ListView.SelectedListViewItemCollection-Klasse

Stellt die Auflistung ausgewählter Elemente in einem Listenansicht-Steuerelement dar.

Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in system.windows.forms.dll)

Syntax

'Declaration
Public Class SelectedListViewItemCollection
    Implements IList, ICollection, IEnumerable
'Usage
Dim instance As SelectedListViewItemCollection

public class SelectedListViewItemCollection : IList, ICollection, IEnumerable

public ref class SelectedListViewItemCollection : IList, ICollection, IEnumerable

public class SelectedListViewItemCollection implements IList, ICollection, 
    IEnumerable

public class SelectedListViewItemCollection implements IList, ICollection, 
    IEnumerable

Hinweise

Eine ListView.SelectedListViewItemCollection speichert die ausgewählten Elemente in einem ListView-Steuerelement. Die in der ListView.SelectedListViewItemCollection gespeicherten Elemente sind in der ListView.ListViewItemCollection enthaltene Elemente. Die ListView.ListViewItemCollection enthält alle in der ListView angezeigten Elemente.

In der folgenden Tabelle wird anhand eines Beispiels gezeigt, wie die ListView.ListViewItemCollection die Elemente der ListView sowie deren Auswahlzustand in einem Muster-ListView-Steuerelement speichert.

Index	Element	Auswahlzustand in ListView
0	Element1	Nicht ausgewählt
1	Element2	Ausgewählt
2	Element3	Nicht ausgewählt
3	Element4	Ausgewählt
4	Element5	Ausgewählt

Auf der Grundlage des Beispiels für die ListView.ListViewItemCollection in der vorausgegangenen Tabelle veranschaulicht die folgende Tabelle die Darstellung der ListView.SelectedListViewItemCollection.

Index	Ausgewähltes Element in der ListViewItemCollection
0	Element2
1	Element4
2	Element5

Mit den Methoden und Eigenschaften dieser Klasse können Sie eine Vielzahl von Aufgaben mit der Auflistung durchführen. Mit der Contains-Methode können Sie bestimmen, ob ein Element der ListView.ListViewItemCollection-Klasse ein Member der ListView.SelectedListViewItemCollection ist. Wenn Sie festgestellt haben, dass sich das Element in der Auflistung befindet, können Sie mithilfe der IndexOf-Methode die Elementposition in der ListView.SelectedListViewItemCollection bestimmen.

Beispiel

Das folgende Codebeispiel veranschaulicht, wie SelectedItems, das SelectedIndexChanged-Ereignis, HeaderStyle-Member und die ListView.SelectedListViewItemCollection-Klasse verwendet werden. Zum Ausführen des Beispiels fügen Sie den folgenden Code in ein Formular ein, das ein ListView-Objekt mit dem Namen ListView1 und eine TextBox mit dem Namen TextBox1 enthält. Rufen Sie die InitializeListView-Methode aus dem Konstruktor oder dem Load-Ereignishandler des Formulars auf. Bei diesem Beispiel muss der Ereignishandler dem SelectedIndexChanged-Ereignis ordnungsgemäß zugeordnet sein.

    ' This method adds two columns to the ListView, setting the Text 
    ' and TextAlign, and Width properties of each ColumnHeader.  The 
    ' HeaderStyle property is set to NonClickable since the ColumnClick 
    ' event is not handled.  Finally the method adds ListViewItems and 
    ' SubItems to each column.
    Private Sub InitializeListView()
        Me.ListView1 = New System.Windows.Forms.ListView
        Me.ListView1.BackColor = System.Drawing.SystemColors.Control
        Me.ListView1.Dock = System.Windows.Forms.DockStyle.Top
        Me.ListView1.Location = New System.Drawing.Point(0, 0)
        Me.ListView1.Name = "ListView1"
        Me.ListView1.Size = New System.Drawing.Size(292, 130)
        Me.ListView1.TabIndex = 0
        Me.ListView1.View = System.Windows.Forms.View.Details
        Me.ListView1.MultiSelect = True
        Me.ListView1.HideSelection = False
        ListView1.HeaderStyle = ColumnHeaderStyle.Nonclickable
        Dim columnHeader1 As New ColumnHeader
        With columnHeader1
            .Text = "Breakfast Item"
            .TextAlign = HorizontalAlignment.Left
            .Width = 146
        End With
        Dim columnHeader2 As New ColumnHeader
        With columnHeader2
            .Text = "Price Each"
            .TextAlign = HorizontalAlignment.Center
            .Width = 142
        End With

        Me.ListView1.Columns.Add(columnHeader1)
        Me.ListView1.Columns.Add(columnHeader2)
        Dim foodList() As String = New String() {"Juice", "Coffee", _
            "Cereal & Milk", "Fruit Plate", "Toast & Jelly", _
            "Bagel & Cream Cheese"}
        Dim foodPrice() As String = New String() {"1.09", "1.09", _
            "2.19", "2.49", "1.49", "1.49"}
        Dim count As Integer
        For count = 0 To foodList.Length - 1
            Dim listItem As New ListViewItem(foodList(count))
            listItem.SubItems.Add(foodPrice(count))
            ListView1.Items.Add(listItem)
        Next
        Me.Controls.Add(Me.ListView1)
    End Sub

