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OleDbConnection.Open Method

Opens a database connection with the property settings specified by the ConnectionString.

[Visual Basic]
Public Overridable Sub Open() Implements IDbConnection.Open
[C#]
public virtual void Open();
[C++]
public: virtual void Open();
[JScript]
public function Open();

Implements

IDbConnection.Open

Exceptions

Exception Type Condition
InvalidOperationException The connection is already open.
OleDbException A connection-level error occurred while opening the connection.

Remarks

The OleDbConnection draws an open connection from the connection pool if one is available. Otherwise, it establishes a new connection to the data source.

Note   If the OleDbConnection goes out of scope, it is not closed. Therefore, you must explicitly close the connection by calling Close or Dispose.

Example

[Visual Basic, C#, C++] The following example creates an OleDbConnection, opens it, displays some of its properties, then closes the connection.

[Visual Basic] 
Public Sub CreateOleDbConnection(myConnString As String)
    Dim myConnection As New OleDbConnection(myConnString)
    myConnection.Open()
    MessageBox.Show("ServerVersion: " + myConnection.ServerVersion _
       + ControlChars.Cr + "State: " + myConnection.State.ToString())
    myConnection.Close()
End Sub

[C#] 
public void CreateOleDbConnection(string myConnString) 
{
   OleDbConnection myConnection = new OleDbConnection(myConnString);
   myConnection.Open();
   MessageBox.Show("ServerVersion: " + myConnection.ServerVersion
      + "\nState: " + myConnection.State.ToString());
   myConnection.Close();
}

[C++] 
public:
 void CreateOleDbConnection(String* myConnString) 
 {
    OleDbConnection* myConnection = new OleDbConnection(myConnString);
    myConnection->Open();
    MessageBox::Show(String::Format( S"ServerVersion: {0}\nState: {1}", myConnection->ServerVersion, __box(myConnection->State)));
    myConnection->Close();
 }

[JScript] No example is available for JScript. To view a Visual Basic, C#, or C++ example, click the Language Filter button Language Filter in the upper-left corner of the page.

Requirements

Platforms: Windows 98, Windows NT 4.0, Windows Millennium Edition, Windows 2000, Windows XP Home Edition, Windows XP Professional, Windows Server 2003 family

See Also

OleDbConnection Class | OleDbConnection Members | System.Data.OleDb Namespace | Close

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