在PHP中,您可以。。。

range(1, 3); // Array(1, 2, 3)
range("A", "C"); // Array("A", "B", "C")

也就是说,有一个函数可以通过传递上下限来获得一系列数字或字符。

JavaScript本机是否有内置的功能?如果没有,我将如何实施?


当前回答

对于具有良好向后兼容性的更像红宝石的方法:

范围([开始],结束=0),其中开始和结束是数字

var range = function(begin, end) {
  if (typeof end === "undefined") {
    end = begin; begin = 0;
  }
  var result = [], modifier = end > begin ? 1 : -1;
  for ( var i = 0; i <= Math.abs(end - begin); i++ ) {
    result.push(begin + i * modifier);
  }
  return result;
}

示例:

range(3); //=> [0, 1, 2, 3]
range(-2); //=> [0, -1, -2]
range(1, 2) //=> [1, 2]
range(1, -2); //=> [1, 0, -1, -2]

其他回答

在边界内生成整数数组的递归解决方案。

function intSequence(start, end, n = start, arr = []) {
  return (n === end) ? arr.concat(n)
    : intSequence(start, end, start < end ? n + 1 : n - 1, arr.concat(n));
}

$> intSequence(1, 1)
<- Array [ 1 ]

$> intSequence(1, 3)
<- Array(3) [ 1, 2, 3 ]

$> intSequence(3, -3)
<- Array(7) [ 3, 2, 1, 0, -1, -2, -3 ]

如果我们输入类似[4,2]的内容,我们将得到[2,3,4]作为输出,我们可以使用它。

function createRange(array) {
  var range = [];
  var highest = array.reduce(function(a, b) {
    return Math.max(a, b);
  });
  var lowest = array.reduce(function(a, b) {
    return Math.min(a, b);
  });
  for (var i = lowest; i <= highest; i++) {
    range.push(i);
  }
  return range;
}

您可以使用lodash函数.range(10)https://lodash.com/docs#range

您可以使用以下一行代码使事情简短明了

var启动=4;var端=20;console.log(数组(end-start+1).fill(start).map((x,y)=>x+y));

要紧密复制的类型脚本函数

/**
 * Create a generator from 0 to stop, useful for iteration. Similar to range in Python.
 * See: https://stackoverflow.com/questions/3895478/does-javascript-have-a-method-like-range-to-generate-a-range-within-the-supp
 * See: https://docs.python.org/3/library/stdtypes.html#ranges
 * @param {number | BigNumber} stop
 * @returns {Iterable<number>}
 */
export function range(stop: number | BigNumber): Iterable<number>
/**
 * Create a generator from start to stop, useful for iteration. Similar to range in Python.
 * See: https://stackoverflow.com/questions/3895478/does-javascript-have-a-method-like-range-to-generate-a-range-within-the-supp
 * See: https://docs.python.org/3/library/stdtypes.html#ranges
 * @param {number | BigNumber} start
 * @param {number | BigNumber} stop
 * @returns {Iterable<number>}
 */
export function range(
  start: number | BigNumber,
  stop: number | BigNumber,
): Iterable<number>

/**
 * Create a generator from start to stop while skipping every step, useful for iteration. Similar to range in Python.
 * See: https://stackoverflow.com/questions/3895478/does-javascript-have-a-method-like-range-to-generate-a-range-within-the-supp
 * See: https://docs.python.org/3/library/stdtypes.html#ranges
 * @param {number | BigNumber} start
 * @param {number | BigNumber} stop
 * @param {number | BigNumber} step
 * @returns {Iterable<number>}
 */
export function range(
  start: number | BigNumber,
  stop: number | BigNumber,
  step: number | BigNumber,
): Iterable<number>
export function* range(a: unknown, b?: unknown, c?: unknown): Iterable<number> {
  const getNumber = (val: unknown): number =>
    typeof val === 'number' ? val : (val as BigNumber).toNumber()
  const getStart = () => (b === undefined ? 0 : getNumber(a))
  const getStop = () => (b === undefined ? getNumber(a) : getNumber(b))
  const getStep = () => (c === undefined ? 1 : getNumber(c))

  for (let i = getStart(); i < getStop(); i += getStep()) {
    yield i
  }
}