ListView.SelectedIndices Proprietà

  • Riferimento

Definizione

Spazio dei nomi:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll

Ottiene gli indici degli elementi selezionati nel controllo.

public:
 property System::Windows::Forms::ListView::SelectedIndexCollection ^ SelectedIndices { System::Windows::Forms::ListView::SelectedIndexCollection ^ get(); };
[System.ComponentModel.Browsable(false)]
public System.Windows.Forms.ListView.SelectedIndexCollection SelectedIndices { get; }
[<System.ComponentModel.Browsable(false)>]
member this.SelectedIndices : System.Windows.Forms.ListView.SelectedIndexCollection
Public ReadOnly Property SelectedIndices As ListView.SelectedIndexCollection

Valore della proprietà

ListView.SelectedIndexCollection

Oggetto ListView.SelectedIndexCollection che contiene gli indici degli elementi selezionati. Se non sono stati selezionati elementi, viene restituito un oggetto ListView.SelectedIndexCollection vuoto.

Attributi
BrowsableAttribute

Esempio

Nell'esempio di codice seguente viene illustrato l'uso dei SelectedIndicesmembri , SelectedIndexChangede HeaderStyle e della ListView.SelectedIndexCollection classe . Per eseguire questo esempio, incollare il codice seguente in un modulo contenente un ListView oggetto denominato e un TextBox oggetto denominato TextBox1ListView1 . Chiamare il InitializeListView metodo dal costruttore o Load dal metodo del modulo. Questo esempio richiede che il gestore eventi sia associato correttamente all'evento SelectedIndexChanged .

// 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 );
}

  // 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);
  }

' 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 SelectedIndices property to retrieve and tally the  
// price of the selected menu items.
void ListView1_SelectedIndexChanged_UsingIndices( Object^ /*sender*/, System::EventArgs^ /*e*/ )
{
   ListView::SelectedIndexCollection^ indexes = this->ListView1->SelectedIndices;
   double price = 0.0;
   System::Collections::IEnumerator^ myEnum1 = indexes->GetEnumerator();
   while ( myEnum1->MoveNext() )
   {
      int index = safe_cast<int>(myEnum1->Current);
      price += Double::Parse( this->ListView1->Items[ index ]->SubItems[ 1 ]->Text );
   }

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

// Uses the SelectedIndices property to retrieve and tally the  
// price of the selected menu items.
private void ListView1_SelectedIndexChanged_UsingIndices(
    object sender, System.EventArgs e)
{

    ListView.SelectedIndexCollection indexes = 
        this.ListView1.SelectedIndices;
    
    double price = 0.0;
    foreach ( int index in indexes )
    {
        price += Double.Parse(
            this.ListView1.Items[index].SubItems[1].Text);
    }

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

' Uses the SelectedIndices property to retrieve and tally the price of  
' the selected menu items.
Private Sub ListView1_SelectedIndexChanged_UsingIndices _
    (ByVal sender As Object, ByVal e As System.EventArgs) _
    Handles ListView1.SelectedIndexChanged

    Dim indexes As ListView.SelectedIndexCollection = _
        Me.ListView1.SelectedIndices
    Dim index As Integer
    Dim price As Double = 0.0
    For Each index In indexes
        price += Double.Parse(Me.ListView1.Items(index).SubItems(1).Text)
    Next

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

Commenti

La SelectedIndices proprietà non conterrà indici se la proprietà viene accessibile prima della creazione dell'handle ListView , che in genere si verifica quando viene ListView caricato inizialmente per la visualizzazione nel modulo. È possibile verificare se l'handle viene creato con la IsHandleCreated proprietà . Quando la MultiSelect proprietà è impostata su true, questa proprietà restituisce una raccolta contenente gli indici di tutti gli elementi selezionati nell'oggetto ListView. Per una selezione ListViewsingola, questa proprietà restituisce una raccolta contenente un singolo elemento contenente l'indice dell'unico elemento selezionato nell'oggetto ListView. Per altre informazioni sulle attività che possono essere eseguite con gli elementi della raccolta, vedere ListView.SelectedIndexCollection.

Se si vuole ottenere una raccolta degli elementi selezionati nel ListView controllo, anziché le posizioni di indice degli elementi selezionati, utilizzare la SelectedItems proprietà .

Si applica a

Vedi anche