Question

I am attempting to change to a tab dependent on a treeView node selection:

e.g.

private void hostView_AfterSelect(object sender, TreeViewEventArgs e)
{
    string selectedNodeText = e.Node.Text;
    // MessageBox.Show(selectedNodeText);
    tabControl1.SelectTab(selectedNodeText);
}

Although when the method runs it returns the following:

tabControl1.SelectTab(selectedNodeText); >> Value cannot be null.

selectedNodeText is definitely a value / not null, as I tested it using MessageBox.Show

Answer 1

Assuming the text of your selected node is not null, you’ll have to set the Name properties of your TabPages if you use the SelectTab method that takes a string as input.

Set Name properties of your TabPages with same values as Text properties of your nodes.

EDIT:
MSDN is a great resource for developers. In your particular case, when receiving an ArgumentNullException, you should have tried to read the documentation of the SelectTab method.