Develop Reference

Delete an image being used by another process

I am writing a winform application in C# to open an image and overlay another image on top of it.
The bottom image is a .jpg and the top one is a .bmp converted from .svg. The .jpg and the .svg are the only ones I want to keep in the folder. The .bmp works as a temp.
I was using the following code to overlay the images. But I am having trouble to delete the temp .bmp as it is used by another process. I think it is this combine code still have access to the last .bmp file.
Could anyone help me on this? Thanks.
private void buttonSearch_Click(object sender, EventArgs e)
{
FailInfo.Text = "";
deletebmp(strFolderPath);
...
// Check if the specified front image exists. Yes, show the file name and convert SVG to BMP. No, show the error msg.
if (File.Exists(strFilePathF))
{
labelFront.Text = strFileNameF;
var svgConvert = SvgDocument.Open(svgFilePathF);
svgConvert.Draw().Save(bmpFilePathF);
pictureBoxFront.Image = Image.FromFile(strFilePathF);
}
else
{
labelFront.Text = "Couldn't find the file!";
pictureBoxFront.Image = null;
}
// Check if the specified back image exists. Yes, show the file name and convert SVG to BMP. No, show the error msg.
if (File.Exists(strFilePathBF))
{
labelBack.Text = strFileNameBF;
strFilePathB = strFilePathBF;
pictureBoxBack.Image = Image.FromFile(strFilePathB);
labelResult.Text = "FAIL";
labelResult.BackColor = Color.FromArgb(255, 0, 0);
var svgConvert = SvgDocument.Open(svgFilePathBF);
bmpFilePathB = strFolderPath + strFileNameBF + ".bmp";
svgConvert.Draw().Save(bmpFilePathB);
svgFilePathB = svgFilePathBF;
inspectionres(svgFilePathB);
labelreason.Visible = true;
}
else if (File.Exists(strFilePathBP))
{
labelBack.Text = strFileNameBP;
strFilePathB = strFilePathBP;
pictureBoxBack.Image = Image.FromFile(strFilePathB);
labelResult.Text = "PASS";
labelResult.BackColor = Color.FromArgb(0, 255, 0);
var svgConvert = SvgDocument.Open(svgFilePathBP);
bmpFilePathB = strFolderPath + strFileNameBP + ".bmp";
svgConvert.Draw().Save(bmpFilePathB);
svgFilePathB = svgFilePathBP;
inspectionres(svgFilePathB);
labelreason.Visible = false;
}
else
{
labelBack.Text = "Couldn't find the file!";
pictureBoxBack.Image = null;
labelResult.Text = "ERROR";
labelResult.BackColor = Color.FromArgb(0, 255, 255);
labelreason.Visible = false;
}
}
//
// Overlay the SVG file on top of the JPEG file
//
private Bitmap Combine(string jpegFile, string bmpFile)
{
Image image1 = Image.FromFile(jpegFile);
Image image2 = Image.FromFile(bmpFile);
Bitmap temp = new Bitmap(image1.Width, image1.Height);
using (Graphics g = Graphics.FromImage(temp))
{
g.DrawImageUnscaled(image1, 0, 0);
g.DrawImageUnscaled(image2, 0, 0);
}
return temp;
}
//
// Show the overlaid graphic in the picturebox
//
private void checkBoxOverlay_CheckedChanged(object sender, EventArgs e)
{
try
{
if (FindFront)
if (checkBoxOverlay.Checked)
pictureBoxFront.Image = Combine(strFilePathF, bmpFilePathF);
else
pictureBoxFront.Image = Image.FromFile(strFilePathF);
else
pictureBoxFront.Image = null;
if (FindBack)
if (checkBoxOverlay.Checked)
pictureBoxBack.Image = Combine(strFilePathB, bmpFilePathB);
else
pictureBoxBack.Image = Image.FromFile(strFilePathB);
else
pictureBoxBack.Image = null;
}
catch (Exception ex)
{
MessageBox.Show("Error loading image" + ex.Message);
}
}
//
// Option of changing the image folder
//
private void buttonPath_Click(object sender, EventArgs e)
{
FolderBrowserDialog FolderBrowserDialog1 = new FolderBrowserDialog();
if (FolderBrowserDialog1.ShowDialog() == DialogResult.OK)
{
strFolderPath = FolderBrowserDialog1.SelectedPath + "\\";
}
}
//
// Pull the inspection result info from the SVG file
//
private void inspectionres(string filename)
{
XDocument document = XDocument.Load(filename);
XElement svg_Element = document.Root;
string sb = null;
var faillist = (from svg_path in svg_Element.Descendants("{http://www.w3.org/2000/svg}text") select svg_path).ToList();
foreach (var item in faillist)
{
sb += item.ToString();
}
}
//
// Delete all the .bmp files generated from .svg files
//
private void deletebmp(string path)
{
// Unload the images from the picturebox if applicable
pictureBoxFront.Image = null;
pictureBoxBack.Image = null;
string[] files = Directory.GetFiles(path, "*.bmp");
for (int i = 0; i < files.Length; i ++ )
File.Delete(files[i]);
}
}

