Javascript - 從外部數組中刪除對我的對象的引用

Question

我有一個解引用JavaScript對象並將其設置爲NULL的問題。

在這裏，我有一個文件夾實現，支持遞歸子目錄刪除。請參閱我的評論以瞭解我的困境。

function Folder(name, DOM_rows) { 
    this.name = name; 
    this.files = [].concat(DOM_rows); 
    this.subdirs = []; 
} 

Folder.prototype.AddDir(name, DOM_rows) { 
    this.subdirs.push(new Folder(name, DOM_rows)); 
} 

Folder.prototype.RemoveDir(folder) { 
    var stack = [folder]; 
    while(stack.length > 0) { 
     var cur = stack.pop(); 
     // do a post-order depth-first traversal, so dig to the deepest subdir: 
     if(cur.subdirs.length > 0) { 
      while(cur.subdirs.length > 0) { stack.push(cur.subdirs.pop()); } 
     } else { 
      // arrived at a leaf-level: 
      cur.files = null; 
      // now how do I delete cur from it's parent's subdirs array? 
      // the only way I know how is to keep a "cur.parentDir" reference, 
      // then find parent.subdirs[ index of cur ] and slice it out. 
      // How can I do the JS-equivalent of *cur = NULL? 
     } 
    } 
} 

Answer 1

注意你，你懷疑沒有大問題，因爲所有子目錄，但在folder您RemoveDir將由stack.push(cur.subdirs.pop());線

從他們的父母的subdir刪除，以找到一個子目錄家長，你可以利用的對象，如詞典，而不是subdirs的數組：給定一個文件夾

function Folder(name, DOM_rows, parent) { 
    this.name = name; 
    this.parent = parent; 
    this.files = [].concat(DOM_rows); 
    this.subdirs = {}; 
    this.subdirCount = 0; 
} 

Folder.prototype.AddDir = function (name, DOM_rows) { 
    if (this.subdirs[name]) { 
     return null; 
    } 
    ++this.subdirCount; 
    return this.subdirs[name] = new Folder(name, DOM_rows, this); 
} 

，你可以從父刪除文件夾：

delete folder.parent.subdirs[folder.name]; 

這裏的預購版本：

Folder.prototype.RemoveDir = function (folder) { 
    if (this.subdirs[folder.name] === folder) { 
     var stack = [folder]; 
     while(stack.length > 0) { 
      var cur = stack.pop(); 
      // pre-order 
      delete cur.files; 
      // if there's other processing to be done, now's the time to do it 
      for (subdir in cur.subdirs) { 
       stack.push(cur.subdirs[subdir]); 
       delete cur.subdirs[subdir]; 
      } 
      // it's unnecessary to set subdir count, since 'cur' has been deleted 
      //cur.subdirCount = 0; 
     } 
     delete this.subdirs[folder.name]; 
     --this.subdirCount; 
    } 
} 

和遞歸後序版本：

Folder.prototype.RemoveChildren = function() { 
    for (subdir in this.subdirs) { 
     this.RemoveDir(this.subdirs[subdir]); 
    } 
} 

Folder.prototype.RemoveDir = function (folder) { 
    if (this.subdirs[folder.name] === folder) { 
     folder.RemoveChildren(); 
     folder.files = []; 
     delete this.subdirs[folder.name]; 
     --this.subdirCount; 
    } 
} 

而且迭代後序版本：

Array.prototype.top = function() { return this[this.length-1]; } 

Folder.prototype.RemoveDir = function (folder) { 
    if (this.subdirs[folder.name] === folder) { 
     var stack = [folder]; 
     while(stack.length > 0) { 
      var cur = stack.top(); 
      if (cur.subdirCount > 0) { 
       for (subdir in cur.subdirs) { 
        stack.push(cur.subdirs[subdir]); 
        delete cur.subdirs[subdir]; 
       } 
       cur.subdirCount = 0; 
      } else { 
       stack.pop(); 
       delete cur.files; 
       // other post-order processing 
      } 
     } 
     delete this.subdirs[folder.name]; 
    } 
} 

雖然，除非在處理時你需要採取額外的步驟g刪除文件&文件夾，簡單：

Folder.prototype.RemoveDir = function (folder) { 
    if (this.subdirs[folder.name] === folder) { 
    delete this.subdirs[folder.name]; 
    } 
} 

應該就足夠了。

Answer 2

一切都是javascript傳遞的值，所以「* cur = NULL」是不可能的。基本上，你這裏有下列選項如你所說

如果你的文件夾層次結構有一個衆所周知的根，從根瀏覽尋父對象

使用像DOM removeChild之

• 使用的parentID（它在parent上被調用），而不是removeNode（它在節點本身被調用）。

Answer 3

我今天想要做同樣的事情。 我已經通過將對象的索引存儲爲對象本身的屬性來解決它。

當你添加：

myObj.ID = myArr.push(myObj); 

所以要去除它，你

myArr[myObj.ID] = null; 

我猜你解決它現在，但你可以做幾乎是相同的;這比使用對象更簡單。