Delphi World - Копировать нижние узлы TTreeView во второй TTreeView
Delphi World - это проект, являющийся сборником статей и малодокументированных возможностей  по программированию в среде Delphi. Здесь вы найдёте работы по следующим категориям: delphi, delfi, borland, bds, дельфи, делфи, дэльфи, дэлфи, programming, example, программирование, исходные коды, code, исходники, source, sources, сорцы, сорсы, soft, programs, программы, and, how, delphiworld, базы данных, графика, игры, интернет, сети, компоненты, классы, мультимедиа, ос, железо, программа, интерфейс, рабочий стол, синтаксис, технологии, файловая система...
Копировать нижние узлы TTreeView во второй TTreeView

Оформил: DeeCo
Автор: http://www.swissdelphicenter.ch

type
   {: Callback to use to copy the data of a treenode when the 
     node itself is copied by CopySubtree. 
   @param oldnode is the old node 
   @param newnode is the new node 
   @Desc Use a callback of this type to implement your own algorithm 
     for a node copy. The default just uses the Assign method, which 
     produces a shallow copy of the nodes Data property. }
   TCopyDataProc = procedure(oldnode, newnode : TTreenode);

 {: The default operation is to do a shallow copy of the node, via 
Assign. }
 procedure DefaultCopyDataProc(oldnode, newnode : TTreenode);
 begin
   newnode.Assign(oldnode);
 end;

 {-- CopySubtree 
-------------------------------------------------------}
 {: Copies the source node with all child nodes to the target treeview. 
@Param sourcenode is the node to copy 
@Param target is the treeview to insert the copied nodes into 
@Param targetnode is the node to insert the copy under, can be nil to 
  make the copy a top-level node. 
@Param CopyProc is the (optional) callback to use to copy a node. 
  If Nil is passed for this parameter theDefaultCopyDataProc will be 
used. 
@Precondition  sourcenode <> nil, target <> nil, targetnode is either 
  nil or a node of target 
@Raises Exception if targetnode happens to be in the subtree rooted in 
  sourcenode. Handling that special case is rather complicated, so we 
  simply refuse to do it at the moment. 
}{ Created 2003-04-09 by P. Below ----------------------------------------------------------------------- 
}
 procedure CopySubtree(sourcenode : TTreenode; target : TTreeview;
   targetnode : TTreenode; CopyProc : TCopyDataProc = nil);
 var
   anchor : TTreenode;
   child : TTreenode;
 begin { CopySubtree }
   Assert(Assigned(sourcenode),
     'CopySubtree:sourcenode cannot be nil');
   Assert(Assigned(target),
     'CopySubtree: target treeview cannot be nil');
   Assert((targetnode = nil) or (targetnode.TreeView = target),
     'CopySubtree: targetnode has to be a node in the target treeview.');

   if (sourcenode.TreeView = target) and
     (targetnode.HasAsParent(sourcenode) or (sourcenode =
     targetnode)) then
     raise Exception.Create('CopySubtree cannot copy a subtree to one of the ' +
       'subtrees nodes.');

   if not Assigned(CopyProc) then
     CopyProc := DefaultCopyDataProc;

   anchor := target.Items.AddChild(targetnode, sourcenode.Text);
   CopyProc(sourcenode, anchor);
   child := sourcenode.GetFirstChild;
   while Assigned(child) do
    begin
     CopySubtree(child, target, anchor, CopyProc);
     child := child.getNextSibling;
   end; { While }
 end; { CopySubtree }


 procedure TForm1.Button1Click(Sender : TObject);
 begin
   if assigned(treeview1.selected) then
     CopySubtree(treeview1.selected, treeview2, nil);
 end;
Проект Delphi World © Выпуск 2002 - 2017
Автор проекта: Эксклюзивные курсы программирования