ListView.SelectedItems-Eigenschaft
Ruft die im Steuerelement ausgewählten Elemente ab.
Namespace: System.Windows.Forms
Assembly: System.Windows.Forms (in system.windows.forms.dll)
Syntax
'Declaration
Public ReadOnly Property SelectedItems As SelectedListViewItemCollection
'Usage
Dim instance As ListView
Dim value As SelectedListViewItemCollection
value = instance.SelectedItems
public SelectedListViewItemCollection SelectedItems { get; }
public:
property SelectedListViewItemCollection^ SelectedItems {
SelectedListViewItemCollection^ get ();
}
/** @property */
public SelectedListViewItemCollection get_SelectedItems ()
public function get SelectedItems () : SelectedListViewItemCollection
Eigenschaftenwert
Eine ListView.SelectedListViewItemCollection, die die im Steuerelement ausgewählten Elemente enthält. Wenn gegenwärtig keine Elemente ausgewählt sind, wird eine leere ListView.SelectedListViewItemCollection zurückgegeben.
Hinweise
Die SelectedItems-Eigenschaft enthält keine Elemente, wenn auf die Eigenschaft zugegriffen wird, bevor das ListView-Handle erstellt wird. Dies tritt typischerweise ein, wenn ListView erstmals zum Anzeigen im Formular geladen wird. Sie können überprüfen, ob das Handle mithilfe der IsHandleCreated-Eigenschaft erstellt wird. Wenn die MultiSelect-Eigenschaft auf true festgelegt ist, gibt diese Eigenschaft eine Auflistung mit den in der ListView ausgewählten Elementen zurück. Für eine ListView mit einfacher Auswahl gibt diese Eigenschaft eine Auflistung zurück, die das einzige in der ListView ausgewählte Element enthält. Weitere Informationen zu den Aufgaben, die mit den Elementen in der Auflistung ausgeführt werden können, finden Sie unter ListView.SelectedListViewItemCollection.
Wenn Sie nicht die ausgewählten Elemente, sondern eine Auflistung der Indexpositionen in der ListView.ListViewItemCollection für die im ListView-Steuerelement ausgewählten Elemente abrufen möchten, verwenden Sie die SelectedIndices-Eigenschaft.
Beispiel
Im folgenden Codebeispiel wird veranschaulicht, wie die SelectedItems, das SelectedIndexChanged-Ereignis, die HeaderStyle-Member und die ListView.SelectedListViewItemCollection-Klasse verwendet werden. Fügen Sie zum Ausführen dieses Beispiels den folgenden Code in ein Formular ein, das das ListView-Objekt ListView1 und die TextBoxTextBox1 enthält. Rufen Sie die InitializeListView-Methode aus dem Konstruktor des Formulars oder die Load-Methode auf. In diesem Beispiel muss der Ereignishandler dem SelectedIndexChanged-Ereignis richtig 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
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-Klasse
ListView-Member
System.Windows.Forms-Namespace
ListView.SelectedListViewItemCollection
ListView.SelectedIndices-Eigenschaft