ListBox.ObjectCollection.AddRange Metoda

Definicja

Dodaje grupę elementów do listy elementów dla elementu ListBox .Adds a group of items to the list of items for a ListBox.

Przeciążenia

AddRange(Object[])

Dodaje tablicę elementów do listy elementów dla elementu ListBox .Adds an array of items to the list of items for a ListBox.

AddRange(ListBox+ObjectCollection)

Dodaje elementy istniejącej ListBox.ObjectCollection do listy elementów w ListBox .Adds the items of an existing ListBox.ObjectCollection to the list of items in a ListBox.

AddRange(Object[])

Dodaje tablicę elementów do listy elementów dla elementu ListBox .Adds an array of items to the list of items for a ListBox.

public:
 void AddRange(cli::array <System::Object ^> ^ items);
public void AddRange (object[] items);
member this.AddRange : obj[] -> unit
Public Sub AddRange (items As Object())

Parametry

items
Object[]

Tablica obiektów, które mają zostać dodane do listy.An array of objects to add to the list.

Wyjątki

.NET 5,0 i nowsze: items is null ..NET 5.0 and later: items is null.

Przykłady

Poniższy przykład kodu demonstruje właociciela ListBox przez ustawienie DrawMode właściwości na OwnerDrawVariable wartość i obsługę DrawItem MeasureItem zdarzeń i.The following code example demonstrates an owner-drawn ListBox by setting the DrawMode property to the OwnerDrawVariable value and handling the DrawItem and MeasureItem events. Przedstawiono w nim również ustawienia BorderStyle i ScrollAlwaysVisible właściwości oraz przy użyciu AddRange metody.It also demonstrates setting the BorderStyle and ScrollAlwaysVisible properties and using the AddRange method.

Aby uruchomić ten przykład, wklej go do pustego formularza, który importuje System.Drawing przestrzeń nazw i System.Windows.Forms przestrzeń nazw.To run this example, paste it into an empty form that imports the System.Drawing namespace and the System.Windows.Forms namespace. Wywołanie InitializeOwnerDrawnListBox z konstruktora lub Load metody formularza.Call InitializeOwnerDrawnListBox from the form's constructor or Load method.

internal:
   System::Windows::Forms::ListBox^ ListBox1;

private:
   void InitializeOwnerDrawnListBox()
   {
      this->ListBox1 = gcnew System::Windows::Forms::ListBox;
      
      // Set the location and size.
      ListBox1->Location = Point(20,20);
      ListBox1->Size = System::Drawing::Size( 240, 240 );
      
      // Populate the ListBox.ObjectCollection property 
      // with several strings, using the AddRange method.
      array<Object^>^temp0 = {"System.Windows.Forms","System.Drawing","System.Xml","System.Net","System.Runtime.Remoting","System.Web"};
      this->ListBox1->Items->AddRange( temp0 );
      
      // Turn off the scrollbar.
      ListBox1->ScrollAlwaysVisible = false;
      
      // Set the border style to a single, flat border.
      ListBox1->BorderStyle = BorderStyle::FixedSingle;
      
      // Set the DrawMode property to the OwnerDrawVariable value. 
      // This means the MeasureItem and DrawItem events must be 
      // handled.
      ListBox1->DrawMode = DrawMode::OwnerDrawVariable;
      ListBox1->MeasureItem += gcnew MeasureItemEventHandler( this, &Form1::ListBox1_MeasureItem );
      ListBox1->DrawItem += gcnew DrawItemEventHandler( this, &Form1::ListBox1_DrawItem );
      this->Controls->Add( this->ListBox1 );
   }

   // Handle the DrawItem event for an owner-drawn ListBox.
   void ListBox1_DrawItem( Object^ /*sender*/, DrawItemEventArgs^ e )
   {
      // If the item is the selected item, then draw the rectangle
      // filled in blue. The item is selected when a bitwise And  
      // of the State property and the DrawItemState.Selected 
      // property is true.
      if ( (e->State & DrawItemState::Selected) == DrawItemState::Selected )
      {
         e->Graphics->FillRectangle( Brushes::CornflowerBlue, e->Bounds );
      }
      else
      {
         