...
    ' Uses the SelectedItems property to retrieve and tally the price 
    ' of the selected menu items.
    Private Sub ListView1_SelectedIndexChanged_UsingItems _
        (ByVal sender As Object, ByVal e As System.EventArgs) _
        Handles ListView1.SelectedIndexChanged

        Dim breakfast As ListView.SelectedListViewItemCollection = _
            Me.ListView1.SelectedItems
        Dim item As ListViewItem
        Dim price As Double = 0.0
        For Each item In breakfast
            price += Double.Parse(item.SubItems(1).Text)
        Next

        ' Output the price to TextBox1.
        TextBox1.Text = CType(price, String)
    End Sub

 // This method adds two columns to the ListView, setting the Text 
    // and TextAlign, and Width properties of each ColumnHeader.  The 
    // HeaderStyle property is set to NonClickable since the ColumnClick 
    // event is not handled.  Finally the method adds ListViewItems and 
    // SubItems to each column.
    private void InitializeListView()
    {
        this.ListView1 = new System.Windows.Forms.ListView();
        this.ListView1.BackColor = System.Drawing.SystemColors.Control;
        this.ListView1.Dock = System.Windows.Forms.DockStyle.Top;
        this.ListView1.Location = new System.Drawing.Point(0, 0);
        this.ListView1.Name = "ListView1";
        this.ListView1.Size = new System.Drawing.Size(292, 130);
        this.ListView1.TabIndex = 0;
        this.ListView1.View = System.Windows.Forms.View.Details;
        this.ListView1.MultiSelect = true;
        this.ListView1.HideSelection = false;
        this.ListView1.HeaderStyle = ColumnHeaderStyle.Nonclickable;
        
        ColumnHeader columnHeader1 = new ColumnHeader();
        columnHeader1.Text = "Breakfast Item";
        columnHeader1.TextAlign = HorizontalAlignment.Left;
        columnHeader1.Width = 146;

        ColumnHeader columnHeader2 = new ColumnHeader();
        columnHeader2.Text = "Price Each";
        columnHeader2.TextAlign = HorizontalAlignment.Center;
        columnHeader2.Width = 142;
  
        this.ListView1.Columns.Add(columnHeader1);
        this.ListView1.Columns.Add(columnHeader2);

        string[] foodList = new string[]{"Juice", "Coffee", 
            "Cereal & Milk", "Fruit Plate", "Toast & Jelly", 
            "Bagel & Cream Cheese"};
        string[] foodPrice = new string[]{"1.09", "1.09", "2.19", 
            "2.49", "1.49", "1.49"};
        
        for(int count=0; count < foodList.Length; count++)
        {
            ListViewItem listItem = new ListViewItem(foodList[count]);
            listItem.SubItems.Add(foodPrice[count]);
            ListView1.Items.Add(listItem);
        }
        this.Controls.Add(ListView1);
    }
    

...
   // Uses the SelectedItems property to retrieve and tally the price 
    // of the selected menu items.
    private void ListView1_SelectedIndexChanged_UsingItems(
        object sender, System.EventArgs e)
    {

        ListView.SelectedListViewItemCollection breakfast = 
            this.ListView1.SelectedItems;
        
        double price = 0.0;
        foreach ( ListViewItem item in breakfast )
        {
            price += Double.Parse(item.SubItems[1].Text);
        }

        // Output the price to TextBox1.
        TextBox1.Text = price.ToString();
    }

   // This method adds two columns to the ListView, setting the Text 
   // and TextAlign, and Width properties of each ColumnHeader.  The 
   // HeaderStyle property is set to NonClickable since the ColumnClick 
   // event is not handled.  Finally the method adds ListViewItems and 
   // SubItems to each column.
   void InitializeListView()
   {
      this->ListView1 = gcnew System::Windows::Forms::ListView;
      this->ListView1->BackColor = System::Drawing::SystemColors::Control;
      this->ListView1->Dock = System::Windows::Forms::DockStyle::Top;
      this->ListView1->Location = System::Drawing::Point( 0, 0 );
      this->ListView1->Name = "ListView1";
      this->ListView1->Size = System::Drawing::Size( 292, 130 );
      this->ListView1->TabIndex = 0;
      this->ListView1->View = System::Windows::Forms::View::Details;
      this->ListView1->MultiSelect = true;
      this->ListView1->HideSelection = false;
      this->ListView1->HeaderStyle = ColumnHeaderStyle::Nonclickable;
      ColumnHeader^ columnHeader1 = gcnew ColumnHeader;
      columnHeader1->Text = "Breakfast Item";
      columnHeader1->TextAlign = HorizontalAlignment::Left;
      columnHeader1->Width = 146;
      ColumnHeader^ columnHeader2 = gcnew ColumnHeader;
      columnHeader2->Text = "Price Each";
      columnHeader2->TextAlign = HorizontalAlignment::Center;
      columnHeader2->Width = 142;
      this->ListView1->Columns->Add( columnHeader1 );
      this->ListView1->Columns->Add( columnHeader2 );
      array<String^>^foodList = {"Juice","Coffee","Cereal & Milk","Fruit Plate","Toast & Jelly","Bagel & Cream Cheese"};
      array<String^>^foodPrice = {"1.09","1.09","2.19","2.49","1.49","1.49"};
      for ( int count = 0; count < foodList->Length; count++ )
      {
         ListViewItem^ listItem = gcnew ListViewItem( foodList[ count ] );
         listItem->SubItems->Add( foodPrice[ count ] );
         ListView1->Items->Add( listItem );

