使用jQuery,我如何遍历一个对象,并获得一个密钥的唯一值与每个值的计数?JavaScript:从一组对象中获取唯一值和它们的计数?
例如,对于此阵:
var electrons = [
{ name: 'Electron1', distance: 1 },
{ name: 'Electron2', distance: 1 },
{ name: 'Electron3', distance: 2 },
{ name: 'Electron4', distance: 2 },
{ name: 'Electron5', distance: 2 },
{ name: 'Electron6', distance: 2 },
{ name: 'Electron7', distance: 2 },
{ name: 'Electron8', distance: 2 },
{ name: 'Electron9', distance: 2 },
{ name: 'Electron10', distance: 2 },
{ name: 'Electron11', distance: 3 },
];
我希望得到以下:
var distance_counts = {1: 2, 2: 8, 3: 1};
我这有,这工作,但有点笨拙:
var radius_counts = {};
for (var i = 0; i < electrons.length; i++) {
if (electrons[i].distance in radius_counts) {
radius_counts[electrons[i].distance] += 1;
} else {
radius_counts[electrons[i].distance] = 1;
}
}
试试这个http://stackoverflow.com/questions/1960473/unique-values-in-an-array –
@Artem - 这是一个完全关于获取一组唯一值的不同问题。 – Richard
初始数组是否总是按原样排序? – sp00m