Image implements IDisposable, so simply setting the pictureBox.Image property to null will not release resources (in your case, the file). Your Combine method also leaves the images open. You have to call Dispose before attempting to delete the file:
Image image1 = Image.FromFile(path1);
File.Delete(path1); // error - file is locked
Image image2 = Image.FromFile(path2);
image2.Dispose();
File.Delete(path2); // works
An alternative approach (and I assume you're using WinForms here, in WPF it's a little different) would be to load the bitmap from the file manually (using FromStream). Then, you can close the stream immediately and delete the file:
Image image;
using (Stream stream = File.OpenRead(path))
{
image = System.Drawing.Image.FromStream(stream);
}
pictureBox.Image = image;
File.Delete("e:\\temp\\copy1.png"); //works

Vesan's answer didn't helped me so I found an different solution.
So I can safe/open an image and if I want instantly delete the image.
i used it for my dataGridView_SelectionChanged:
private void dataGridViewAnzeige_SelectionChanged(object sender, EventArgs e)
{
var imageAsByteArray = File.ReadAllBytes(path);
pictureBox1.Image = byteArrayToImage(imageAsByteArray);
}
public Image byteArrayToImage(byte[] byteArrayIn)
{
MemoryStream ms = new MemoryStream(byteArrayIn);
Image returnImage = Image.FromStream(ms);
return returnImage;
}

All above answers are perfectly fine, but I've got a different approach.
Using Image abstract class, you will not get quite a lot of options for manipulating and resizing image.
Rather you do as follows:-
Bitmap img = new Bitmap(item);
img.SetResolution(100, 100);
Image imgNew = Image.FromHbitmap(img.GetHbitmap());
pictureBox1.Image = imgNew;
img.Dispose();

How to download PDF file into client system?

