軟件試用期設置

1.第一次窗體顯示前發生：

1   public FrmMain()
2         {
3             InitializeComponent();
4             Load += FrmMain_Load;
5           }

2.主窗體Load事件

 1   private void FrmMain_Load(object sender, EventArgs e)
 2         {                     
 3             try
 4             {
 5                 DateTime usetime = Convert.ToDateTime("xxxx/xx/xx 00:00:00");
 6                 DateTime daytime = DateTime.Parse(System.DateTime.Now.ToLongDateString());
 7                 TimeSpan ts = usetime - daytime;
 8                 int day = ts.Days;
 9                 if (day <= 0)
10                 {
11                     if (MessageBox.Show("軟件試用期已到，請註冊後再使用！", "提示", MessageBoxButtons.OK) == DialogResult.OK)
12                     {
13                         Application.Exit();
14                     }
15                 }
16                 else
17                 {
18                   //執行Load的代碼
19                 }
20             }
21             catch { }           
22         }