??? public partial class Page1 : Page
??? {
??????? private static string connStr;
??????? SqlDataReader sdr;
??????? public Page1()
??????? {
??????????? InitializeComponent();
??????????? connStr =?數(shù)據(jù)庫(kù)連接字符串

??????????? SqlDependency.Start(connStr);//傳入連接字符串,啟動(dòng)基于數(shù)據(jù)庫(kù)的監(jiān)聽
??????????? UpdateUI();
??????? }

??????? private void UpdateUI()
??????? {
??????????? using (SqlConnection connection = new SqlConnection(connStr))
??????????? {
??????????????? //依賴是基于某一張表的,而且查詢語(yǔ)句只能是簡(jiǎn)單查詢語(yǔ)句,不能帶top或*,同時(shí)必須指定所有者,即類似[dbo].[]
??????????????? //獲取要監(jiān)控的數(shù)據(jù)內(nèi)容，這里只監(jiān)控一條數(shù)據(jù)
??????????????? using (SqlCommand command = new SqlCommand("select ID,UserID,[Message] From [dbo].[Messages] where ID=2", connection))
??????????????? {
??????????????????? command.CommandType = CommandType.Text;
??????????????????? connection.Open();
??????????????????? SqlDependency dependency = new SqlDependency(command);
??????????????????? //當(dāng)后臺(tái)數(shù)據(jù)庫(kù)發(fā)生變化時(shí)，觸發(fā)該事件
??????????????????? dependency.OnChange += new OnChangeEventHandler(dependency_OnChange);
??????????????????? sdr = command.ExecuteReader();
??????????????????? while (sdr.Read())
??????????????????? {
??????????????????????? //線程安全，使用Dispatch線程更新界面
??????????????????????? DispatchUpdateUI(sdr);
??????????????????? }
??????????????????? sdr.Close();
??????????????? }
??????????? }
??????? }

??????? private void DispatchUpdateUI(SqlDataReader sdr)
??????? {
??????????? try
??????????? {
??????????????? tbxUserID.Dispatcher.Invoke(new UpdatetbxUserDelegate(UpdatetbxUserIDAction));
??????????????? tbxMessage.Dispatcher.Invoke(new UpdatetbxMessageDelegate(UpdatetbxMessageAction));
??????????? }
??????????? catch (Exception ex)
??????????? {

??????????????? throw ex;
??????????? }
??????? }

??????? private delegate void UpdatetbxUserDelegate();
??????? private delegate void UpdatetbxMessageDelegate();

??????? private void UpdatetbxUserIDAction()
??????? {
??????????? tbxUserID.Text = sdr["UserID"].ToString();
??????? }
??????? private void UpdatetbxMessageAction()
??????? {
??????????? tbxMessage.Text = sdr["Message"].ToString();
??????? }
??????? private void dependency_OnChange(object sender, SqlNotificationEventArgs e)
??????? {
??????????? UpdateUI();
??????? }

??? }