Hi dnnyobi,
Check this example. Now please take its reference and correct your code.
C#
protected void OnRearrange(object sender, EventArgs e)
{
string[] animals = txtAnimals.Text.Split(' ').ToList().OrderBy(x => x.Trim()).ToArray();
txtAnimals.Text = string.Join(" ", animals);
}
VB.Net
Private Sub OnRearrange(sender As Object, e As EventArgs) Handles btnRearrange.Click
Dim animals As String() = txtAnimals.Text.Split(" ").ToList().OrderBy(Function(x) x.Trim()).ToArray()
txtAnimals.Text = String.Join(" ", animals)
End Sub
Screenshot