CurrencyManager.ItemChanged Událost

Definice

Vyvolá se v případě, že byla aktuální položka změněna.Occurs when the current item has been altered.

public:
 event System::Windows::Forms::ItemChangedEventHandler ^ ItemChanged;
public event System.Windows.Forms.ItemChangedEventHandler ItemChanged;
member this.ItemChanged : System.Windows.Forms.ItemChangedEventHandler 
Public Custom Event ItemChanged As ItemChangedEventHandler 

Event Type

ItemChangedEventHandler

Příklady

Následující příklad kódu přidá obslužné rutiny událostí pro ItemChanged PositionChanged události a.The following code example adds event handlers for the ItemChanged and PositionChanged events.

void BindControl( DataTable^ myTable )
{
   
   // Bind A TextBox control to a DataTable column in a DataSet.
   textBox1->DataBindings->Add( "Text", myTable, "CompanyName" );
   
   // Specify the CurrencyManager for the DataTable.
   myCurrencyManager = dynamic_cast<CurrencyManager^>(this->BindingContext[myTable, ""]);
   
   // Add event handlers.
   myCurrencyManager->ItemChanged += gcnew ItemChangedEventHandler( this, &Form1::CurrencyManager_ItemChanged );
   myCurrencyManager->PositionChanged += gcnew EventHandler( this, &Form1::CurrencyManager_PositionChanged );
   
   // Set the initial Position of the control.
   myCurrencyManager->Position = 0;
}

void CurrencyManager_PositionChanged( Object^ sender, System::EventArgs^ /*e*/ )
{
   CurrencyManager^ myCurrencyManager = dynamic_cast<CurrencyManager^>(sender);
   Console::WriteLine( "Position Changed {0}", myCurrencyManager->Position );
}

void CurrencyManager_ItemChanged( Object^ sender, System::Windows::Forms::ItemChangedEventArgs^ /*e*/ )
{
   CurrencyManager^ myCurrencyManager = dynamic_cast<CurrencyManager^>(sender);
   Console::WriteLine( "Item Changed {0}", myCurrencyManager->Position );
}

   private void BindControl(DataTable myTable)
   {
       // Bind A TextBox control to a DataTable column in a DataSet.
       textBox1.DataBindings.Add("Text", myTable, "CompanyName");
       // Specify the CurrencyManager for the DataTable.
       myCurrencyManager = (CurrencyManager)this.BindingContext[myTable, ""];
       // Add event handlers.
       myCurrencyManager.ItemChanged+=
       new ItemChangedEventHandler(CurrencyManager_ItemChanged);
       myCurrencyManager.PositionChanged+= 
       new EventHandler(CurrencyManager_PositionChanged);
       // Set the initial Position of the control.
       myCurrencyManager.Position = 0;
   }

   private void CurrencyManager_PositionChanged(object sender, System.EventArgs e){
       CurrencyManager myCurrencyManager = (CurrencyManager) sender;
       Console.WriteLine("Position Changed " + myCurrencyManager.Position);
   }

   private void CurrencyManager_ItemChanged(object sender, System.Windows.Forms.ItemChangedEventArgs e){
       CurrencyManager myCurrencyManager = (CurrencyManager) sender;
       Console.WriteLine("Item Changed " + myCurrencyManager.Position);
   }
Private Sub BindControl(myTable As DataTable)
    ' Bind A TextBox control to a DataTable column in a DataSet.
    textBox1.DataBindings.Add("Text", myTable, "CompanyName")
    ' Specify the CurrencyManager for the DataTable.
    myCurrencyManager = CType(Me.BindingContext(myTable, ""), CurrencyManager)
    ' Add event handlers.
    AddHandler myCurrencyManager.ItemChanged, AddressOf CurrencyManager_ItemChanged
    AddHandler myCurrencyManager.PositionChanged, AddressOf CurrencyManager_PositionChanged
    ' Set the initial Position of the control.
    myCurrencyManager.Position = 0
End Sub


Private Sub CurrencyManager_PositionChanged(sender As Object, e As System.EventArgs)
    Dim myCurrencyManager As CurrencyManager = CType(sender, CurrencyManager)
    Console.WriteLine(("Position Changed " & myCurrencyManager.Position))
End Sub


Private Sub CurrencyManager_ItemChanged(sender As Object, e As System.Windows.Forms.ItemChangedEventArgs)
    Dim myCurrencyManager As CurrencyManager = CType(sender, CurrencyManager)
    Console.WriteLine(("Item Changed " & myCurrencyManager.Position))
End Sub

Poznámky

K ItemChanged události dojde, když uživatel zavolá ResumeBinding metodu nebo SuspendBinding .The ItemChanged event will occur when the user calls the ResumeBinding or SuspendBinding method.

K ItemChanged události dochází pouze v případě, že se položka změnila nějakým způsobem.The ItemChanged event occurs only when the item itself has been changed in some manner. Například pokud se hodnota položky změní z 10 na 42, dojde k události.For example, if the value of an item is changed from 10 to 42, the event will occur. Nemělo by se zaměňovat s PositionChanged událostí, kde byla položka změněna na novou položku.This should not be confused with the PositionChanged event where the item has been changed to a new item.

K události dojde také v případě, že se změní podkladová data.The event will also occur if the underlying data changes. Například pokud změníte hodnotu a DataRowView , ItemChanged dojde k události.For example, if you change the value of a DataRowView, the ItemChanged event will occur.

Poznámka

Pokud vytváříte vlastní ovládací prvek, který používá CurrencyManager , použijte IBindingList.ListChanged místo CurrencyManager.ItemChanged události.If you are creating your own control that uses the CurrencyManager, you should use the IBindingList.ListChanged instead of the CurrencyManager.ItemChanged event. ListChangedTypeVlastnost ListChangedEventArgs umožňuje určit typ akce, ke které došlo.The ListChangedType property of the ListChangedEventArgs enables you to determine the type of action that has occurred.

Další informace o zpracování událostí naleznete v tématu manipulace a vyvolávání událostí.For more information about handling events, see Handling and Raising Events.

Platí pro

Viz také