I want to download a PDF file from server side into client system. A Report page is changed into PDF file and saved into a project folder that is on server side. Here the problem is that when I access it from client system and try to generate PDF file then I am not sure whether it has successfully generated a PDF file into server side project folder or not and it is not automatically downloaded into the client system. But when I run project from local system then it is working correctly.
Here I post my code, please check it and please give me a solution for this, I need it very much
My code is:
protected void btn_print_Click(object sender, EventArgs e)
{
try
{
string url = HttpContext.Current.Request.Url.AbsoluteUri;
int width = 850;
int height = 550;
Thumbnail1 thumbnail = new Thumbnail1(url, 990, 1000, width, height);
Bitmap image = thumbnail.GenerateThumbnail();
image.Save(Server.MapPath("~") + "/Dwnld/Thumbnail.bmp");
imagepath = Server.MapPath("~").ToString() + "\\Dwnld\\" + "Thumbnail.bmp";
imagepath1 = Server.MapPath("~").ToString() + "\\Dwnld\\" + "Thumbnail.pdf";
convetToPdf();
}
catch (Exception)
{
throw;
}
}
string imagepath = null;
string imagepath1 = null;
public void convetToPdf()
{
PdfDocument doc = new PdfDocument();
System.Drawing.Size size = PageSizeConverter.ToSize(PdfSharp.PageSize.A4);
PdfPage pdfPage = new PdfPage();
pdfPage.Orientation = PageOrientation.Landscape;
doc.Pages.Add(pdfPage);
// XSize size = PageSizeConverter.ToSize(PdfSharp.PageSize.A4)
XGraphics xgr = XGraphics.FromPdfPage(doc.Pages[0]);
XImage img = XImage.FromFile(imagepath);
xgr.DrawImage(img, 0, 0);
doc.Save(imagepath1);
xgr.Dispose();
img.Dispose();
doc.Close();
Response.ContentType = "Application/pdf";
//Get the physical path to the file.
string FilePath = imagepath1;
//Write the file directly to the HTTP content output stream.
Response.WriteFile(FilePath);
Response.End();
}
public class Thumbnail1
{
public string Url { get; set; }
public Bitmap ThumbnailImage { get; set; }
public int Width { get; set; }
public int Height { get; set; }
public int BrowserWidth { get; set; }
public int BrowserHeight { get; set; }
public Thumbnail1(string Url, int BrowserWidth, int BrowserHeight, int ThumbnailWidth, int ThumbnailHeight)
{
this.Url = Url;
this.BrowserWidth = BrowserWidth;
this.BrowserHeight = BrowserHeight;
this.Height = ThumbnailHeight;
this.Width = ThumbnailWidth;
}
public Bitmap GenerateThumbnail()
{
Thread thread = new Thread(new ThreadStart(GenerateThumbnailInteral));
thread.SetApartmentState(ApartmentState.STA);
thread.Start();
thread.Join();
return ThumbnailImage;
}
private void GenerateThumbnailInteral()
{
WebBrowser webBrowser = new WebBrowser();
webBrowser.ScrollBarsEnabled = false;
webBrowser.Navigate(this.Url);
webBrowser.DocumentCompleted += new WebBrowserDocumentCompletedEventHandler(WebBrowser_DocumentCompleted);
while (webBrowser.ReadyState != WebBrowserReadyState.Complete) System.Windows.Forms.Application.DoEvents();
webBrowser.Dispose();
}
private void WebBrowser_DocumentCompleted(object sender, WebBrowserDocumentCompletedEventArgs e)
{
WebBrowser webBrowser = (WebBrowser)sender;
webBrowser.ClientSize = new Size(this.BrowserWidth, this.BrowserHeight);
webBrowser.ScrollBarsEnabled = false;
this.ThumbnailImage = new Bitmap(webBrowser.Bounds.Width, webBrowser.Bounds.Height);
webBrowser.BringToFront();
webBrowser.DrawToBitmap(ThumbnailImage, webBrowser.Bounds);
this.ThumbnailImage = (Bitmap)ThumbnailImage.GetThumbnailImage(Width, Height, null, IntPtr.Zero);
}
}
protected void CreateThumbnailImage(object sender, EventArgs e)
{
}

One potential problem with this code is that you're writing to the same files for every request. If there are multiple requests at the same time, some of them might fail.
To solve this you could write to the response stream directly, i.e.
protected void btn_print_Click(object sender, EventArgs e)
{
string url = HttpContext.Current.Request.Url.AbsoluteUri;
int width = 850;
int height = 550;
Thumbnail1 thumbnail = new Thumbnail1(url, 990, 1000, width, height);
using (Bitmap image = thumbnail.GenerateThumbnail())
convertToPdf(image);
}
public void convertToPdf(Image image)
{
using (PdfDocument doc = new PdfDocument())
{
System.Drawing.Size size = PageSizeConverter.ToSize(PdfSharp.PageSize.A4);
PdfPage pdfPage = new PdfPage();
pdfPage.Orientation = PageOrientation.Landscape;
doc.Pages.Add(pdfPage);
using (XGraphics xgr = XGraphics.FromPdfPage(doc.Pages[0]))
{
using (XImage img = XImage.FromGdiPlusImage(image))
{
xgr.DrawImage(img, 0, 0);
using (MemoryStream stream = new MemoryStream())
{
doc.Save(stream, false);
Response.ContentType = "application/pdf";
Response.AddHeader("Content-Length", stream.Length.ToString());
stream.WriteTo(Response.OutputStream);
}
}
}
}
Response.End();
}
Edit Modified answer to use using statements to release resources.

