ImageList Classe

Definizione

Spazio dei nomi:

System.Windows.Forms

Assembly:

System.Windows.Forms.dll

Fornisce i metodi per la gestione di un insieme di oggetti Image. La classe non può essere ereditata.

public ref class ImageList sealed : System::ComponentModel::Component

[System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.ImageListConverter))]
public sealed class ImageList : System.ComponentModel.Component

[<System.ComponentModel.TypeConverter(typeof(System.Windows.Forms.ImageListConverter))>]
type ImageList = class
    inherit Component

Public NotInheritable Class ImageList
Inherits Component

Ereditarietà

Object

MarshalByRefObject

Component

ImageList

Attributi

TypeConverterAttribute

Esempio

Nell'esempio di codice seguente viene illustrato come selezionare, rimuovere e visualizzare immagini.

namespace myImageRotator
#using <System.dll>
#using <System.Drawing.dll>
#using <System.Windows.Forms.dll>
{
    using namespace System;
    using namespace System::Drawing;
    using namespace System::ComponentModel;
    using namespace System::Windows::Forms;

    public ref class Form1 : public System::Windows::Forms::Form
    {
    private:
        System::ComponentModel::IContainer^ components;
    private:
        System::Windows::Forms::ListBox^ listBox1;
    private:
        System::Windows::Forms::Label^ label3;
    private:
        System::Windows::Forms::Button^ button1;
    private:
        System::Windows::Forms::Button^ button2;
    private:
        System::Windows::Forms::Button^ button3;
    private:
        System::Windows::Forms::Button^ button4;
    private:
        System::Windows::Forms::PictureBox^ pictureBox1;
    private:
        System::Windows::Forms::ImageList^ imageList1;
    private:
        System::Windows::Forms::OpenFileDialog^ openFileDialog1;
    protected:
        Graphics^ myGraphics;
    private:
        System::Windows::Forms::Panel^ panel1;
    private:
        System::Windows::Forms::Label^ label5;
    private:
        int currentImage;

    public:
        Form1()
        {
            InitializeComponent();
            imageList1 = gcnew ImageList () ;
            currentImage = 0;

            // The default image size is 16 x 16, which sets up a larger
            // image size. 
            imageList1->ImageSize = System::Drawing::Size(255,255);
            imageList1->TransparentColor = Color::White;

            // Assigns the graphics object to use in the draw options.
            myGraphics = Graphics::FromHwnd(panel1->Handle);
        }

    private:
        void InitializeComponent()
        {
            this->components = gcnew System::ComponentModel::Container();
            this->listBox1 = gcnew System::Windows::Forms::ListBox();
            this->label3 = gcnew System::Windows::Forms::Label();
            this->button1 = gcnew System::Windows::Forms::Button();
            this->button2 = gcnew System::Windows::Forms::Button();
            this->button3 = gcnew System::Windows::Forms::Button();
            this->button4 = gcnew System::Windows::Forms::Button();
            this->pictureBox1 = gcnew System::Windows::Forms::PictureBox();
            this->imageList1 = gcnew System::Windows::Forms::ImageList(this->components);
            this->openFileDialog1 = gcnew System::Windows::Forms::OpenFileDialog();
            this->panel1 = gcnew System::Windows::Forms::Panel();
            this->label5 = gcnew System::Windows::Forms::Label();
            this->SuspendLayout();

            this->listBox1->Location = System::Drawing::Point(16, 16);
            this->listBox1->Size = System::Drawing::Size(400, 95);
            this->listBox1->TabIndex = 0;

            this->label3->Location = System::Drawing::Point(24, 168);
            this->label3->Text = "label3";

            this->button1->Location = System::Drawing::Point(96, 128);
            this->button1->Size = System::Drawing::Size(104, 23);
            this->button1->Text = "Show Next Image";
            this->button1->Click += gcnew System::EventHandler(this,&Form1::button1_Click);

            this->button2->Location = System::Drawing::Point(208, 128);
            this->button2->Size = System::Drawing::Size(104, 23);
            this->button2->Text = "Remove Image";
            this->button2->Click += gcnew System::EventHandler(this,&Form1::button2_Click);

            this->button3->Location = System::Drawing::Point(320, 128);
            this->button3->Text = "Clear List";
            this->button3->Click += gcnew System::EventHandler(this,&Form1::button3_Click);