      }
      this->Controls->Add( ListView1 );
   }

...
   // Uses the SelectedItems property to retrieve and tally the price 
   // of the selected menu items.
   void ListView1_SelectedIndexChanged_UsingItems( Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      ListView::SelectedListViewItemCollection^ breakfast = this->ListView1->SelectedItems;
      double price = 0.0;
      System::Collections::IEnumerator^ myEnum = breakfast->GetEnumerator();
      while ( myEnum->MoveNext() )
      {
         ListViewItem^ item = safe_cast<ListViewItem^>(myEnum->Current);
         price += Double::Parse( item->SubItems[ 1 ]->Text );
      }

      // Output the price to TextBox1.
      TextBox1->Text = price.ToString();
   }

    // This method adds two columns to the ListView, setting the Text 
    // and TextAlign, and Width properties of each ColumnHeader.  The 
    // HeaderStyle property is set to NonClickable since the ColumnClick 
    // event is not handled.  Finally the method adds ListViewItems and 
    // SubItems to each column.
    private void InitializeListView()
    {
        this.listView1 = new System.Windows.Forms.ListView();
        this.listView1.set_BackColor(
            System.Drawing.SystemColors.get_Control());
        this.listView1.set_Dock(System.Windows.Forms.DockStyle.Top);
        this.listView1.set_Location(new System.Drawing.Point(0, 0));
        this.listView1.set_Name("listView1");
        this.listView1.set_Size(new System.Drawing.Size(292, 130));
        this.listView1.set_TabIndex(0);
        this.listView1.set_View(System.Windows.Forms.View.Details);
        this.listView1.set_MultiSelect(true);
        this.listView1.set_HideSelection(false);
        this.listView1.set_HeaderStyle(ColumnHeaderStyle.Nonclickable);

        ColumnHeader columnHeader1 = new ColumnHeader();
        columnHeader1.set_Text("Breakfast Item");
        columnHeader1.set_TextAlign(HorizontalAlignment.Left);
        columnHeader1.set_Width(146);

        ColumnHeader columnHeader2 = new ColumnHeader();
        columnHeader2.set_Text("Price Each");
        columnHeader2.set_TextAlign(HorizontalAlignment.Center);
        columnHeader2.set_Width(142);

        this.listView1.get_Columns().Add(columnHeader1);
        this.listView1.get_Columns().Add(columnHeader2);

        String foodList[] = new String[] { "Juice", "Coffee", "Cereal & Milk",
            "Fruit Plate", "Toast & Jelly", "Bagel & Cream Cheese" };
        String foodPrice[] = new String[] { "1.09", "1.09", "2.19", "2.49",
            "1.49", "1.49" };

        for (int count = 0; count < foodList.get_Length(); count++) {
            ListViewItem listItem = new ListViewItem(
                foodList.get_Item(count).ToString());
            listItem.get_SubItems().Add(foodPrice.get_Item(count).ToString());
            listView1.get_Items().Add(listItem);
        }
        this.get_Controls().Add(listView1);
    } //InitializeListView

...
    // Uses the SelectedItems property to retrieve and tally the price 
    // of the selected menu items.
    private void listView1_SelectedIndexChanged_UsingItems(Object sender, 
        System.EventArgs e)
    {
        ListView.SelectedListViewItemCollection breakfast = 
            this.listView1.get_SelectedItems();

        double price = 0.0;
        for (int iCtr = 0; iCtr < breakfast.get_Count(); iCtr++) {
            ListViewItem item = breakfast.get_Item(iCtr);
            price += System.Double.Parse(item.get_SubItems().get_Item(1).
                get_Text().ToString());
        }
        // Output the price to textBox1.
        textBox1.set_Text(System.Convert.ToString(price));
    } //listView1_SelectedIndexChanged_UsingItems

Vererbungshierarchie

System.Object
  System.Windows.Forms.ListView.SelectedListViewItemCollection

Threadsicherheit

Alle öffentlichen statischen (Shared in Visual Basic) Member dieses Typs sind threadsicher. Bei Instanzmembern ist die Threadsicherheit nicht gewährleistet.

Plattformen

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile für Pocket PC, Windows Mobile für Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition

.NET Framework unterstützt nicht alle Versionen sämtlicher Plattformen. Eine Liste der unterstützten Versionen finden Sie unter Systemanforderungen.

Versionsinformationen

.NET Framework

Unterstützt in: 2.0, 1.1, 1.0

Siehe auch

Referenz

ListView.SelectedListViewItemCollection-Member
System.Windows.Forms-Namespace