Download an image from the web and store in media library (windows phone 8)

i am trying to download an image from the web save it in the media library , below is my code, am i missing something here, Thanks in advance
public void storePicture()
{
try
{
using (IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication())
{
string url = #"http://mynokiablog.com/wp-content/uploads/2012/11/wp8.jpeg";
BitmapImage storeimage = new BitmapImage(new Uri(url));
// height and width are 0
int testheight = storeimage.PixelHeight;
int testwidth = storeimage.PixelWidth;
IsolatedStorageFileStream fileStream = myIsolatedStorage.CreateFile("testname");
// NullRefrenceException
WriteableBitmap wb = new WriteableBitmap(storeimage);
wb.SaveJpeg(fileStream, wb.PixelWidth, wb.PixelHeight, 0, 85);
fileStream.Close();
}
}
catch (Exception ex)
{
System.Diagnostics.Debug.WriteLine(ex.Message);
}
}

add event handler as below
storeimage.ImageOpened += bitmapImage_ImageOpened;
storeimage.ImageFailed += bitmapImage_ImageFailed;
storeimage.DownloadProgress += bitmapImage_DownloadProgress;
then in bitmapImage_DownloadProgress, create WritableBitMap and save

private void LoadIMG()
{
var bitmapImage = new BitmapImage { CreateOptions = BitmapCreateOptions.None };
bitmapImage.ImageOpened += bitmapImage_ImageOpened;
bitmapImage.ImageFailed += bitmapImage_ImageFailed;
bitmapImage.DownloadProgress += bitmapImage_DownloadProgress;
bitmapImage.UriSource = new Uri("http://ds.serving-sys.com/BurstingRes///Site-16990/Type-0/7b912e70-352a-454f-8ea7-5d5ecd6ebfae.gif");
}
private void bitmapImage_DownloadProgress(object sender, DownloadProgressEventArgs e)
{
}
private void bitmapImage_ImageFailed(object sender, ExceptionRoutedEventArgs e)
{
}
private void bitmapImage_ImageOpened(object sender, RoutedEventArgs e)
{
var userStoreForApplication = IsolatedStorageFile.GetUserStoreForApplication();
var writeableBitmap = new WriteableBitmap(sender as BitmapImage);
var isolatedStorageFileStream = userStoreForApplication.CreateFile("Myfile.gif");
writeableBitmap.SaveJpeg(isolatedStorageFileStream, writeableBitmap.PixelWidth, writeableBitmap.PixelHeight, 0, 85);
}

You can try it: http://www.kunal-chowdhury.com/2012/02/how-to-download-and-save-images-in-wp7.html#.TzUtWBSaLkM.twitter
Hope this helps.

How to pass a photo between pages in Windows Phone?

I know how to pass data through
NavigationService.Navigate(new Uri("/Second.xaml?msg=mesage", UriKind.Relative));
The question is, how can I pass an image selected from the library to another page?
To select an image, I use the PhotoChooserTask and in the event where it is completed I have this:
private void photoChooserTask_Completed(object sender, PhotoResult e)
{
if (e.ChosenPhoto != null)
{
BitmapImage image = new BitmapImage();
image.SetSource(e.ChosenPhoto);
this.img.Source = image;
}
}
How can I send the chosen photo to another page? Do I have to write it in a buffer, set a global variable or 'save' it in Isolated storage?

