For-if 嵌套在 for-if 中

Question

//array

let posts = [{
    text: "First post!",
    id: "p1",
    comments: [{
        id: "c1",
        text: "First comment on first post!"
      },
      {
        id: "c2",
        text: "Second comment on first post!!"
      },
      {
        id: "c3",
        text: "Third comment on first post!!!"
      }
    ]
  },
  {
    text: "Aw man, I wanted to be first",
    id: "p2",
    comments: [{
        id: "c4",
        text: "Don't wory second poster, you'll be first one day."
      },
      {
        id: "c5",
        text: "Yeah, believe in yourself!"
      },
      {
        id: "c6",
        text: "Haha second place what a joke."
      }
    ]
  }
]


//loops
const removeComment = function(postId, commentID) {

  for (let post in posts) {
    if (posts[post].id == postId) {

      for (let Comment of posts.comments) {

        if (posts.comments[comment].id == commentID) {

          comment.splice(comment, 1)
        }
      }

    }
  }


}

//invoking the function

tweeter.removeComment("p2", "c6")

我正在尝试在特定 post（即“p2”）中获取评论（即“c6”），并将其从数组中删除。

为了遍历 Comments 对象，我写了一个 for if 嵌套在 for-if 中；我没有收到任何错误，但第一个 for-if 运行正常。谢谢

Answer 1

您的函数中有几处需要更改。您正在使用 let post in posts 循环给出数字，因此当您尝试将其作为对象访问时您的逻辑已关闭。

let Comment of posts.comments

您可能希望使用匹配的 postId 遍历特定评论。

您正在使用未定义的 comment。检查下面的代码片段，运行并根据需要进行编辑。

let posts = [{
    text: "First post!",
    id: "p1",
    comments: [{
        id: "c1",
        text: "First comment on first post!"
      },
      {
        id: "c2",
        text: "Second comment on first post!!"
      },
      {
        id: "c3",
        text: "Third comment on first post!!!"
      }
    ]
  },
  {
    text: "Aw man, I wanted to be first",
    id: "p2",
    comments: [{
        id: "c4",
        text: "Don't wory second poster, you'll be first one day."
      },
      {
        id: "c5",
        text: "Yeah, believe in yourself!"
      },
      {
        id: "c6",
        text: "Haha second place what a joke."
      }
    ]
  }
]


//loops
const removeComment = (postId, commentID)=> {
  for (let post of posts) {
    if (post['id'] == postId) {
      for (let Comment of post.comments) {
        if (Comment['id'] == commentID) {
          post.comments.splice(post.comments.indexOf(Comment),1);
        }
      }
    }
  }
}
removeComment("p2","c6");
console.log(posts);

For-if 嵌套在 for-if 中

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