如何查找值是否在嵌套数组中[关闭]

Question

var array = [["1", "2], ["3", "4"], ["5", "6"]]

我想看看变量中是否有数字“4”

Answer 1

您可以使用Array.prototype.flat() 和Array.prototype.includes()：

const array = [["1", "2"], ["3", "4"], ["5", "6"]],

      result = array.flat().includes('4')
      
console.log(result)      

上面很容易调整（通过将flattening深度作为参数传递给flat()）到几乎任何嵌套深度。

如果这只是 2 个级别的深度，您可能会选择Array.prototype.some() 和 Array.prototype.includes() 的性能更高的组合：

const array = [["1", "2"], ["3", "4"], ["5", "6"]],

      result = array.some(a => a.includes('4'))
      
console.log(result)

Answer 2

const array = [["1", "2"], ["3", "4"], ["5", "6"]];
const value = '4';
/*
 * const result = (new RegExp(value,'gi')).test(array.join()) 
 * result will be true for `4` , `44` , `444` ...
 */

/*
 * to get the exact match we have to use word boundary
 */
const result = (new RegExp(`\\b${value}\\b`,'g')).test(array.join())

Word boundary: \b

Answer 3

function CheckNumberInArray(array, number) {
    FoundNumber = False;
    for (var i = 0; i < array.length; i++) {
        for (var j=0; j < array[i].length;j++) {
          if (array[i][j] == number) {
              FoundNumber = true;   // Found it
          }
        }
    }
    return FoundNumber;   // Not found
}