StateBag.IsItemDirty(String) StateBag.IsItemDirty(String) StateBag.IsItemDirty(String) StateBag.IsItemDirty(String) Method

Definition

Überprüft ein im StateItem-Objekt gespeichertes StateBag-Objekt, um auszuwerten, ob es seit dem Aufruf von TrackViewState() geändert wurde.Checks a StateItem object stored in the StateBag object to evaluate whether it has been modified since the call to TrackViewState().

public:
 bool IsItemDirty(System::String ^ key);
public bool IsItemDirty (string key);
member this.IsItemDirty : string -> bool
Public Function IsItemDirty (key As String) As Boolean

Parameter

key
String String String String

Der Schlüssel des zu überprüfenden Elements.The key of the item to check.

Gibt zurück

true, wenn das Element geändert wurde, andernfalls false.true if the item has been modified; otherwise, false.

Beispiele

Das folgende Codebeispiel veranschaulicht die Verwendung der IsItemDirty Methode.The following code example demonstrates using the IsItemDirty method.

// Implement the SaveViewState method. If the StateBag
// that stores the MyItem class's view state contains
// a value for the message property and if the value
// has changed since the TrackViewState method was last 
// called, all view state for this class is deleted, 
// using the StateBag.Clear method,and the new value is added.
object IStateManager.SaveViewState()
{
    // Check whether the message property exists in 
    // the ViewState property, and if it does, check
    // whether it has changed since the most recent
    // TrackViewState method call.
    if (!((IDictionary)_viewstate).Contains("message") || _viewstate.IsItemDirty("message"))
    {
        _viewstate.Clear();
        // Add the _message property to the StateBag.
        _viewstate.Add("message", _message);
    }
    return ((IStateManager)_viewstate).SaveViewState();
}

' Implement the SaveViewState method. If the StateBag
' that stores the MyItem class's view state contains
' a value for the message property and if the value
' has changed since the TrackViewState method was last 
' called, all view state for this class is deleted, 
' using the StateBag.Clear method,and the new value is added.
Function SaveViewState() As Object Implements IStateManager.SaveViewState
    ' Check whether the message property exists in 
    ' the ViewState property, and if it does, check
    ' whether it has changed since the most recent
    ' TrackViewState method call.
    If Not CType(_viewstate, IDictionary).Contains("message") OrElse _viewstate.IsItemDirty("message") Then
        _viewstate.Clear()
        ' Add the _message property to the StateBag.
        _viewstate.Add("message", _message)
    End If
    Return CType(_viewstate, IStateManager).SaveViewState()
End Function 'IStateManager.SaveViewState


Hinweise

Diese Methode gibt auch zurück false Wenn die key Parameter ist nicht vorhanden, der StateBag Objekt.This method also returns false if the key parameter does not exist in the StateBag object.

Gilt für:

Siehe auch