  | 12  | 14  | 16  | 18  | 20  |
 +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
 | 3   | 6   | 9   | 12  | 15  | 18  | 21  | 24  | 27  | 30  |
 +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
 | 4   | 8   | 12  | 16  | 20  | 24  | 28  | 32  | 36  | 40  |
 +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
 | 5   | 10  | 15  | 20  | 25  | 30  | 35  | 40  | 45  | 50  |
 +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
 | 6   | 12  | 18  | 24  | 30  | 36  | 42  | 48  | 54  | 60  |
 +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
 | 7   | 14  | 21  | 28  | 35  | 42  | 49  | 56  | 63  | 70  |
 +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
 | 8   | 16  | 24  | 32  | 40  | 48  | 56  | 64  | 72  | 80  |
 +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
 | 9   | 18  | 27  | 36  | 45  | 54  | 63  | 72  | 81  | 90  |
 +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+
 | 10  | 20  | 30  | 40  | 50  | 60  | 70  | 80  | 90  | 100 |
 +-----+-----+-----+-----+-----+-----+-----+-----+-----+-----+

Answer 2

我会“加入”内部数组，然后是外部数据。如果您不想更改大部分代码。

我刚刚更改了您的返回语句的功能：

 return array.map(i => i.join("")).join("");

地图功能遍历所有元素，“转换” 数组 -Array为字符串 - 数组，通过内联函数，在每个项目上调用 join 函数最后，字符串 -Array将与最终的 join 函数一起加入。

<强>更新
没有Space的 join 可以防止输出失真。

var multiplicationTable = function(maxValue) {
  var array = [];
  var maxNum = maxValue**2;
  y = 1;
  var pad = ("+--" + "-".repeat(maxNum.toString().length - y.toString().length + 1)).repeat(maxValue) + "\+\n";
  for (var i = 0; i <= maxValue * 2; i++) {
    if (i%2 != 0) {
      array[i] = [];
      for (var j = 0; j < maxValue; j++) {
        var n = ((j + 1) * (i + 1)) / 2;
        if (j + 1 == maxValue) {
          array[i].push("| " + n.toString() + " ".repeat((maxNum).toString().length - n.toString().length + 1) + "|\n");
        } else {
          array[i].push("| " + n.toString() + " ".repeat((maxNum).toString().length - n.toString().length + 1));
        }
      };
    } else {
      array[i] = [pad];
    }
  }
  return array.map(i => i.join("")).join("");
  
};

console.log(multiplicationTable(5));
console.log(multiplicationTable(10));

Answer 3

您可以使用.replace(/,/g, '');

将逗号替换为空字符串

做这样的事情：

var multiplicationTable = function(maxValue) {
  var array = [];
  var maxNum = maxValue**2;
  y = 1;
  var pad = ("+--" + "-".repeat(maxNum.toString().length - y.toString().length + 1)).repeat(maxValue) + "\+\n";
  for (var i = 0; i <= maxValue * 2; i++) {
    if (i%2 != 0) {
      array[i] = [];
      for (var j = 0; j < maxValue; j++) {
        var n = ((j + 1) * (i + 1)) / 2;
        if (j + 1 == maxValue) {
          array[i].push("| " + n.toString() + " ".repeat((maxNum).toString().length - n.toString().length + 1) + "|\n");
        } else {
          array[i].push("| " + n.toString() + " ".repeat((maxNum).toString().length - n.toString().length + 1));
        }
      };
    } else {
      array[i] = [pad];
    }
  }

  var myTable = array.join(" ");
  return myTable.replace(/,/g, '');
};

console.log(multiplicationTable(5));
console.log(multiplicationTable(10));

Answer 4

工作小提琴https://jsfiddle.net/2097451n/6/

var multiplicationTable = function(maxValue) {
  var array = [];
  var maxNum = maxValue*2;
  y = 1;
  var pad = ("+--" + "-".repeat(maxNum.toString().length - y.toString().length + 1)).repeat(maxValue) + "\+\n";
  for (var i = 0; i <= maxValue * 2; i++) {
    if (i%2 != 0) {
      array[i] = [];
      for (var j = 0; j < maxValue; j++) {
        var n = ((j + 1) * (i + 1)) / 2;
        if (j + 1 == maxValue) {
          array[i].push("| " + n.toString() + " ".repeat((maxNum).toString().length - n.toString().length + 1) + "|\n");
        } else {
          array[i].push("| " + n.toString() + " ".repeat((maxNum).toString().length - n.toString().length + 1));
        }
      };

      // join nested array explicitly.
      //
      array[i] = array[i].join('')
    } else {
      array[i] = [pad];
    }
  }  
  return array.join("");
};

console.log(multiplicationTable(5));
console.log(multiplicationTable(10));

如何在没有逗号的情况下在JS中连接数组

4 个答案: