PictureBox PictureBox PictureBox Constructor

Definizione

Inizializza una nuova istanza della classe PictureBox.Initializes a new instance of the PictureBox class.

public:
 PictureBox();
public PictureBox ();
Public Sub New ()

Esempi

Nell'esempio di codice riportato di seguito viene illustrato PictureBox l' ListView utilizzo dei controlli e.The following code example demonstrates the use of the PictureBox and ListView controls. L' PictureBox oggetto viene inizializzato impostando SizeMode rispettivamente le BorderStyle proprietà BorderStyle e PictureBoxSizeMode usando le enumerazioni e.The PictureBox is initialized by setting the BorderStyle and SizeMode properties using the BorderStyle and PictureBoxSizeMode enumerations, respectively. ListView Viene popolato con le immagini dalla directory immagini di esempio.The ListView is populated with pictures from the Sample Pictures directory. Il ListView.GetItemAt metodo viene utilizzato quando si gestisce MouseDown l'evento del ListView controllo per determinare se un elemento è selezionato.The ListView.GetItemAt method is used when handling the MouseDown event of the ListView control to determine whether an item is selected. Se viene selezionato un elemento, il gestore eventi Visualizza il file selezionato impostando la Image proprietà.If an item is selected, the event handler displays the selected file by setting the Image property. Per l'esempio è necessario disporre di file JPG presenti nella directory C:\Documents and Settings\All all Immagini\immagini Pictures.The example requires that you have JPG files located in the C:\Documents and Settings\All Users\Documents\My Pictures\Sample Pictures directory. Per eseguire l'esempio, incollare il codice in un form e chiamare i InitializePictureBox metodi PopulateListView e nel costruttore del form o Load nel metodo di gestione degli eventi.To run the example, paste the code into a form and call the InitializePictureBox and PopulateListView methods in the form's constructor or Load event-handling method. Verificare che tutti gli eventi siano associati ai relativi metodi di gestione degli eventi.Ensure all events are associated with their event-handling methods.

private:
   void PopulateListView()
   {
      ListView1->Width = 270;
      ListView1->Location = System::Drawing::Point( 10, 10 );
      
      // Declare and construct the ColumnHeader objects.
      ColumnHeader^ header1;
      ColumnHeader^ header2;
      header1 = gcnew ColumnHeader;
      header2 = gcnew ColumnHeader;
      
      // Set the text, alignment and width for each column header.
      header1->Text = "File name";
      header1->TextAlign = HorizontalAlignment::Left;
      header1->Width = 70;
      header2->TextAlign = HorizontalAlignment::Left;
      header2->Text = "Location";
      header2->Width = 200;
      
      // Add the headers to the ListView control.
      ListView1->Columns->Add( header1 );
      ListView1->Columns->Add( header2 );
            
	  // Specify that each item appears on a separate line.
      ListView1->View = View::Details;

	  // Populate the ListView.Items property.
      // Set the directory to the sample picture directory.
      System::IO::DirectoryInfo^ dirInfo = gcnew System::IO::DirectoryInfo( "C:\\Documents and Settings\\All Users"
      "\\Documents\\My Pictures\\Sample Pictures" );
      
      // Get the .jpg files from the directory
      array<System::IO::FileInfo^>^files = dirInfo->GetFiles( "*.jpg" );
      
      // Add each file name and full name including path
      // to the ListView.
      if ( files != nullptr )
      {
         System::Collections::IEnumerator^ myEnum = files->GetEnumerator();
         while ( myEnum->MoveNext() )
         {
            System::IO::FileInfo^ file = safe_cast<System::IO::FileInfo^>(myEnum->Current);
            ListViewItem^ item = gcnew ListViewItem( file->Name );
            item->SubItems->Add( file->FullName );
            ListView1->Items->Add( item );
         }
      }
   }

   void InitializePictureBox()
   {
      PictureBox1 = gcnew PictureBox;
      
      // Set the location and size of the PictureBox control.
      this->PictureBox1->Location = System::Drawing::Point( 70, 120 );
      this->PictureBox1->Size = System::Drawing::Size( 140, 140 );
      this->PictureBox1->TabStop = false;
      
      // Set the SizeMode property to the StretchImage value.  This
      // will shrink or enlarge the image as needed to fit into
      // the PictureBox.
      this->PictureBox1->SizeMode = PictureBoxSizeMode::StretchImage;
      
      // Set the border style to a three-dimensional border.
      this->PictureBox1->BorderStyle = BorderStyle::Fixed3D;
      
      // Add the PictureBox to the form.
      this->Controls->Add( this->PictureBox1 );
   }

   void ListView1_MouseDown( Object^ /*sender*/, MouseEventArgs^ e )
   {
      ListViewItem^ selection = ListView1->GetItemAt( e->X, e->Y );
      
      // If the user selects an item in the ListView, display
      // the image in the PictureBox.
      if ( selection != nullptr )
      {
         PictureBox1->Image = System::Drawing::Image::FromFile( selection->SubItems[ 1 ]->Text );
      }
   }
private void PopulateListView()
{
	ListView1.Width = 270;
	ListView1.Location = new System.Drawing.Point(10, 10);

	// Declare and construct the ColumnHeader objects.
	ColumnHeader header1, header2;
	header1 = new ColumnHeader();
	header2 = new ColumnHeader();

