javascript - 使用 lodash 或 underscorejs 查找字段的数组计数

Question

我需要获取数组中每种帐户类型的计数。我尝试了循环数组并为每个数组增加一个计数器的正常方法帐户类型。你能帮我在 lodash 或 underscore js 中做同样的事情吗？

非常感谢您的帮助。谢谢。

input_array = [
    {
        account_id: '4304bf0381140b8fcccbdddea3571a53facebook',
        account_type: 'facebook'
    },
    {
        account_id: '4304bf0381140b8fcccbdddea332434facebook',
        account_type: 'facebook'
    },
    {
        account_id: '5824fb40c4a97e21ef9715ea69c1cfb9twitter',
        account_type: 'twitter'
    },
    {
        account_id: '5824fb40c4a97e21ef9715ea432423twitter',
        account_type: 'twitter'
    },
    {
        account_id: '2c13790be20a06a35da629c71e548afexing',
        account_type: 'xing'
    },
    {
        account_id: 'd1376b07b144130c4f041e223dfb1197weibo',
        account_type: 'weibo'
    },
    {
        account_id: 'd1376b07b144130c4f041e223df4343weibo',
        account_type: 'weibo'
    }
]
output_array = [
    {
        type: "facebook",
        count: 2
    },
    {
        type: "twitter",
        count: 2
    },
    {
        type: "xing",
        count: 1
    },
    {
        type: "weibo",
        count: 2
    }
]

已尝试

input_array.forEach(function(data){
    if(data.account_type=='facebook'){
        count++;//forfacebook
    }
});

Answer 1

您可以使用countBy...

_.countBy(input_array, function(obj) {
    return obj.account_type;
});