            this->button4->Location = System::Drawing::Point(16, 128);
            this->button4->Text = "Open Image";
            this->button4->Click += gcnew System::EventHandler(this,&Form1::button4_Click);

            this->pictureBox1->Location = System::Drawing::Point(328, 232);
            this->pictureBox1->Size = System::Drawing::Size(336, 192);

            this->imageList1->ImageSize = System::Drawing::Size(16, 16);
            this->imageList1->TransparentColor = System::Drawing::Color::Transparent;

            this->panel1->Location = System::Drawing::Point(8, 240);
            this->panel1->Size = System::Drawing::Size(296, 184);

            this->label5->Location = System::Drawing::Point(168, 168);
            this->label5->Size = System::Drawing::Size(312, 40);
            this->label5->Text = "label5";

            this->ClientSize = System::Drawing::Size(672, 461);
            this->Controls->Add(this->label5);
            this->Controls->Add(this->panel1);
            this->Controls->Add(this->pictureBox1);
            this->Controls->Add(this->button4);
            this->Controls->Add(this->button3);
            this->Controls->Add(this->button2);
            this->Controls->Add(this->button1);
            this->Controls->Add(this->label3);
            this->Controls->Add(this->listBox1);
            this->ResumeLayout(false);
        }

        // Display the image.
    private:
        void button1_Click (Object^ /*sender*/, System::EventArgs^ /*e*/)
        {
            if(imageList1->Images->Empty != true)
            {
                if(imageList1->Images->Count-1 > currentImage)
                {
                    currentImage++;
                }
                else
                {
                    currentImage=0;
                }
                panel1->Refresh();

                // Draw the image in the panel.
                imageList1->Draw(myGraphics,10,10,currentImage);

                // Show the image in the PictureBox.
                pictureBox1->Image = imageList1->Images[currentImage];
                label3->Text = "Current image is " + currentImage ;
                listBox1->SelectedIndex = currentImage;
                //				label5->Text = "Image is " + listBox1->Text ;
                label5->Text = String::Concat("Image is ",listBox1->Text);
            }
        }

        // Remove the image.
    private:
        void button2_Click (Object^ /*sender*/, System::EventArgs^ /*e*/)
        {
            imageList1->Images->RemoveAt(listBox1->SelectedIndex);
            listBox1->Items->Remove(listBox1->SelectedItem);
        }

        // Clear all images.
    private:
        void button3_Click (Object^ /*sender*/, System::EventArgs^ /*e*/)
        {
            imageList1->Images->Clear();
            listBox1->Items->Clear();
        }

        // Find an image.
    private:
        void button4_Click (Object^ /*sender*/, System::EventArgs^ /*e*/)
        {
            openFileDialog1->Multiselect = true ;
            if(openFileDialog1->ShowDialog() == System::Windows::Forms::DialogResult::OK)
            {
                if (openFileDialog1->FileNames != nullptr)
                {
                    for(int i =0 ; i < openFileDialog1->FileNames->Length ; i++ )
                    {
                        addImage(openFileDialog1->FileNames[i]);
                    }
                }
                else
                    addImage(openFileDialog1->FileName);
            }
           
        }

    private:
        void addImage(String^ imageToLoad)
        {
            if (imageToLoad != "")
            {
                imageList1->Images->Add(Image::FromFile(imageToLoad));
                listBox1->BeginUpdate();
                listBox1->Items->Add(imageToLoad);
                listBox1->EndUpdate();
            }
        }

    public:
        static void Main(array<String^>^ /*args*/) 
        {
            Application::Run(gcnew Form1());
        }
    };

}
[STAThreadAttribute] 
int main(){
    myImageRotator::Form1::Main(nullptr);
}

namespace myImageRotator
{
    using System;
    using System.Drawing;
    using System.ComponentModel;
    using System.Windows.Forms;
 
    public class Form1 : System.Windows.Forms.Form
    {
        private System.ComponentModel.IContainer components;
        private System.Windows.Forms.ListBox listBox1;
        private System.Windows.Forms.Label label3;
        private System.Windows.Forms.Button button1;
        private System.Windows.Forms.Button button2;
        private System.Windows.Forms.Button button3;
        private System.Windows.Forms.Button button4;
        private System.Windows.Forms.PictureBox pictureBox1;
        private System.Windows.Forms.ImageList imageList1;
        private System.Windows.Forms.OpenFileDialog openFileDialog1;
        protected Graphics myGraphics;
        private System.Windows.Forms.Panel panel1;
        private System.Windows.Forms.Label label5;
        private int currentImage = 0;
 
        public Form1()
        {
            InitializeComponent();
            imageList1 = new ImageList () ;

