Traversing an Entire Tree View’s Hierarchy

In a tree control it often becomes necessary to display the complete path in the tree from the
selected item to the root. The path can be displayed as a string comprising of the labels of the tree items and
starting from the root node to the selected item or from the selected item to the root item.
The following function traverses the tree and retrieves the path
from the selected item to the root.


// GetTreeHeirarchy – Retrieves the tree heirarchy as a string comprising of item
labels from root node to selected node
// hTItem – The HTREEITEM of selected item
// cstrTreeHierarchy – String to store the Tree heirarchy
// bTopToBottom – TRUE if the path should be from root to selected item
FALSE if the path should be from the selected item to the root


void CMyTreeCtrl::GetTreeHierarchy(HTREEITEM hTItem, CString &cstrTreeHierarchy, const BOOL bTopToBottom)
{
HTREEITEM hTRootItem = GetParentItem(hTItem);
if ( hTRootItem == NULL ){
cstrTreeHierarchy += (GetItemText(hTItem)+”\”);
return;
}
if (!bTopToBottom)
cstrTreeHierarchy += (GetItemText(hTItem)+”\”);
GetTreeHierarchy(hTRootItem, cstrTreeHierarchy);
if (bTopToBottom)
cstrTreeHierarchy += (GetItemText(hTItem)+”\”);
}

To get the tree heirarchy, this function can be called as follows:


   CString csTreeHeirarchy;
   m_pcMyTreeCtrl->GetTreeHierarchy(m_pcMyTreeCtrl->GetSelectedItem(), csTreeHeirarchy, TRUE);
		

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