	// Set the text, alignment and width for each column header.
	header1.Text = "File name";
	header1.TextAlign = HorizontalAlignment.Left;
	header1.Width = 70;

	header2.TextAlign = HorizontalAlignment.Left;
	header2.Text = "Location";
	header2.Width = 200;

	// Add the headers to the ListView control.
	ListView1.Columns.Add(header1);
	ListView1.Columns.Add(header2);

       // Specify that each item appears on a separate line.
       ListView1.View = View.Details;
       
       // Populate the ListView.Items property.
	// Set the directory to the sample picture directory.
	System.IO.DirectoryInfo dirInfo = 
		new System.IO.DirectoryInfo(
		"C:\\Documents and Settings\\All Users" +
		"\\Documents\\My Pictures\\Sample Pictures");
	

	// Get the .jpg files from the directory
	System.IO.FileInfo[] files = dirInfo.GetFiles("*.jpg");

	// Add each file name and full name including path
	// to the ListView.
	if (files != null)
	{
		foreach ( System.IO.FileInfo file in files )
		{
			ListViewItem item = new ListViewItem(file.Name);
			item.SubItems.Add(file.FullName);
			ListView1.Items.Add(item);
		}
	}
}

private void InitializePictureBox()
{
	PictureBox1 = new PictureBox();

	// Set the location and size of the PictureBox control.
	this.PictureBox1.Location = new System.Drawing.Point(70, 120);
	this.PictureBox1.Size = new System.Drawing.Size(140, 140);
	this.PictureBox1.TabStop = false;

	// Set the SizeMode property to the StretchImage value.  This
	// will shrink or enlarge the image as needed to fit into
	// the PictureBox.
	this.PictureBox1.SizeMode = PictureBoxSizeMode.StretchImage;

	// Set the border style to a three-dimensional border.
	this.PictureBox1.BorderStyle = BorderStyle.Fixed3D;

	// Add the PictureBox to the form.
	this.Controls.Add(this.PictureBox1);

}


private void ListView1_MouseDown(object sender, MouseEventArgs e)
{

	ListViewItem selection = ListView1.GetItemAt(e.X, e.Y);

	// If the user selects an item in the ListView, display
	// the image in the PictureBox.
	if (selection != null)
	{
		PictureBox1.Image = System.Drawing.Image.FromFile(
			selection.SubItems[1].Text);
	}
}
Private Sub PopulateListView()
    ListView1.Width = 270
    ListView1.Location = New System.Drawing.Point(10, 10)

    ' Declare and construct the ColumnHeader objects.
    Dim header1, header2 As ColumnHeader
    header1 = New ColumnHeader
    header2 = New ColumnHeader

    ' Set the text, alignment and width for each column header.
    header1.Text = "File name"
    header1.TextAlign = HorizontalAlignment.Left
    header1.Width = 70

    header2.TextAlign = HorizontalAlignment.Left
    header2.Text = "Location"
    header2.Width = 200

    ' Add the headers to the ListView control.
    ListView1.Columns.Add(header1)
    ListView1.Columns.Add(header2)

    ' Specify that each item appears on a separate line.
    ListView1.View = View.Details

    ' Populate the ListView.Items property.
    ' Set the directory to the sample picture directory.
    Dim dirInfo As New System.IO.DirectoryInfo _
        ("C:\Documents and Settings\All Users" _
        & "\Documents\My Pictures\Sample Pictures")
    Dim file As System.IO.FileInfo

    ' Get the .jpg files from the directory
    Dim files() As System.io.FileInfo = dirInfo.GetFiles("*.jpg")

    ' Add each file name and full name including path
    ' to the ListView.
    If (files IsNot Nothing) Then
        For Each file In files
            Dim item As New ListViewItem(file.Name)
            item.SubItems.Add(file.FullName)
            ListView1.Items.Add(item)
        Next
    End If
End Sub

Private Sub InitializePictureBox()
    PictureBox1 = New PictureBox

    ' Set the location and size of the PictureBox control.
    Me.PictureBox1.Location = New System.Drawing.Point(70, 120)
    Me.PictureBox1.Size = New System.Drawing.Size(140, 140)
    Me.PictureBox1.TabStop = False

    ' Set the SizeMode property to the StretchImage value.  This
    ' will shrink or enlarge the image as needed to fit into
    ' the PictureBox.
    Me.PictureBox1.SizeMode = PictureBoxSizeMode.StretchImage

    ' Set the border style to a three-dimensional border.
    Me.PictureBox1.BorderStyle = BorderStyle.Fixed3D

    ' Add the PictureBox to the form.
    Me.Controls.Add(Me.PictureBox1)

End Sub


Private Sub ListView1_MouseDown(ByVal sender As Object, _
    ByVal e As MouseEventArgs) Handles ListView1.MouseDown

    Dim selection As ListViewItem = ListView1.GetItemAt(e.X, e.Y)

    ' If the user selects an item in the ListView, display
    ' the image in the PictureBox.
    If (selection IsNot Nothing) Then
        PictureBox1.Image = System.Drawing.Image.FromFile _
            (selection.SubItems(1).Text)
    End If


End Sub

Commenti

Di seguito sono illustrati i valori iniziali delle proprietà di un'istanza della classe PictureBox.The following table shows initial property values for an instance of the PictureBox class.

ElementoItem DescriptionDescription
Image null
SizeMode Normal

Si applica a

Vedi anche