Leadtools.Windows.Controls Namespace > RasterImageBox Class : AutoDisposeImages Property |
public bool AutoDisposeImages {get; set;}
'Declaration Public Property AutoDisposeImages As Boolean
'Usage Dim instance As RasterImageBox Dim value As Boolean instance.AutoDisposeImages = value value = instance.AutoDisposeImages
public bool AutoDisposeImages {get; set;}
get_AutoDisposeImages();
set_AutoDisposeImages(value);
By default, whenever you set a new Leadtools.RasterImage object into the Image property, the old image (if any) is disposed. Set the value of this property to false to prevent disposing of the old image.
Public Sub RasterImageBox_AutoDisposeImages(ByVal imageBox As RasterImageBox) ' Load two image2 Dim codecs As New RasterCodecs() Dim file1 As String = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp") Dim file2 As String = Path.Combine(LEAD_VARS.ImagesDir, "Image2.cmp") Dim image1 As RasterImage = codecs.Load(file1) Dim image2 As RasterImage = codecs.Load(file2) ' Make sure the AutoDisposeImage property of the image box is set to true imageBox.AutoDisposeImages = True ' Set the first image into the image box imageBox.Image = image1 ' Now set the second image into the image box (this disposes the first image since the AutoDisposeImage property is true) imageBox.Image = image2 ' Try to access the first image, it generates a NullReferenceException exception since the image has been disposed MessageBox.Show("Try to access the first image, it generates a NullReferenceException exception since the image has been disposed.") Try Dim width As Integer = image1.Width MessageBox.Show(String.Format("Width is {0} pixels", width)) Catch ex As NullReferenceException MessageBox.Show(ex.Message) End Try ' Set the image to Nothing (will dispose the second image as well) imageBox.Image = Nothing ' Now re-load the two images image1 = codecs.Load(file1) image2 = codecs.Load(file2) ' Make sure the AutoDisposeImage property of the image box is set to false imageBox.AutoDisposeImages = False ' Set the first image into the image box imageBox.Image = image1 ' Now set the second image into the image box (this will not disposes the first image since the AutoDisposeImage property is false) imageBox.Image = image2 ' Try to access the first image, it should work fine this time Try Dim width As Integer = image1.Width MessageBox.Show(String.Format("Width is {0} pixels", width)) Catch ex As NullReferenceException MessageBox.Show(ex.Message) End Try ' Set the image to Nothing (will not dispose the second image) imageBox.Image = Nothing ' We should now dispose the two images manually image1.Dispose() image2.Dispose() codecs.Dispose() End Sub Public NotInheritable Class LEAD_VARS Public Const ImagesDir As String = "C:\Users\Public\Documents\LEADTOOLS Images" End Class
public void RasterImageBox_AutoDisposeImages(RasterImageBox imageBox) { // Load two image2 RasterCodecs codecs = new RasterCodecs(); string file1 = Path.Combine(LEAD_VARS.ImagesDir, "Image1.cmp"); string file2 = Path.Combine(LEAD_VARS.ImagesDir, "Image2.cmp"); RasterImage image1 = codecs.Load(file1); RasterImage image2 = codecs.Load(file2); // Make sure the AutoDisposeImage property of the image box is set to true imageBox.AutoDisposeImages = true; // Set the first image into the image box imageBox.Image = image1; // Now set the second image into the image box (this disposes the first image since the AutoDisposeImage property is true) imageBox.Image = image2; // Try to access the first image, it generates a NullReferenceException exception since the image has been disposed MessageBox.Show("Try to access the first image, it generates a NullReferenceException exception since the image has been disposed."); try { int width = image1.Width; MessageBox.Show(string.Format("Width is {0} pixels", width)); } catch(NullReferenceException ex) { MessageBox.Show(ex.Message); } // Set the image to null (will dispose the second image as well) imageBox.Image = null; // Now re-load the two images image1 = codecs.Load(file1); image2 = codecs.Load(file2); // Make sure the AutoDisposeImage property of the image box is set to false imageBox.AutoDisposeImages = false; // Set the first image into the image box imageBox.Image = image1; // Now set the second image into the image box (this will not disposes the first image since the AutoDisposeImage property is false) imageBox.Image = image2; // Try to access the first image, it should work fine this time try { int width = image1.Width; MessageBox.Show(string.Format("Width is {0} pixels", width)); } catch(NullReferenceException ex) { MessageBox.Show(ex.Message); } // Set the image to null (will not dispose the second image) imageBox.Image = null; // We should now dispose the two images manually image1.Dispose(); image2.Dispose(); codecs.Dispose(); } static class LEAD_VARS { public const string ImagesDir = @"C:\Users\Public\Documents\LEADTOOLS Images"; }
Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2