javascript - array.filter 不返回 Reactjs 中父数组的嵌套数组

Question

我有一个嵌套数组。我使用 array.filter 从父数组中获取子数组。

我的数据是这样的:

"accounts": [
    {

        "ID": "001yQdmAAE",
        "email": "<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="4c25222423212962393f293e0c2d38233e622f2321" rel="noreferrer noopener nofollow">[email protected]</a>",
        "users": [
            {
                "Name": "Inhome User",                    
                "MobilePhone": "34877"
            }
        ]
    },
    {
        "ID": "00mAAE",
        "email": "<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="167f78386365736456776279643875797b" rel="noreferrer noopener nofollow">[email protected]</a>",
        "users": [
            {
                "Name": "Inhome r",                    
                "MobilePhone": "300077"
            }
        ]
   }]

我想根据 ID 从帐户数组中获取用户数组。我尝试了array.filter。它返回

    { "ID": "001yQdmAAE",
      "email": "<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="abc2c5c3c4c6ce85ded8ced9ebcadfc4d985c8c4c6" rel="noreferrer noopener nofollow">[email protected]</a>",
      "users": [
        {
           "Name": "Inhome User",                    
           "MobilePhone": "34877"
        }
    }

我只想要用户数组

const res=this.state.data.filter((res)=>{
 if(res.ID==record.ID){
       return res.users;
 }
});
console.log(res);

Answer 1

这并不完全是filter作品。 filter 的回调函数应返回一个 bool 结果，该结果确定传入回调的元素是否应包含在 filter 的返回值中。执行过滤后，我们将 map每个结果对象提取其 users 属性。

const /*this.state.*/data = {"accounts": [{"ID": "001yQdmAAE","email": "<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="7b12151314161e550e081e093b1a0f140955181416" rel="noreferrer noopener nofollow">[email protected]</a>","users": [{"Name": "Inhome User","MobilePhone": "34877"}]},{"ID": "00mAAE","email": "<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="94fdfabae1e7f1e6d4f5e0fbe6baf7fbf9" rel="noreferrer noopener nofollow">[email protected]</a>","users": [{"Name": "Inhome r","MobilePhone": "300077"}]}]};

const targetID = "00mAAE";
const result = data.accounts
  .filter(e => e.ID === targetID)
  .map(e => e.users);

console.log(result);

但是如果 ID 是唯一的，则使用 find而不是 filter，后者仅定位第一个匹配项:

const data = {"accounts": [{"ID": "001yQdmAAE","email": "<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="ddb4b3b5b2b0b8f3a8aeb8af9dbca9b2aff3beb2b0" rel="noreferrer noopener nofollow">[email protected]</a>","users": [{"Name": "Inhome User","MobilePhone": "34877"}]},{"ID": "00mAAE","email": "<a href="https://stackoverflow.com/cdn-cgi/l/email-protection" class="__cf_email__" data-cfemail="1a7374346f697f685a7b6e756834797577" rel="noreferrer noopener nofollow">[email protected]</a>","users": [{"Name": "Inhome r","MobilePhone": "300077"}]}]};

const targetID = "00mAAE";
const result = data.accounts.find(e => e.ID === targetID);

if (result) {
  console.log(result.users);
}