How to Locate TreeView Node By Text

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Many times while developing Delphi applications using the TreeView component I've bumped into a situation to need to search for a tree node given by only the text of the node.

In this article I'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 do
begin
if UpperCase(Node.Text) = UpperCase(AValue) then
begin
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!')
else
begin
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! What if you want to search for a node at the same level as the calling node - where this calling node is also provided to the function!