         // Otherwise, draw the rectangle filled in beige.
         e->Graphics->FillRectangle( Brushes::Beige, e->Bounds );
      }
      
      // Draw a rectangle in blue around each item.
      e->Graphics->DrawRectangle( Pens::Blue, e->Bounds );
      
      // Draw the text in the item.
      e->Graphics->DrawString( ListBox1->Items[ e->Index ]->ToString(), this->Font, Brushes::Black, (float)e->Bounds.X, (float)e->Bounds.Y );
      
      // Draw the focus rectangle around the selected item.
      e->DrawFocusRectangle();
   }


   // Handle the MeasureItem event for an owner-drawn ListBox.
   void ListBox1_MeasureItem( Object^ sender, MeasureItemEventArgs^ e )
   {
      
      // Cast the sender object back to ListBox type.
      ListBox^ theListBox = dynamic_cast<ListBox^>(sender);
      
      // Get the string contained in each item.
      String^ itemString = dynamic_cast<String^>(theListBox->Items[ e->Index ]);
      
      // Split the string at the " . "  character.
      array<Char>^temp1 = {'.'};
      array<String^>^resultStrings = itemString->Split( temp1 );
      
      // If the string contains more than one period, increase the 
      // height by ten pixels; otherwise, increase the height by 
      // five pixels.
      if ( resultStrings->Length > 2 )
      {
         e->ItemHeight += 10;
      }
      else
      {
         e->ItemHeight += 5;
      }
   }
internal System.Windows.Forms.ListBox ListBox1;

private void InitializeOwnerDrawnListBox()
{
    this.ListBox1 = new System.Windows.Forms.ListBox();

    // Set the location and size.
    ListBox1.Location = new Point(20, 20);
    ListBox1.Size = new Size(240, 240);

    // Populate the ListBox.ObjectCollection property 
    // with several strings, using the AddRange method.
    this.ListBox1.Items.AddRange(new object[]{"System.Windows.Forms", 
        "System.Drawing", "System.Xml", "System.Net", "System.Runtime.Remoting", 
        "System.Web"});

    // Turn off the scrollbar.
    ListBox1.ScrollAlwaysVisible = false;

    // Set the border style to a single, flat border.
    ListBox1.BorderStyle = BorderStyle.FixedSingle;

    // Set the DrawMode property to the OwnerDrawVariable value. 
    // This means the MeasureItem and DrawItem events must be 
    // handled.
    ListBox1.DrawMode = DrawMode.OwnerDrawVariable;
    ListBox1.MeasureItem += 
        new MeasureItemEventHandler(ListBox1_MeasureItem);
    ListBox1.DrawItem += new DrawItemEventHandler(ListBox1_DrawItem);
    this.Controls.Add(this.ListBox1);
}

// Handle the DrawItem event for an owner-drawn ListBox.
private void ListBox1_DrawItem(object sender, DrawItemEventArgs e)
{

    // If the item is the selected item, then draw the rectangle
    // filled in blue. The item is selected when a bitwise And  
    // of the State property and the DrawItemState.Selected 
    // property is true.
    if ((e.State & DrawItemState.Selected) == DrawItemState.Selected)
    {
        e.Graphics.FillRectangle(Brushes.CornflowerBlue, e.Bounds);
    }
    else
    {
        // Otherwise, draw the rectangle filled in beige.
        e.Graphics.FillRectangle(Brushes.Beige, e.Bounds);
    }

    // Draw a rectangle in blue around each item.
    e.Graphics.DrawRectangle(Pens.Blue, e.Bounds);

    // Draw the text in the item.
    e.Graphics.DrawString(ListBox1.Items[e.Index].ToString(),
        this.Font, Brushes.Black, e.Bounds.X, e.Bounds.Y);

    // Draw the focus rectangle around the selected item.
    e.DrawFocusRectangle();
}

// Handle the MeasureItem event for an owner-drawn ListBox.
private void ListBox1_MeasureItem(object sender, 
    MeasureItemEventArgs e)
{

    // Cast the sender object back to ListBox type.
    ListBox theListBox = (ListBox) sender;

    // Get the string contained in each item.
    string itemString = (string) theListBox.Items[e.Index];

