如何在 javascript 中检索数组中相同值的数量

How Can I retrieve the number of identical values in an array in javascript?

本文关键字:数组 javascript 检索      更新时间:2023-09-26

var array = ['box','box','line','time','box']

例如:框重复几次

你来了:

    var array = ['box','box','line','time','box'],
    map = {},
    key;
array.forEach(function(item) {
    if (map[item] === undefined) {
        map[item] = 1;
    } else {
        map[item]++;
    }
});
for (key in map) {
    console.log(" key:", key, " repeated:", map[key]);
}