Classe Image (System.Drawing)

Cambia visualizzazione:
ScriptFree
Riferimento a .NET Framework
Classe Image

Classe di base astratta che fornisce funzionalità per le classi derivate Bitmap e Metafile.

Spazio dei nomi: System.Drawing
Assembly: System.Drawing (in system.drawing.dll)

Sintassi

Visual Basic - (Dichiarazione)
<SerializableAttribute> _
<ComVisibleAttribute(True)> _
Public MustInherit Class Image
	Inherits MarshalByRefObject
	Implements ISerializable, ICloneable, IDisposable
Visual Basic (Utilizzo)
Dim instance As Image

C#
[SerializableAttribute] 
[ComVisibleAttribute(true)] 
public abstract class Image : MarshalByRefObject, ISerializable, ICloneable, IDisposable
C++
[SerializableAttribute] 
[ComVisibleAttribute(true)] 
public ref class Image abstract : public MarshalByRefObject, ISerializable, ICloneable, IDisposable
J#
/** @attribute SerializableAttribute() */ 
/** @attribute ComVisibleAttribute(true) */ 
public abstract class Image extends MarshalByRefObject implements ISerializable, ICloneable, 
	IDisposable
JScript
SerializableAttribute 
ComVisibleAttribute(true) 
public abstract class Image extends MarshalByRefObject implements ISerializable, ICloneable, 
	IDisposable
Esempio

Nell'esempio di codice riportato di seguito viene illustrato come costruire un nuovo oggetto Bitmap da un file, utilizzando i metodi GetPixel e SetPixel per ricolorare l'immagine. Vengono inoltre utilizzate le proprietà PixelFormat, Width e Height.

Questo esempio è progettato per l'uso con un Windows Form contenente oggetti Label, PictureBox e Button denominati rispettivamente Label1PictureBox1 e Button1. Incollare il codice nel form e associare il metodo Button1_Click all'evento Click del pulsante.

Visual Basic
Dim image1 As Bitmap

Private Sub Button1_Click(ByVal sender As System.Object, _
    ByVal e As System.EventArgs) Handles Button1.Click

    Try
        ' Retrieve the image.
        image1 = New Bitmap( _
            "C:\Documents and Settings\All Users\Documents\My Music\music.bmp", _
            True)

        Dim x, y As Integer

        ' Loop through the images pixels to reset color.
        For x = 0 To image1.Width - 1
            For y = 0 To image1.Height - 1
                Dim pixelColor As Color = image1.GetPixel(x, y)
                Dim newColor As Color = _
                    Color.FromArgb(pixelColor.R, 0, 0)
                image1.SetPixel(x, y, newColor)
            Next
        Next

        ' Set the PictureBox to display the image.
        PictureBox1.Image = image1

        ' Display the pixel format in Label1.
        Label1.Text = "Pixel format: " + image1.PixelFormat.ToString()

    Catch ex As ArgumentException
        MessageBox.Show("There was an error." _
            & "Check the path to the image file.")
    End Try
End Sub

C#
Bitmap image1;

private void Button1_Click(System.Object sender, System.EventArgs e)
{

    try
    {
        // Retrieve the image.
        image1 = new Bitmap(@"C:\Documents and Settings\All Users\" 
            + @"Documents\My Music\music.bmp", true);

        int x, y;

        // Loop through the images pixels to reset color.
        for(x=0; x<image1.Width; x++)
        {
            for(y=0; y<image1.Height; y++)
            {
                Color pixelColor = image1.GetPixel(x, y);
                Color newColor = Color.FromArgb(pixelColor.R, 0, 0);
                image1.SetPixel(x, y, newColor);
            }
        }

        // Set the PictureBox to display the image.
        PictureBox1.Image = image1;

        // Display the pixel format in Label1.
        Label1.Text = "Pixel format: "+image1.PixelFormat.ToString();

    }
    catch(ArgumentException)
    {
        MessageBox.Show("There was an error." +
            "Check the path to the image file.");
    }
}

C++
private:
   Bitmap^ image1;
   void Button1_Click( System::Object^ /*sender*/, System::EventArgs^ /*e*/ )
   {
      try
      {
         
         // Retrieve the image.
         image1 = gcnew Bitmap( "C:\\Documents and Settings\\All Users\\"
         "Documents\\My Music\\music.bmp",true );
         int x;
         int y;
         
         // Loop through the images pixels to reset color.
         for ( x = 0; x < image1->Width; x++ )
         {
            for ( y = 0; y < image1->Height; y++ )
            {
               Color pixelColor = image1->GetPixel( x, y );
               Color newColor = Color::FromArgb( pixelColor.R, 0, 0 );
               image1->SetPixel( x, y, newColor );

            }

         }
         
         // Set the PictureBox to display the image.
         PictureBox1->Image = image1;
         
         // Display the pixel format in Label1.
         Label1->Text = String::Format( "Pixel format: {0}", image1->PixelFormat );
      }
      catch ( ArgumentException^ ) 
      {
         MessageBox::Show( "There was an error."
         "Check the path to the image file." );
      }

   }

J#
private Bitmap image1;

private void button1_Click(Object sender, System.EventArgs e)
{
    try {
        // Retrieve the image.
        image1 = new Bitmap("C:\\Documents and Settings\\All Users\\"  
            + "Documents\\My Music\\music.bmp", true);

        int x, y;

        // Loop through the images pixels to reset color.
        for (x = 0; x < image1.get_Width(); x++) {
            for (y = 0; y < image1.get_Height(); y++) {
                Color pixelColor = image1.GetPixel(x, y);
                Color newColor = Color.FromArgb(pixelColor.get_R(), 0, 0);

                image1.SetPixel(x, y, newColor);
            }
        }

        // Set the PictureBox to display the image.
        pictureBox1.set_Image(image1);

        // Display the pixel format in label1.
        label1.set_Text("Pixel format: " 
            + image1.get_PixelFormat().ToString());
    }
    catch (ArgumentException exp) {
        MessageBox.Show(("There was an error."  
            + "Check the path to the image file."));
    }
} //button1_Click

Gerarchia di ereditarietà

System.Object
   System.MarshalByRefObject
    System.Drawing.Image
       System.Drawing.Bitmap
       System.Drawing.Imaging.Metafile
Codice thread safe

I membri statici pubblici (Shared in Visual Basic) di questo tipo sono validi per le operazioni multithreading. I membri di istanza non sono garantiti come thread safe.
Piattaforme

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

.NET Framework non supporta tutte le versioni di ciascuna piattaforma. Per un elenco delle versioni supportate, vedere Requisiti di sistema.

Informazioni sulla versione

.NET Framework

Supportato in: 2.0 1.1 1.0

.NET Compact Framework

Supportato in: 2.0 1.0
Vedere anche