How to Locate TreeView Node By Text

While developing Delphi applications using the TreeView component, you may bump into a situation where you need to search for a tree node given by only the text of the node.

In this article we'll present you with one quick and easy function to get TreeView node by text.

A Delphi Example

First, we'll build a simple Delphi form containing a TreeView, a Button, CheckBox and an Edit component—leave all the default component names.

As you might imagine, the code will work something like: if GetNodeByText given by Edit1.Text returns a node and MakeVisible (CheckBox1) is true then select node.

The most important part is the GetNodeByText function.

This function simply iterates through all the nodes inside the ATree TreeView starting from the first node (ATree.Items[0]). The iteration uses the GetNext method of the TTreeView class to look for the next node in the ATree (looks inside all nodes of all child nodes). If the Node with text (label) given by AValue is found (case insensitive) the function returns the node. The boolean variable AVisible is used to make the node visible (if hidden).

function GetNodeByText
(ATree : TTreeView; AValue:String; 
 AVisible: Boolean): TTreeNode;
var
 Node: TTreeNode;
begin
 Result := nil;
 if ATree.Items.Count = 0 then Exit;
 Node := ATree.Items[0];
 while Node nil dobeginif UpperCase(Node.Text) = UpperCase(AValue) thenbegin
 Result := Node;
 if AVisible then
 Result.MakeVisible;
 Break;
 end;
 Node := Node.GetNext;
 end;
end;

This is the code that runs the 'Find Node' button OnClick event:

procedure TForm1.Button1Click(Sender: TObject);
var
 tn : TTreeNode;
begin
 tn:=GetNodeByText(TreeView1,Edit1.Text,CheckBox1.Checked);
 if tn = nil then
 ShowMessage('Not found!')
 elsebegin
 TreeView1.SetFocus;
 tn.Selected := True;
 end;
end;

Note: If the node is located the code selects the node, if not a message is displayed.

That's it. As simple as only Delphi can be. However, if you look twice, you'll see something is missing: the code will find the FIRST node given by AText.