如何按项目类型对数组进行排序，其中字符串应首先出现，然后是浮点数和整数，同时保持相同的类型优先级并且不使用额外的数组

Question

输入：

[7,"a","b",5, 0.1, "c", 0.5, 9, 1, "e", "m", 0.3, 8.5, 74, 89,"f","r",0.5 ,"x", "y", 4, 7]

输出：

["a", "b", "c", "e", "m", "f", "r", "x", "y", 0.1, 0.5, 0.3, 8.5, 0.5, 7, 5, 9, 1, 74, 89, 4, 7]


function sorter(arr) {
    var arr1, arr2, arr3;
    arr1 = [];
    arr2 = [];
    arr3 = [];
    for (var i = 0; i < arr.length; i++) {
        if (typeof arr[i] === "string") {
            arr1.push(arr[i]);
        } else if (typeof arr[i] === 'number' && !isNaN(arr[i])) {
            if (Number.isInteger(arr[i])) {
                arr3.push(arr[i]);
            } else {
                arr2.push(arr[i]);
            }
        }
    }
    return [...arr1, ...arr2, ...arr3];
}

Answer 1

将 sort() 方法与比较类型而不是值的比较函数一起使用。

function sorter(arr) {
  function type_index(val) {
    const types = ["string", "float", "integer"];
    let type;
    if (typeof val == "string") {
      type = "string";
    } else if (typeof val == "number" && Number.isInteger(val)) {
      type = "integer";
    } else if (typeof val == "number" && !isNaN(val)) {
      type = "float";
    }
    return types.indexOf(type);
  }

  return arr.sort((a, b) => type_index(a) - type_index(b));
}

console.log(sorter([7,"a","b",5, 0.1, "c", 0.5, 9, 1, "e", "m", 0.3, 8.5, 74, 89,"f","r",0.5 ,"x", "y", 4, 7]));

Answer 2

基于单个 sort 比较器回调的方法 ...

function orderByItemTypeOnly(a, b) {
  const precedences = {
    'string': 1,
    'float': 2,
    'int': 3,
  };
  const getType = val =>
    ((typeof val === 'number') && Number.isFinite(val))
      ? Number.isInteger(val) && 'int' || 'float'
      : (typeof val);

  const aType = getType(a);
  const bType = getType(b);

  return (
    (precedences[aType] || 4) - (precedences[bType] || 4)
  );
}

console.log([

  7, "a", "b", 5, 0.1, "c", 0.5, 9, 1, "e", "m",
  0.3, 8.5, 74, 89, "f", "r", 0.5, "x", "y", 4, 7

].sort(orderByItemTypeOnly));

.as-console-wrapper { min-height: 100%!important; top: 0; }

也有可能不是通过 sort 而是基于 reduce 方法来解决这个任务...

function collectAndShiftItemByType(list, item, idx, arr) {
  if (list.length === 0) {
    list.push([], [], [], []);
  }
  const typeListIndex = ((typeof item === 'number') && Number.isFinite(item))
    ? (Number.isInteger(item) && 2 || 1)
    : (typeof item === 'string') ? 0 : 3;

  // push into sub lists ... [0]string, [1]float, [2]integer, [3]unknown.
  list[typeListIndex].push(item);

  if (idx >= arr.length - 1) {
    list = list[0]
      .concat(list[1])
      .concat(list[2])
      .concat(list[3]);
  }
  return list;
}

console.log([

  7, "a", "b", 5, 0.1, "c", 0.5, 9, 1, "e", "m",
  0.3, 8.5, 74, 89, "f", "r", 0.5, "x", "y", 4, 7

].reduce(collectAndShiftItemByType, []));

.as-console-wrapper { min-height: 100%!important; top: 0; }

如何按项目类型对数组进行排序，其中字符串应首先出现，然后是浮点数和整数，同时保持相同的类型优先级并且不使用额外的数组

How to sort an array by item type where strings should appear 1st then floats and integers while keeping same type precedence and no extra arrays used

javascript

arrays

performance

sorting

comparison