[英]Access variables declared inside JavaScript switch statement from outside
[英]how to access variables declared in map outside it?
我有两个 map 函数并将其数据分配给变量,我想比较它们
!followerLoading && (
followersData.map((e) =>
{
const myFollowers = e.requested_profile.Userlink
}
)
)
!followingLoading && (
followingData.map((e) =>
{
const myFollowings = e.requesting_profile.Userlink
}
)
)
const btntext = myFollowers===myFollowings ? "Following" : "Follow"
映射 function 将在迭代时返回一个数组。 解决此问题的一种方法是比较两个 arrays
const myFollowers = !followerLoading && (
followersData.map((e) => e.requested_profile.Userlink )
)
const myFollowings = !followingLoading && (
followingData.map((e) => e.requesting_profile.Userlink)
)
const btntext = arr1.some(r=> arr2.includes(r)) ? "Following" : "Follow"
您不能访问其范围之外的变量。 因此,请执行以下操作:
在 scope of.map() 之外声明myFollowers
和myFollowings
并用一些值初始化它们。
然后,您可以从 .map() 方法为这些变量赋值。
let myFollowers = null;
let myFollowing = null;
followerLoading && (
followersData.map((e) =>
{
myFollowers = e.requested_profile.Userlink
}
)
)
// Same for the other one
const btntext = myFollowers===myFollowings ? "Following" : "Follow";
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