You could save your picture in IsolatedStorage first, pass the file path to another page as a string parameter, load the picture out when you need it.
Use PhoneApplicationService to save the image into State, load it when you need it.
Sample for saving into IsolatedStorage:
public static void SaveStreamToStorage(Stream imgStream, string fileName)
{
using (IsolatedStorageFile iso_storage = IsolatedStorageFile.GetUserStoreForApplication())
{
//Structure the path you want for your file.
string filePath = GetImageStorePathByFileName(fileName);
//Constants.S_STORE_PATH is the path I want to store my picture.
if (!iso_storage.DirectoryExists(Constants.S_STORE_PATH))
{
iso_storage.CreateDirectory(Constants.S_STORE_PATH);
}
//I skip the process when I find the same file.
if (iso_storage.FileExists(filePath))
{
return;
}
try
{
if (imgStream.Length > 0)
{
using (IsolatedStorageFileStream isostream = iso_storage.CreateFile(filePath))
{
BitmapImage bitmap = new BitmapImage();
bitmap.SetSource(imgStream);
WriteableBitmap wb = new WriteableBitmap(bitmap);
// Encode WriteableBitmap object to a JPEG stream.
Extensions.SaveJpeg(wb, isostream, wb.PixelWidth, wb.PixelHeight, 0, 100);
isostream.Close();
bitmap.UriSource = null;
bitmap = null;
wb = null;
}
}
}
catch(Exception e)
{
if (iso_storage.FileExists(filePath))
iso_storage.DeleteFile(filePath);
throw e;
}
}
}
Sample for reading picture from IsolatedStorage:
public static BitmapImage LoadImageFromIsolatedStorage(string imgName)
{
try
{
var bitmapImage = new BitmapImage();
//bitmapImage.CreateOptions = BitmapCreateOptions.DelayCreation;
using (var iso = IsolatedStorageFile.GetUserStoreForApplication())
{
//Check if file exists to prevent exception when trying to access the file.
if (!iso.FileExists(GetImageStorePathByFileName(imgName)))
{
return null;
}
//Since I store my picture under a folder structure, I wrote a method GetImageStorePathByFileName(string fileName) to get the correct path.
using (var stream = iso.OpenFile(GetImageStorePathByFileName(imgName), FileMode.Open, FileAccess.Read))
{
bitmapImage.SetSource(stream);
}
}
//Return the picture as a bitmapImage
return bitmapImage;
}
catch (Exception e)
{
// handle the exception
Debug.WriteLine(e.Message);
}
return null;
}

You could use a variable defined in your app.xaml.cs and call it from your other page like so (don't mind the variable names, just a code sample I use for language support):
private LanguageSingleton LanguageInstance
{
get
{
return (App.Current as App).Language;
}
}
Here is how you could define that variable:
public LanguageSingleton Language { get; set; }
I'm sure there are more ways in doing this but this is one solution.

Take image from video playing on windows media player in C#

In my windows application I use Windows Media Player dlls to play a video.
In my form I have a button to take a picture of the current video frame.
I did a lot of tests and code examinations but I couldn't find out why taking a picture of the current frame fails.
I tried this code, but the resulting image was black:
private Graphics g = null;
private void btnTakePicture_Click(object sender, EventArgs e)
{
if (!string.IsNullOrEmpty(axWMVMovie.URL))
{
axWMVMovie.Ctlcontrols.pause();
if (saveFileDialog1.ShowDialog() == DialogResult.OK)
{
System.Drawing.Image ret = null;
try
{
Bitmap bitmap = new Bitmap(axWMVMovie.Width, axWMVMovie.Height);
{
g = Graphics.FromImage(bitmap);
{
Graphics gg = axWMVMovie.CreateGraphics();
{
timerTakePicFromVideo.Start();
}
}
using (MemoryStream ms = new MemoryStream())
{
bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
ret = System.Drawing.Image.FromStream(ms);
ret.Save(saveFileDialog1.FileName);
}
}
}
catch
{
}
}
}
}
private void timerTakePicFromVideo_Tick(object sender, EventArgs e)
{
timerTakePicFromVideo.Stop();
g.CopyFromScreen(axWMVMovie.PointToScreen(new System.Drawing.Point()).X,
axWMVMovie.PointToScreen(new System.Drawing.Point()).Y, 0, 0,
new System.Drawing.Size(axWMVMovie.Width, axWMVMovie.Height));
}
I use Timer because when the user selects the save path, function takes image from the file user specified in save file dialog. Video format is WMV.

