StateChangeEventArgs StateChangeEventArgs StateChangeEventArgs StateChangeEventArgs Class

定義

.NET Framework データ プロバイダーの状態変化イベントにデータを提供します。Provides data for the state change event of a .NET Framework data provider.

public ref class StateChangeEventArgs sealed : EventArgs
public sealed class StateChangeEventArgs : EventArgs
type StateChangeEventArgs = class
    inherit EventArgs
Public NotInheritable Class StateChangeEventArgs
Inherits EventArgs
継承
StateChangeEventArgsStateChangeEventArgsStateChangeEventArgsStateChangeEventArgs

次の例は、使用する方法を示します、StateChange内のイベント、SqlConnectionクラス。The following example shows how to use the StateChange event within the SqlConnection class.

// Handler for OnStateChange event.
protected static void OnStateChange(object sender,
    StateChangeEventArgs e)
{
    PrintEventArgs(e);
}

static void Main()
{
    FillDataSet();
}

static private void FillDataSet()
{
    string connectionString = GetConnectionString();
    string queryString =
        "SELECT ProductID, UnitPrice from dbo.Products;";

    // Create a DataAdapter.
    using (SqlDataAdapter dataAdapter =
               new SqlDataAdapter(queryString, connectionString))
    {

        // Add the handlers.
        dataAdapter.SelectCommand.Connection.StateChange
            += new StateChangeEventHandler(OnStateChange);

        // Create a DataSet.
        DataSet dataSet = new DataSet();

        // Fill the DataSet, which fires several StateChange events.
        dataAdapter.Fill(dataSet, 0, 5, "Table");
    }
}

protected static void PrintEventArgs(StateChangeEventArgs args)
{
    Console.WriteLine("StateChangeEventArgs");
    Console.WriteLine("  OriginalState= {0} CurrentState= {1}",
        args.OriginalState, args.CurrentState);
}

static private string GetConnectionString()
{
    // 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";
}
' 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

注釈

使用される、データ、StateChangeのプロパティ、OleDbConnectionStateChangeのプロパティ、SqlConnectionします。The data is used by the StateChange property of the OleDbConnection and the StateChange property of the SqlConnection.

コンストラクター

StateChangeEventArgs(ConnectionState, ConnectionState) StateChangeEventArgs(ConnectionState, ConnectionState) StateChangeEventArgs(ConnectionState, ConnectionState) StateChangeEventArgs(ConnectionState, ConnectionState)

オブジェクトの元の状態と現在の状態が指定されている場合は、StateChangeEventArgs クラスの新しいインスタンスを初期化します。Initializes a new instance of the StateChangeEventArgs class, when given the original state and the current state of the object.

プロパティ

CurrentState CurrentState CurrentState CurrentState

接続の新しい状態を取得します。Gets the new state of the connection. イベントが発生したときは、接続オブジェクトが既に新しい状態になっています。The connection object will be in the new state already when the event is fired.

OriginalState OriginalState OriginalState OriginalState

接続の元の状態を取得します。Gets the original state of the connection.

メソッド

Equals(Object) Equals(Object) Equals(Object) Equals(Object)

指定したオブジェクトが、現在のオブジェクトと等しいかどうかを判断します。Determines whether the specified object is equal to the current object.

(Inherited from Object)
GetHashCode() GetHashCode() GetHashCode() GetHashCode()

既定のハッシュ関数として機能します。Serves as the default hash function.

(Inherited from Object)
GetType() GetType() GetType() GetType()

現在のインスタンスの Type を取得します。Gets the Type of the current instance.

(Inherited from Object)
MemberwiseClone() MemberwiseClone() MemberwiseClone() MemberwiseClone()

現在の Object の簡易コピーを作成します。Creates a shallow copy of the current Object.

(Inherited from Object)
ToString() ToString() ToString() ToString()

現在のオブジェクトを表す文字列を返します。Returns a string that represents the current object.

(Inherited from Object)

適用対象