            // The default image size is 16 x 16, which sets up a larger
            // image size. 
            imageList1.ImageSize = new Size(255,255);
            imageList1.TransparentColor = Color.White;

            // Assigns the graphics object to use in the draw options.
            myGraphics = Graphics.FromHwnd(panel1.Handle);
        }
 
        private void InitializeComponent()
        {
            this.components = new System.ComponentModel.Container();
            this.listBox1 = new System.Windows.Forms.ListBox();
            this.label3 = new System.Windows.Forms.Label();
            this.button1 = new System.Windows.Forms.Button();
            this.button2 = new System.Windows.Forms.Button();
            this.button3 = new System.Windows.Forms.Button();
            this.button4 = new System.Windows.Forms.Button();
            this.pictureBox1 = new System.Windows.Forms.PictureBox();
            this.imageList1 = new System.Windows.Forms.ImageList(this.components);
            this.openFileDialog1 = new System.Windows.Forms.OpenFileDialog();
            this.panel1 = new System.Windows.Forms.Panel();
            this.label5 = new System.Windows.Forms.Label();
            this.SuspendLayout();

            this.listBox1.Location = new System.Drawing.Point(16, 16);
            this.listBox1.Size = new System.Drawing.Size(400, 95);
            this.listBox1.TabIndex = 0;

            this.label3.Location = new System.Drawing.Point(24, 168);
            this.label3.Text = "label3";

            this.button1.Location = new System.Drawing.Point(96, 128);
            this.button1.Size = new System.Drawing.Size(104, 23);
            this.button1.Text = "Show Next Image";
            this.button1.Click += new System.EventHandler(this.button1_Click);

            this.button2.Location = new System.Drawing.Point(208, 128);
            this.button2.Size = new System.Drawing.Size(104, 23);
            this.button2.Text = "Remove Image";
            this.button2.Click += new System.EventHandler(this.button2_Click);

            this.button3.Location = new System.Drawing.Point(320, 128);
            this.button3.Text = "Clear List";
            this.button3.Click += new System.EventHandler(this.button3_Click);

            this.button4.Location = new System.Drawing.Point(16, 128);
            this.button4.Text = "Open Image";
            this.button4.Click += new System.EventHandler(this.button4_Click);

            this.pictureBox1.Location = new System.Drawing.Point(328, 232);
            this.pictureBox1.Size = new System.Drawing.Size(336, 192);

            this.imageList1.ImageSize = new System.Drawing.Size(16, 16);
            this.imageList1.TransparentColor = System.Drawing.Color.Transparent;

            this.panel1.Location = new System.Drawing.Point(8, 240);
            this.panel1.Size = new System.Drawing.Size(296, 184);

            this.label5.Location = new System.Drawing.Point(168, 168);
            this.label5.Size = new System.Drawing.Size(312, 40);
            this.label5.Text = "label5";

            this.ClientSize = new System.Drawing.Size(672, 461);
            this.Controls.Add(this.label5);
            this.Controls.Add(this.panel1);
            this.Controls.Add(this.pictureBox1);
            this.Controls.Add(this.button4);
            this.Controls.Add(this.button3);
            this.Controls.Add(this.button2);
            this.Controls.Add(this.button1);
            this.Controls.Add(this.label3);
            this.Controls.Add(this.listBox1);
            this.ResumeLayout(false);
        }

        // Display the image.
        private void button1_Click (object sender, System.EventArgs e)
        {
            if(imageList1.Images.Empty != true)
            {
                if(imageList1.Images.Count-1 > currentImage)
                {
                    currentImage++;
                }
                else
                {
                    currentImage=0;
                }
                panel1.Refresh();
                
                // Draw the image in the panel.
                imageList1.Draw(myGraphics,10,10,currentImage);