I took your code and modified it. I put the code to capture the photo a little bit up and now it works. I create the picture right before the saveFileDialog pops up, so you will really get only the picture and not the saveFileDialog within your pic.
if (!string.IsNullOrEmpty(axWindowsMediaPlayer1.URL))
{
axWindowsMediaPlayer1.Ctlcontrols.pause();
System.Drawing.Image ret = null;
try
{
// take picture BEFORE saveFileDialog pops up!!
Bitmap bitmap = new Bitmap(axWindowsMediaPlayer1.Width, axWindowsMediaPlayer1.Height);
{
Graphics g = Graphics.FromImage(bitmap);
{
Graphics gg = axWindowsMediaPlayer1.CreateGraphics();
{
//timerTakePicFromVideo.Start();
this.BringToFront();
g.CopyFromScreen(
axWindowsMediaPlayer1.PointToScreen(
new System.Drawing.Point()).X,
axWindowsMediaPlayer1.PointToScreen(
new System.Drawing.Point()).Y,
0, 0,
new System.Drawing.Size(
axWindowsMediaPlayer1.Width,
axWindowsMediaPlayer1.Height)
);
}
}
// afterwards save bitmap file if user wants to
if (saveFileDialog1.ShowDialog() == DialogResult.OK)
{
using (MemoryStream ms = new MemoryStream())
{
bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
ret = System.Drawing.Image.FromStream(ms);
ret.Save(saveFileDialog1.FileName);
}
}
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
}
}

With previous answer a trick to avoid getting the controls on the capture is to do this before you capture :
string uimode_previus = axWindowsMediaPlayer2.uiMode;
axWindowsMediaPlayer2.uiMode = "none";
then when capture is done set the uimode back to previous like this :
axWindowsMediaPlayer2.uiMode = uimode_previus ;
In that way you only get the actual shoot from the current frame.
it is a little workaround but it does the job.
Here is working example
private void button8_Click_1(object sender, EventArgs e)
{
string uimode_previus = axWindowsMediaPlayer2.uiMode;
axWindowsMediaPlayer2.uiMode = "none";
if (!string.IsNullOrEmpty(axWindowsMediaPlayer2.URL))
{
ret = null;
try
{
// take picture BEFORE saveFileDialog pops up!!
Bitmap bitmap = new Bitmap(axWindowsMediaPlayer2.Width, axWindowsMediaPlayer2.Height);
{
Graphics g = Graphics.FromImage(bitmap);
{
Graphics gg = axWindowsMediaPlayer2.CreateGraphics();
{
//timerTakePicFromVideo.Start();
this.BringToFront();
g.CopyFromScreen(axWindowsMediaPlayer2.PointToScreen(
new System.Drawing.Point()).X,
axWindowsMediaPlayer2.PointToScreen(
new System.Drawing.Point()).Y,
0, 0,
new System.Drawing.Size(
axWindowsMediaPlayer2.Width - 0,
axWindowsMediaPlayer2.Height - 0)
);
}
}
// afterwards save bitmap file if user wants to
try
{
using (MemoryStream ms = new MemoryStream())
{
string rute = axWindowsMediaPlayer2.URL.ToString().Replace(".", "Review_."); //
bitmap.Save(ms, System.Drawing.Imaging.ImageFormat.Png);
ret = new Bitmap(System.Drawing.Image.FromStream(ms));
ret.Save(rute.Replace(".mp4", ".Png"));
}
// open captured frame in new form
TeamEasy.ShowPictureForm spf = new ShowPictureForm();
spf.ImagePictureBox.Image = ret;
spf.ShowDialog();
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
}
}
}
catch (Exception ex)
{
Debug.WriteLine(ex.Message);
}
}
axWindowsMediaPlayer2.uiMode = uimode_previus;
// restore the UImode of player
}