StateChangeEventArgs Class
Provides data for the state change event of a .NET Framework data provider.
Assembly: System.Data (in System.Data.dll)
The StateChangeEventArgs type exposes the following members.
| Name | Description | |
|---|---|---|
![]() ![]() | StateChangeEventArgs | Initializes a new instance of the StateChangeEventArgs class, when given the original state and the current state of the object. |
| Name | Description | |
|---|---|---|
![]() ![]() | CurrentState | Gets the new state of the connection. The connection object will be in the new state already when the event is fired. |
![]() ![]() | OriginalState | Gets the original state of the connection. |
| Name | Description | |
|---|---|---|
![]() ![]() | Equals(Object) | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) |
![]() ![]() | Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) |
![]() ![]() | GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
![]() ![]() | GetType | Gets the Type of the current instance. (Inherited from Object.) |
![]() ![]() | MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
![]() ![]() | ToString | Returns a string that represents the current object. (Inherited from Object.) |
The data is used by the StateChange property of the OleDbConnection and the StateChange property of the SqlConnection.
The following example shows how to use the StateChange event within the SqlConnection class.
' Handler for the OnStateChange event.
Private Sub OnStateChange(ByVal sender As Object, _
ByVal e As StateChangeEventArgs)
PrintEventArgs(e)
End Sub
Sub Main()
FillDataSet()
End Sub
Private Sub FillDataSet()
Dim connectionString As String = GetConnectionString()
Dim queryString As String = _
"SELECT ProductID, UnitPrice from dbo.Products;"
' Create a DataAdapter.
Using dataAdapter As New SqlDataAdapter( _
queryString, connectionString)
' Add the handlers.
AddHandler dataAdapter.SelectCommand.Connection.StateChange, _
AddressOf OnStateChange
' Create a DataSet.
Dim dataSet As New DataSet()
' Fill the DataSet, which fires several StateChange events.
dataAdapter.Fill(dataSet, 0, 5, "Table")
End Using
End Sub
Private Sub PrintEventArgs(ByVal args As StateChangeEventArgs)
Console.WriteLine("StateChangeEventArgs")
Console.WriteLine(" OriginalState= {0} CurrentState= {1}", _
args.OriginalState, args.CurrentState)
End Sub
Private Function GetConnectionString() As String
' To avoid storing the connection string in your code,
' you can retrieve it from a configuration file.
Return "Data Source=(local);Initial Catalog=Northwind;" _
& "Integrated Security=true;"
End Function
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.



