Public Class Form1
Private Sub btnAddCat_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnAddCat.Click
If txtAdd.Text <> "" Then
comboBox1.Items.Add(txtAdd.Text)
txtAdd.Clear()
Else
MessageBox.Show("Fill the blanket")
End If
End Sub
End Class
如果用户关闭应用程序应该看到项目但没有项目有人可以帮忙吗?谢谢