WebPart.LoadViewState method
會從先前的要求與SaveViewState()方法儲存還原檢視狀態資訊。
Namespace: Microsoft.SharePoint.WebPartPages
Assembly: Microsoft.SharePoint (in Microsoft.SharePoint.dll)
Syntax
'宣告
Protected Overrides Sub LoadViewState ( _
savedState As Object _
)
'用途
Dim savedState As Object
Me.LoadViewState(savedState)
protected override void LoadViewState(
Object savedState
)
參數
savedState
Type: System.ObjectsAn 物件，代表要還原的控制項狀態。
備註
WebPart類別覆寫基底**LoadViewState()**方法，若要實作自訂邏輯，以決定Microsoft SharePoint Foundation網頁組件控制項將其狀態的還原。接著，可能會想要以實作您自己的自訂邏輯，來覆寫WebPart.LoadViewState方法。若要實作您自己的邏輯保存和還原控制項中的 [檢視] 狀態，先SaveViewState()方法會覆寫與撰寫您自己的實作，以儲存您控制項的狀態。然後您可以覆寫LoadViewState方法與撰寫程式碼，以載入已儲存的狀態。
Examples
下列範例會覆寫Microsoft SharePoint Foundation網頁組件控制項的LoadViewState方法。它會建立Object陣列包含savedState參數中傳遞的檢視狀態資訊。然後它會呼叫基底實作LoadViewState方法的第一個索引位置的陣列。最後，範例會將指派儲存為保存的字串變數網頁組件中的第二個索引位置的值。
Protected _persistedString As String = "Default Value"
Protected Overrides Sub LoadViewState(savedState As Object)
Try
Dim viewstate() As Object = Nothing
If Not (savedState Is Nothing) Then
' Load state from the array of objects
' that was saved by SaveViewState.
viewstate = CType(savedState, Object())
MyBase.LoadViewState(viewstate(0))
' Load custom state
If Not (viewstate(1) Is Nothing) Then
Me._persistedString = CStr(viewstate(1))
End If
End If
Catch ex As Exception
' Handle exceptions
End Try
End Sub
protected string _persistedString = "Default Value";
protected override void LoadViewState(object savedState)
{
try
{
object[] viewstate = null;
if (savedState != null)
{
// Load state from the object
// that was saved by SaveViewState.
viewstate = (object[])savedState;
base.LoadViewState(viewstate[0]);
// Load custom state
if (viewstate[1] != null)
this._persistedString = (string)viewstate[1];
}
catch Exception(ex)
{
// Handle exceptions
}
}