                // Show the image in the PictureBox.
                pictureBox1.Image = imageList1.Images[currentImage];
                label3.Text = "Current image is " + currentImage ;
                listBox1.SelectedIndex = currentImage;
                label5.Text = "Image is " + listBox1.Text ;
            }
        }
 
        // Remove the image.
        private void button2_Click (object sender, System.EventArgs e)
        {
            imageList1.Images.RemoveAt(listBox1.SelectedIndex);
            listBox1.Items.Remove(listBox1.SelectedItem);
        }
 
        // Clear all images.
        private void button3_Click (object sender, System.EventArgs e)
        {
            imageList1.Images.Clear();
            listBox1.Items.Clear();
        }
 
        // Find an image.
        private void button4_Click (object sender, System.EventArgs e)
        {
            openFileDialog1.Multiselect = true ;
            if(openFileDialog1.ShowDialog() == DialogResult.OK)
            {
                if (openFileDialog1.FileNames != null)
                {
                    for(int i =0 ; i < openFileDialog1.FileNames.Length ; i++ )
                    {
                        addImage(openFileDialog1.FileNames[i]);
                    }
                }
                else
                {
                    addImage(openFileDialog1.FileName);
                }
            }
        }
 
        private void addImage(string imageToLoad)
        {
            if (imageToLoad != "")
            {
                imageList1.Images.Add(Image.FromFile(imageToLoad));
                listBox1.BeginUpdate();
                listBox1.Items.Add(imageToLoad);
                listBox1.EndUpdate();
            }
        }
        [STAThread]
        public static void Main(string[] args) 
        {
            Application.Run(new Form1());
        }
    }
}

Imports System.Drawing
Imports System.ComponentModel
Imports System.Windows.Forms

Public Class Form1
    Inherits System.Windows.Forms.Form
    Private listBox1 As System.Windows.Forms.ListBox
    Private label3 As System.Windows.Forms.Label
    Private WithEvents button1 As System.Windows.Forms.Button
    Private WithEvents button2 As System.Windows.Forms.Button
    Private WithEvents button3 As System.Windows.Forms.Button
    Private WithEvents button4 As System.Windows.Forms.Button
    Private pictureBox1 As System.Windows.Forms.PictureBox
    Private imageList1 As System.Windows.Forms.ImageList
    Private openFileDialog1 As System.Windows.Forms.OpenFileDialog
    Protected myGraphics As Graphics
    Private panel1 As System.Windows.Forms.Panel
    Private label5 As System.Windows.Forms.Label
    Private currentImage As Integer = 0

    Public Sub New()
        imageList1 = New ImageList()

        InitializeComponent()
        ' The default image size is 16 x 16, which sets up a larger
        ' image size. 
        imageList1.ImageSize = New Size(255, 255)
        imageList1.TransparentColor = Color.White

        ' Assigns the graphics object to use in the draw options.
        myGraphics = Graphics.FromHwnd(panel1.Handle)

    End Sub

    Private Sub InitializeComponent()

        Me.listBox1 = New System.Windows.Forms.ListBox()
        Me.label3 = New System.Windows.Forms.Label()
        Me.button1 = New System.Windows.Forms.Button()
        Me.button2 = New System.Windows.Forms.Button()
        Me.button3 = New System.Windows.Forms.Button()
        Me.button4 = New System.Windows.Forms.Button()
        Me.pictureBox1 = New System.Windows.Forms.PictureBox()
        Me.openFileDialog1 = New System.Windows.Forms.OpenFileDialog()
        Me.panel1 = New System.Windows.Forms.Panel()
        Me.label5 = New System.Windows.Forms.Label()
        Me.SuspendLayout()

        Me.listBox1.Location = New System.Drawing.Point(16, 16)
        Me.listBox1.Size = New System.Drawing.Size(400, 95)
        Me.listBox1.TabIndex = 0

        Me.label3.Location = New System.Drawing.Point(24, 168)
        Me.label3.Text = "label3"

        Me.button1.Location = New System.Drawing.Point(96, 128)
        Me.button1.Size = New System.Drawing.Size(104, 23)
        Me.button1.Text = "Show Next Image"

        Me.button2.Location = New System.Drawing.Point(208, 128)
        Me.button2.Size = New System.Drawing.Size(104, 23)
        Me.button2.Text = "Remove Image"

        Me.button3.Location = New System.Drawing.Point(320, 128)
        Me.button3.Text = "Clear List"

        Me.button4.Location = New System.Drawing.Point(16, 128)
        Me.button4.Text = "Open Image"

        Me.pictureBox1.Location = New System.Drawing.Point(328, 232)
        Me.pictureBox1.Size = New System.Drawing.Size(336, 192)

        Me.imageList1.ImageSize = New System.Drawing.Size(16, 16)
        Me.imageList1.TransparentColor = System.Drawing.Color.Transparent

        Me.panel1.Location = New System.Drawing.Point(8, 240)
        Me.panel1.Size = New System.Drawing.Size(296, 184)

        Me.label5.Location = New System.Drawing.Point(168, 168)
        Me.label5.Size = New System.Drawing.Size(312, 40)
        Me.label5.Text = "label5"

        Me.ClientSize = New System.Drawing.Size(672, 461)
        Me.Controls.Add(label5)
        Me.Controls.Add(panel1)
        Me.Controls.Add(pictureBox1)
        Me.Controls.Add(button4)
        Me.Controls.Add(button3)
        Me.Controls.Add(button2)
        Me.Controls.Add(button1)
        Me.Controls.Add(label3)
        Me.Controls.Add(listBox1)
        Me.ResumeLayout(False)
    End Sub

    ' Display the image.
    Private Sub button1_Click(ByVal sender As Object, _
        ByVal e As System.EventArgs) Handles button1.Click

        If imageList1.Images.Empty <> True Then
            If imageList1.Images.Count - 1 > currentImage Then
                currentImage += 1
            Else
                currentImage = 0
            End If
            panel1.Refresh()

            ' Draw the image in the panel.
            imageList1.Draw(myGraphics, 10, 10, currentImage)

            ' Show the image in the PictureBox.
            pictureBox1.Image = imageList1.Images(currentImage)
            label3.Text = "Current image is " + currentImage.ToString
            listBox1.SelectedIndex = currentImage
            label5.Text = "Image is " + listBox1.Text
        End If
    End Sub

    ' Remove the image.
    Private Sub button2_Click(ByVal sender As Object, _
        ByVal e As System.EventArgs) Handles button2.Click

        imageList1.Images.RemoveAt(listBox1.SelectedIndex)
        listBox1.Items.Remove(listBox1.SelectedItem)
    End Sub

    ' Clear all images.
    Private Sub button3_Click(ByVal sender As Object, _
        ByVal e As System.EventArgs) Handles button3.Click
        imageList1.Images.Clear()
        listBox1.Items.Clear()
    End Sub

    ' Find an image.
    Private Sub button4_Click(ByVal sender As Object, _
        ByVal e As System.EventArgs) Handles button4.Click

        openFileDialog1.Multiselect = True
        If openFileDialog1.ShowDialog() = DialogResult.OK Then
            If (openFileDialog1.FileNames IsNot Nothing) Then
                Dim i As Integer
                For i = 0 To openFileDialog1.FileNames.Length - 1
                    addImage(openFileDialog1.FileNames(i))
                Next i
            Else
                addImage(openFileDialog1.FileName)
            End If
        End If
    End Sub

    Private Sub addImage(ByVal imageToLoad As String)
        If imageToLoad <> "" Then
            imageList1.Images.Add(Image.FromFile(imageToLoad))
            listBox1.BeginUpdate()
            listBox1.Items.Add(imageToLoad)
            listBox1.EndUpdate()
        End If
    End Sub

    <StaThread()> _
    Public Shared Sub Main(ByVal args() As String)
        Application.Run(New Form1())
    End Sub
End Class

Commenti

ImageListviene in genere usato da altri controlli, ad esempio , ListViewTreeViewo ToolBar. È possibile aggiungere bitmap o icone all'oggetto ImageListe gli altri controlli possono usare le immagini in base alle proprie richieste.

ImageList usa un handle per gestire l'elenco di immagini. L'oggetto Handle non viene creato fino a quando non vengono eseguite determinate operazioni, ad esempio ottenere o Handle chiamare Draw, nell'elenco di immagini. L'esecuzione di altre operazioni, ad esempio l'impostazione o ImageSize causerà la ricreazione dell'oggetto.ColorDepth Handle Pertanto, è necessario eseguire queste operazioni prima di aggiungere immagini all'oggetto ImageList. Inoltre, quando si utilizzano moduli che verranno localizzati, è consigliabile aggiungere sempre un oggetto ImageList e immagini quando la proprietà Language di un modulo è impostata su Default. Se si modifica la lingua del modulo prima di aggiungere immagini, i file di risorse dell'applicazione verranno danneggiati.