    // Split the string at the " . "  character.
    string[] resultStrings = itemString.Split('.');

    // If the string contains more than one period, increase the 
    // height by ten pixels; otherwise, increase the height by 
    // five pixels.
    if (resultStrings.Length>2)
    {
        e.ItemHeight += 10;
    }
    else
    {
        e.ItemHeight += 5;
    }
}

Friend WithEvents ListBox1 As System.Windows.Forms.ListBox

Private Sub InitializeOwnerDrawnListBox()
    Me.ListBox1 = New System.Windows.Forms.ListBox

    ' Set the location and size.
    ListBox1.Location = New Point(20, 20)
    ListBox1.Size = New Size(240, 240)

    ' Populate the ListBox.ObjectCollection property 
    ' with several strings, using the AddRange method.
    Me.ListBox1.Items.AddRange(New Object() _
        {"System.Windows.Forms", "System.Drawing", "System.Xml", _
        "System.Net", "System.Runtime.Remoting", "System.Web"})

    ' Turn off the scrollbar.
    ListBox1.ScrollAlwaysVisible = False

    ' Set the border style to a single, flat border.
    ListBox1.BorderStyle = BorderStyle.FixedSingle

    ' Set the DrawMode property to the OwnerDrawVariable value. 
    ' This means the MeasureItem and DrawItem events must be 
    ' handled.
    ListBox1.DrawMode = DrawMode.OwnerDrawVariable
    Me.Controls.Add(Me.ListBox1)
End Sub


' Handle the DrawItem event for an owner-drawn ListBox.
Private Sub ListBox1_DrawItem(ByVal sender As Object, _
    ByVal e As DrawItemEventArgs) Handles ListBox1.DrawItem

    ' If the item is the selected item, then draw the rectangle filled in
    ' blue. The item is selected when a bitwise And of the State property
    ' and the DrawItemState.Selected property is true. 
    If (e.State And DrawItemState.Selected = DrawItemState.Selected) Then
        e.Graphics.FillRectangle(Brushes.CornflowerBlue, e.Bounds)
    Else
        ' Otherwise, draw the rectangle filled in beige.
        e.Graphics.FillRectangle(Brushes.Beige, e.Bounds)
    End If

    ' Draw a rectangle in blue around each item.
    e.Graphics.DrawRectangle(Pens.Blue, e.Bounds)

    ' Draw the text in the item.
    e.Graphics.DrawString(Me.ListBox1.Items(e.Index), Me.Font, _
        Brushes.Black, e.Bounds.X, e.Bounds.Y)

    ' Draw the focus rectangle around the selected item.
    e.DrawFocusRectangle()
End Sub

' Handle the MeasureItem event for an owner-drawn ListBox.
Private Sub ListBox1_MeasureItem(ByVal sender As Object, _
    ByVal e As MeasureItemEventArgs) Handles ListBox1.MeasureItem

    ' Cast the sender object back to ListBox type.
    Dim theListBox As ListBox = CType(sender, ListBox)

    ' Get the string contained in each item.
    Dim itemString As String = CType(theListBox.Items(e.Index), String)

    ' Split the string at the " . "  character.
    Dim resultStrings() As String = itemString.Split(".")

    ' If the string contains more than one period, increase the 
    ' height by ten pixels; otherwise, increase the height by 
    ' five pixels.
    If (resultStrings.Length > 2) Then
        e.ItemHeight += 10
    Else
        e.ItemHeight += 5
    End If

