主题：一键还原窗口内的所有组合框控件为初始状态

你弄个开发版的格式，试用版用户插不上嘴了。

哪个表都可以隐藏。

For Each c As WinForm.Control In e.Form.Controls
    If TypeOf c Is WinForm.ComboBox Then
        Dim cmb As WinForm.ComboBox = c
        cmb.Text = ""
    ElseIf TypeOf c Is WinForm.TextBox Then
        Dim txt As WinForm.TextBox = c
        txt.Text = ""
    ElseIf TypeOf c Is WinForm.CheckedComboBox Then
        Dim chcmb As WinForm.CheckedComboBox = c
        chcmb.Text = ""
    End If
Next