Costruttori

ImageList()	Inizializza una nuova istanza della classe ImageList con i valori predefiniti per ColorDepth, ImageSize e TransparentColor.
ImageList(IContainer)	Inizializza una nuova istanza della classe ImageList associandola a un contenitore.

Proprietà

CanRaiseEvents	Ottiene un valore che indica se il componente può generare un evento. (Ereditato da Component)
ColorDepth	Ottiene la profondità di colore dell'elenco immagini.
Container	Ottiene l'oggetto IContainer che contiene Component. (Ereditato da Component)
DesignMode	Ottiene un valore che indica se il Component si trova in modalità progettazione. (Ereditato da Component)
Events	Ottiene l'elenco dei gestori eventi allegati a questo Component. (Ereditato da Component)
Handle	Ottiene l'handle dell'oggetto elenco immagini.
HandleCreated	Ottiene un valore che indica se l'handle Win32 sottostante è stato creato.
Images	Ottiene l'oggetto ImageList.ImageCollection di questo elenco immagini.
ImageSize	Ottiene o imposta la dimensione delle immagini nell'elenco immagini.
ImageStream	Ottiene la classe ImageListStreamer associata a questo elenco immagini.
Site	Ottiene o imposta l'oggetto ISite di Component. (Ereditato da Component)
Tag	Ottiene o imposta un oggetto che contiene ulteriori dati relativi a ImageList.
TransparentColor	Ottiene o imposta il colore da considerare trasparente.

Metodi

CreateObjRef(Type)	Consente di creare un oggetto che contiene tutte le informazioni rilevanti necessarie per la generazione del proxy utilizzato per effettuare la comunicazione con un oggetto remoto. (Ereditato da MarshalByRefObject)
Dispose()	Rilascia tutte le risorse usate da Component. (Ereditato da Component)
Dispose(Boolean)	Rilascia le risorse non gestite usate da Component e, facoltativamente, le risorse gestite. (Ereditato da Component)
Draw(Graphics, Int32, Int32, Int32)	Disegna l'immagine indicata dall'indice dato sul Graphics specificato nella posizione specificata.
Draw(Graphics, Int32, Int32, Int32, Int32, Int32)	Disegna l'immagine indicata dall'indice dato sull'oggetto Graphics specificato utilizzando la posizione e le dimensioni specificate.
Draw(Graphics, Point, Int32)	Disegna l'immagine indicata dall'indice specificato sull'oggetto Graphics e nella posizione specificati.
Equals(Object)	Determina se l'oggetto specificato è uguale all'oggetto corrente. (Ereditato da Object)
GetHashCode()	Funge da funzione hash predefinita. (Ereditato da Object)
GetLifetimeService()	Obsoleta. Consente di recuperare l'oggetto servizio di durata corrente per controllare i criteri di durata per l'istanza. (Ereditato da MarshalByRefObject)
GetService(Type)	Consente di restituire un oggetto che rappresenta un servizio fornito da Component o dal relativo Container. (Ereditato da Component)
GetType()	Ottiene l'oggetto Type dell'istanza corrente. (Ereditato da Object)
InitializeLifetimeService()	Obsoleta. Ottiene un oggetto servizio di durata per controllare i criteri di durata per questa istanza. (Ereditato da MarshalByRefObject)
MemberwiseClone()	Crea una copia superficiale dell'oggetto Object corrente. (Ereditato da Object)
MemberwiseClone(Boolean)	Crea una copia dei riferimenti dell'oggetto MarshalByRefObject corrente. (Ereditato da MarshalByRefObject)
ToString()	Restituisce una stringa che rappresenta l'oggetto ImageList corrente.

Eventi

Disposed	Si verifica quando il componente viene eliminato da una chiamata al metodo Dispose(). (Ereditato da Component)
RecreateHandle	Si verifica quando viene ricreata la proprietà Handle.

Vedi anche

• Bitmap
• Icon
• Metafile