Question

我有一个数组：

main = [{
           data: x,
           numberField:  1;
 }, {      data: y,
           numberField:  2;
 }, {      data: x,
           numberField:  3;
 },
  {        data:z
           numberField:  4;
 },
    {      data: q
           numberField:  5;
 }]
fixedElements = [ 3, 5]

我需要：

 fixedElements .includes(a.numberField) - fixedElements .includes(b.numberField)

因为我需要检查两个即将到来的值是否在数组a中而不是对它们进行排序，而是对其余值进行排序。当我尝试这样做时，打字错误

  left/right hand-side of the argument needs to be of type any or number.

我的初始排序功能为：

  sort(a,b) {
  if(a.numberField > b.numberField)
       return -1

  if(a.numberField < b.numberField)
     return 1;

    }

所以我想检查即将到来的a或b是否在fixedElements数组中，并将它们保留到最后。还有其他办法吗？

Answer 1

您可以使用+符号（typescript playground demo）将布尔值转换为数字：

+fixedElements.includes(a.numberField) - +fixedElements.includes(b.numberField)`

这是排序逻辑（typescript playgroud - 检查控制台）：

＆＃13;

const main = [{"data":"x","numberField":1},{"data":"y","numberField":2},{"data":"x","numberField":3},{"data":"z","numberField":4},{"data":"q","numberField":5}]

// I'm using a Set instead of an array, because Set.has is faster than Array.includes
const fixedElements = new Set([3, 5])

main.sort((a, b) => {
  const aF = fixedElements.has(a.numberField)
  const bF = fixedElements.has(b.numberField)
  
  if(!aF && !bF) return b.numberField - a.numberField
  
  return +aF - +bF
})

console.log(main)

＆＃13;

Answer 2

您可以使用自定义排序功能并检查numberField数组中是否存在fixedElements值并保持未排序，否则根据numberField值对其进行排序。

＆＃13;

let main = [{ data: 'x', numberField: 1}, { data: 'y', numberField: 2}, { data: 'x', numberField: 3}, { data:'z', numberField: 4}, { data: 'q', numberField: 5}], 
      fixedElements = [3, 5];
main.sort((a,b) => {
  if([a,b].some(({numberField}) => fixedElements.includes(numberField)))
   return +fixedElements.includes(a.numberField) - +fixedElements.includes(b.numberField);
  else
    return +b.numberField - +a.numberField
});
console.log(main);

＆＃13;

Answer 3

您可以使用includes()方法中的sort方法进行检查。

var array = [{
    data: 'x',
    numberField: 1
  }, {
    data: 'y',
    numberField: 2
  }, {
    data: 'x',
    numberField: 3
  }, {
    data: 'z',
    numberField: 4
  }, {
    data: 'q',
    numberField: 5
  }],
  fixedElements = [3, 5];

array.sort((a, b) => {
  a = +a.numberField;
  b = +b.numberField;
  return (fixedElements.includes(a) - fixedElements.includes(b) || b - a);
});

console.log(array)

Typescript减去两个布尔值

3 个答案: