SqlCeConnection.Open 方法
開啟資料庫連接,且其屬性設定是由 ConnectionString 指定。
命名空間: System.Data.SqlServerCe
組件: System.Data.SqlServerCe (在 System.Data.SqlServerCe.dll 中)
語法
'宣告
<SecurityCriticalAttribute> _
<SecurityTreatAsSafeAttribute> _
Public Overrides Sub Open
'用途
Dim instance As SqlCeConnection
instance.Open()
[SecurityCriticalAttribute]
[SecurityTreatAsSafeAttribute]
public override void Open()
[SecurityCriticalAttribute]
[SecurityTreatAsSafeAttribute]
public:
virtual void Open() override
[<SecurityCriticalAttribute>]
[<SecurityTreatAsSafeAttribute>]
abstract Open : unit -> unit
[<SecurityCriticalAttribute>]
[<SecurityTreatAsSafeAttribute>]
override Open : unit -> unit
public override function Open()
實作
例外狀況
例外狀況 | 條件 |
---|---|
InvalidOperationException | 連接已經開啟。 |
SqlCeException | 當開啟連接時發生的連接層級錯誤。 |
備註
這個方法會建立資料來源的新連接。
注意
如果 SqlCeConnection 超出範圍,就不會關閉。您必須呼叫 Close 或 Dispose 來明確地關閉連接。
範例
下列範例會建立 SqlCeConnection、加以開啟、執行查詢,然後關閉連接。
Dim conn As SqlCeConnection = Nothing
Try
conn = New SqlCeConnection("Data Source = MyDatabase.sdf; Password ='<pwd>'")
conn.Open()
Dim cmd As SqlCeCommand = conn.CreateCommand()
cmd.CommandText = "INSERT INTO Customers ([Customer ID], [Company Name]) Values('NWIND', 'Northwind Traders')"
cmd.ExecuteNonQuery()
Finally
conn.Close()
End Try
SqlCeConnection conn = null;
try
{
conn = new SqlCeConnection("Data Source = MyDatabase.sdf; Password ='<pwd>'");
conn.Open();
SqlCeCommand cmd = conn.CreateCommand();
cmd.CommandText = "INSERT INTO Customers ([Customer ID], [Company Name]) Values('NWIND', 'Northwind Traders')";
cmd.ExecuteNonQuery();
}
finally
{
conn.Close();
}