UserControl.SaveViewState UserControl.SaveViewState UserControl.SaveViewState UserControl.SaveViewState Method

Определение

Сохраняет любые изменения состояния представления пользовательского элемента управления, произошедшие с момента последней обратной передачи страницы.Saves any user control view-state changes that have occurred since the last page postback.

protected:
 override System::Object ^ SaveViewState();
protected override object SaveViewState ();
override this.SaveViewState : unit -> obj
Protected Overrides Function SaveViewState () As Object

Возвраты

Возвращает текущее состояние представления пользовательского элемента управления.Returns the user control's current view state. Если состояние представления не связано с элементом управления, то метод возвращает значение null.If there is no view state associated with the control, it returns null.

Примеры

В следующем примере показан пользовательский элемент управления, управляющий состоянием представления с LoadViewState помощью SaveViewState методов и.The following example demonstrates a user control that manages its view state using the LoadViewState and SaveViewState methods.

public string UserText
{
    get
    {
        return (string)ViewState["usertext"];
    }
    set
    {
        ViewState["usertext"] = value;
    }
}
public string PasswordText
{
    get
    {
        return (string)ViewState["passwordtext"];
    }
    set
    {
        ViewState["passwordtext"] = value;
    }
}

[System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")] 
protected override void LoadViewState(object savedState) 
{
    object[] totalState = null;	   
    if (savedState != null)
    {
        totalState = (object[])savedState;
        if (totalState.Length != 3)
        {
            // Throw an appropriate exception.
        }
        // Load base state.
        base.LoadViewState(totalState[0]);
        // Load extra information specific to this control.
        if (totalState != null && totalState[1] != null && totalState[2] != null)
        {
            UserText = (string)totalState[1];
            PasswordText = (string)totalState[2];
        }
    }

}

[System.Security.Permissions.PermissionSet(System.Security.Permissions.SecurityAction.Demand, Name="FullTrust")] 
protected override object SaveViewState()
{
    object baseState = base.SaveViewState();
    object[] totalState = new object[3];
    totalState[0] = baseState;
    totalState[1] = user.Text;
    totalState[2] = password.Text;
    return totalState;
}
   
    Public Property UserText() As String

        Get
            Return CStr(ViewState("usertext"))
        End Get
        Set(ByVal value As String)
            ViewState("usertext") = value
        End Set

    End Property
   
    Public Property PasswordText() As String

        Get
            Return CStr(ViewState("passwordtext"))
        End Get
        Set(ByVal value As String)
            ViewState("passwordtext") = value
        End Set

    End Property
   
    <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
    Protected Overrides Sub LoadViewState(ByVal savedState As Object)

        Dim totalState As Object() = Nothing
        If Not (savedState Is Nothing) Then
            totalState = CType(savedState, Object())
            If totalState.Length <> 3 Then
                ' Throw an appropriate exception.
            End If
            ' Load base state.
            MyBase.LoadViewState(totalState(0))
            ' Load extra information specific to this control.
            If Not (totalState Is Nothing) AndAlso Not (totalState(1) Is Nothing) AndAlso Not (totalState(2) Is Nothing) Then
                UserText = CStr(totalState(1))
                PasswordText = CStr(totalState(2))
            End If
        End If

    End Sub
     
    <System.Security.Permissions.PermissionSetAttribute(System.Security.Permissions.SecurityAction.Demand, Name:="FullTrust")> _
    Protected Overrides Function SaveViewState() As Object

        Dim baseState As Object = MyBase.SaveViewState()
        Dim totalState(2) As Object
        totalState(0) = baseState
        totalState(1) = user.Text
        totalState(2) = password.Text
        Return totalState

    End Function
End Class 

Комментарии

В общем случае нет необходимости вызывать этот метод.In general, you do not need to call this method. Однако, если пользовательские данные хранятся в состоянии представления, этот метод можно переопределить.However, if you store custom information in view state, you can override this method to do so.

Применяется к

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