I have a task, my textbox accepts only first character capital lettr and remaing characters normal.
Use KeyPress event of textbox:
private void txt_KeyPress(object sender, KeyPressEventArgs e) { if (txt.Text != "" && !Char.IsUpper(txt.Text, 0)) { txt.Text = Char.ToUpper(txt.Text[0]) + txt.Text.Substring(1); } }