ImageList Class

 

Provides methods to manage a collection of Image objects. This class cannot be inherited.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

System.Object
  System.MarshalByRefObject
    System.ComponentModel.Component
      System.Windows.Forms.ImageList

Public NotInheritable Class ImageList
	Inherits Component

NameDescription
System_CAPS_pubmethodImageList()

Initializes a new instance of the ImageList class with default values for ColorDepth, ImageSize, and TransparentColor.

System_CAPS_pubmethodImageList(IContainer)

Initializes a new instance of the ImageList class, associating it with a container.

NameDescription
System_CAPS_pubpropertyColorDepth

Gets the color depth of the image list.

System_CAPS_pubpropertyContainer

Gets the IContainer that contains the Component.(Inherited from Component.)

System_CAPS_pubpropertyHandle

Gets the handle of the image list object.

System_CAPS_pubpropertyHandleCreated

Gets a value indicating whether the underlying Win32 handle has been created.

System_CAPS_pubpropertyImages

Gets the ImageList.ImageCollection for this image list.

System_CAPS_pubpropertyImageSize

Gets or sets the size of the images in the image list.

System_CAPS_pubpropertyImageStream

Gets the ImageListStreamer associated with this image list.

System_CAPS_pubpropertySite

Gets or sets the ISite of the Component.(Inherited from Component.)

System_CAPS_pubpropertyTag

Gets or sets an object that contains additional data about the ImageList.

System_CAPS_pubpropertyTransparentColor

Gets or sets the color to treat as transparent.

NameDescription
System_CAPS_pubmethodCreateObjRef(Type)

Creates an object that contains all the relevant information required to generate a proxy used to communicate with a remote object.(Inherited from MarshalByRefObject.)

System_CAPS_pubmethodDispose()

Releases all resources used by the Component.(Inherited from Component.)

System_CAPS_pubmethodDraw(Graphics, Int32, Int32, Int32)

Draws the image indicated by the given index on the specified Graphics at the specified location.

System_CAPS_pubmethodDraw(Graphics, Int32, Int32, Int32, Int32, Int32)

Draws the image indicated by the given index on the specified Graphics using the specified location and size.

System_CAPS_pubmethodDraw(Graphics, Point, Int32)

Draws the image indicated by the specified index on the specified Graphics at the given location.

System_CAPS_pubmethodEquals(Object)

Determines whether the specified object is equal to the current object.(Inherited from Object.)

System_CAPS_pubmethodGetHashCode()

Serves as the default hash function. (Inherited from Object.)

System_CAPS_pubmethodGetLifetimeService()

Retrieves the current lifetime service object that controls the lifetime policy for this instance.(Inherited from MarshalByRefObject.)

System_CAPS_pubmethodGetType()

Gets the Type of the current instance.(Inherited from Object.)

System_CAPS_pubmethodInitializeLifetimeService()

Obtains a lifetime service object to control the lifetime policy for this instance.(Inherited from MarshalByRefObject.)

System_CAPS_pubmethodToString()

This API supports the product infrastructure and is not intended to be used directly from your code. Returns a string that represents the current ImageList.(Overrides Component.ToString().)

NameDescription
System_CAPS_pubeventDisposed

Occurs when the component is disposed by a call to the Dispose method. (Inherited from Component.)

System_CAPS_pubeventRecreateHandle

Occurs when the Handle is recreated.

ImageList is typically used by other controls, such as the ListView, TreeView, or ToolBar. You can add bitmaps or icons to the ImageList, and the other controls are able to use the images as they require.

ImageList uses a handle to manage the list of images. The Handle is not created until certain operations, such as getting the Handle or calling Draw, are performed on the image list. Performing other operations, such as setting the ColorDepth or ImageSize will cause the Handle to be recreated. Therefore, you should perform these operations before you add images to the ImageList. In addition, when you work with forms that will be localized, you should always add an ImageList and images when the Language property of a form is set to Default. Changing the form's language before you add images will corrupt the application resource files.

The following code example shows how to select, remove, and display images.

Imports System
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 'NewNew

    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

.NET Framework
Available since 1.1

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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