End Sub

Uwagi

Jeśli Sorted Właściwość ListBox jest ustawiona na true , elementy są wstawiane do listy alfabetycznie.If the Sorted property of the ListBox is set to true, the items are inserted into the list alphabetically. W przeciwnym razie elementy są wstawiane w kolejności, w jakiej występują w tablicy.Otherwise, the items are inserted in the order that they occur within the array. Ta metoda jest zwykle przenoszona tablicą String obiektów, ale tablica dowolnego typu obiektu może być przenoszona do tej metody.This method is typically passed an array of String objects, but an array of any type of object can be passed to this method. Po dodaniu obiektu do kolekcji, ListBox najpierw sprawdza, czy DisplayMember Właściwość ListControl klasy ma nazwę elementu członkowskiego z obiektu określonego jako odwołanie podczas uzyskiwania tekstu elementu.When an object is added to the collection, the ListBox first checks to see if the DisplayMember property of the ListControl class has the name of a member from the object specified to reference when obtaining the item text. Jeśli DisplayMember Właściwość nie ma określonego elementu członkowskiego, ListBox ToString Metoda wywołuje metodę obiektu w celu uzyskania tekstu do wyświetlenia na liście.If the DisplayMember property does not have a member specified, the ListBox then calls the ToString method of the object to obtain the text to display in the list. W przypadku użycia tej metody do dodawania elementów do ListBox , nie trzeba wywoływać BeginUpdate metod i, EndUpdate Aby zoptymalizować wydajność.When using this method to add items to the ListBox, you do not need to call the BeginUpdate and EndUpdate methods to optimize performance. Podczas dodawania elementów do ListBox , bardziej wydajne jest sortowanie elementów, a następnie dodawanie nowych elementów.When adding items to a ListBox, it is more efficient to sort the items first and then add new items. Za pomocą tej metody można dodać grupę elementów do listy lub ponownie użyć elementów przechowywanych w innym ListBox .You can use this method to add a group of items to the list or to reuse the items stored in a different ListBox.

Zobacz też

Dotyczy

AddRange(ListBox+ObjectCollection)

Dodaje elementy istniejącej ListBox.ObjectCollection do listy elementów w ListBox .Adds the items of an existing ListBox.ObjectCollection to the list of items in a ListBox.

public:
 void AddRange(System::Windows::Forms::ListBox::ObjectCollection ^ value);
public void AddRange (System.Windows.Forms.ListBox.ObjectCollection value);
member this.AddRange : System.Windows.Forms.ListBox.ObjectCollection -> unit
Public Sub AddRange (value As ListBox.ObjectCollection)

Parametry

value
ListBox.ObjectCollection

A ListBox.ObjectCollection do załadowania do tej kolekcji.A ListBox.ObjectCollection to load into this collection.

Wyjątki

.NET 5,0 i nowsze: value is null ..NET 5.0 and later: value is null.

Uwagi

Jeśli Sorted Właściwość ListBox jest ustawiona na true , elementy są wstawiane do listy alfabetycznie.If the Sorted property of the ListBox is set to true, the items are inserted into the list alphabetically. W przeciwnym razie elementy są wstawiane w kolejności, w jakiej występują w tablicy.Otherwise, the items are inserted in the order that they occur within the array. Ta metoda jest zwykle przenoszona tablicą String obiektów, ale tablica dowolnego typu obiektu może być przenoszona do tej metody.This method is typically passed an array of String objects, but an array of any type of object can be passed to this method. Po dodaniu obiektu do kolekcji, ListBox najpierw sprawdza, czy DisplayMember Właściwość ListControl klasy ma nazwę elementu członkowskiego z obiektu określonego jako odwołanie podczas uzyskiwania tekstu elementu.When an object is added to the collection, the ListBox first checks to see if the DisplayMember property of the ListControl class has the name of a member from the object specified to reference when obtaining the item text. Jeśli DisplayMember Właściwość nie ma określonego elementu członkowskiego, ListBox ToString Metoda wywołuje metodę obiektu w celu uzyskania tekstu do wyświetlenia na liście.If the DisplayMember property does not have a member specified, the ListBox then calls the ToString method of the object to obtain the text to display in the list.

W przypadku użycia tej metody do dodawania elementów do ListBox , nie trzeba wywoływać BeginUpdate metod i, EndUpdate Aby zoptymalizować wydajność.When using this method to add items to the ListBox, you do not need to call the BeginUpdate and EndUpdate methods to optimize performance. Podczas dodawania elementów do ListBox , bardziej wydajne jest sortowanie elementów, a następnie dodawanie nowych elementów.When adding items to a ListBox, it is more efficient to sort the items first and then add new items. Za pomocą tej metody można ponownie użyć elementów przechowywanych w innym ListBox .You can use this method to reuse the items stored in a different ListBox.

Zobacz też

Dotyczy