Question

Private Sub RichTextView_TextChanged(ByVal sender As Object, ByVal e As 
   KeyPressEventArgs) Handles RichTextView.KeyPress, RichTextView.TextChanged

    Dim c As Char = e.KeyChar
    Dim i As Integer = Asc(c)
    Dim h As Char = Chr(i)

capitalise_first_letter.Add(h)
End Sub

The above code produces the error: Unable to cast object of type 'System.EventArgs' to type 'System.Windows.Forms.KeyPressEventArgs'. It throws the error at capitalise_first_letter.Add(h) (capitalise_first_letter is a List of String).

Why? Since h is e.KeyChar put through transformations?

Answer 1

This is because you’re also trying to use the same routine to handle RichTextView.TextChanged, which does not pass KeyPressEventArg.

You need a separate event handler for the TextChanged event if you want to allow this to be KeyPressEventArgs.