Refreshing Image Control To Display File Upload Preview - c#

Hi i'm trying to display a preview of an uploaded img in asp.net using the file upload control, i have a preview button where when the user clicks should save the file from the fileupload control into a temp folder on my server and change the imageurl of the imagecontrol to the path of the saved image in the temp folder and display the image on the page after a postback. Here is what i have done:
protected void btnPreview_1_Click(object sender, EventArgs e)
{
if (!imgUpload_1.HasFile)
{
return;
}
string strFileName = Path.GetFileNameWithoutExtension(imgUpload_1.FileName.ToString());
string ext = Path.GetExtension(imgUpload_1.FileName.ToString());
string loc = "temp/";
string strImgFolder = Server.MapPath(loc);
System.Drawing.Image newImage;
FileUpload img = (FileUpload)imgUpload_1;
Byte[] imgByte = null;
try
{
if (img.HasFile && img.PostedFile != null)
{
HttpPostedFile File = imgUpload_1.PostedFile;
imgByte = new Byte[File.ContentLength];
File.InputStream.Read(imgByte, 0, File.ContentLength);
}
}
catch (Exception ex)
{
}
if (imgByte != null)
{
using (MemoryStream stream = new MemoryStream(imgByte, 0, imgByte.Length))
{
newImage = System.Drawing.Image.FromStream(stream);
newImage.Save(strImgFolder + strFileName + ext);
imgPreview.ImageUrl = strImgFolder + strFileName + ext;
imgPreview.AlternateText = strFileName;
}
}
}
I've tried using a handler for this using code i found online and after hours of trying i still couldn't get it to work, i also tried attaching a random number to the end of the imageurl(like so imageurl + "?" + randomnumber to force the page to refresh(That didn't work either) and i also tried:
Response.AddHeader("Cache-Control", "no-cache");
in my page load even and that didn't work either.
I've been at it for hours could someone plz help me out?

Related

c# the image file is duplicated when I copy file to the folder

I am trying to browse multiple image files and copy them to another folder. So, what I do is when I browse the image I storeit in flowlayoutpanel first, after that I create a button to copy all the image from flowlayutpanel to the destination folder. Now,I have a problem when I copy to another folder even if it has a different file name. Any suggestions to solve this question.
*this is the code to copy file to folder.
private void button2_Click(object sender, EventArgs e)
{
foreach (TextBox tb1 in TextBoxes1)
{
MessageBox.Show(tb1.Text);
String[] files = openFileDialog1.FileNames;
String newDir = #"C:\Users\Public\Pictures\Sample Pictures\Modified";
System.IO.Directory.CreateDirectory(newDir);
Parallel.ForEach(files, (textboxes) =>
{
foreach (TextBox tb in TextBoxes)
{
String filename = System.IO.Path.GetFileName(tb.Text);
var bitmap = new Bitmap(textboxes);
String text = Path.Combine(newDir, filename);
string toDisplay = string.Join(Environment.NewLine, files);
MessageBox.Show(toDisplay);
bitmap.Save(text);
}
});
}
}
* this is the code how i browse the image file and show in flowlayout
private void button1_Click_2(object sender, EventArgs e)
{
DialogResult dr = this.openFileDialog1.ShowDialog();
if (dr == System.Windows.Forms.DialogResult.OK)
{
// Read the files
foreach (String file in openFileDialog1.FileNames)
{
// Create a PictureBox.
try
{
Panel panel = new Panel();
PictureBox pb = new PictureBox();
TextBox tb = new TextBox();
TextBox tb1 = new TextBox();
Image loadedImage = Image.FromFile(file);
pb.Height = 200;
pb.Width = 200;
pb.Image = loadedImage;
pb.SizeMode = PictureBoxSizeMode.StretchImage;
tb.Text = Path.GetFileName(openFileDialog1.FileName);
tb1.Text = openFileDialog1.FileName;
//panel.Controls.Add(pb);
panel.Controls.Add(tb);
panel.Controls.Add(tb1);
panel.Height = 200;
panel.Width = 200;
flowLayoutPanel1.Controls.Add(panel);
TextBoxes.Add(tb);
TextBoxes1.Add(tb1);
}
catch (SecurityException ex)
{
// The user lacks appropriate permissions to read files, discover paths, etc.
MessageBox.Show("Security error. Please contact your administrator for details.\n\n" +
"Error message: " + ex.Message + "\n\n" +
"Details (send to Support):\n\n" + ex.StackTrace
);
}
catch (Exception ex)
{
// Could not load the image - probably related to Windows file system permissions.
MessageBox.Show("Cannot display the image: " + file.Substring(file.LastIndexOf('\\'))
+ ". You may not have permission to read the file, or " +
"it may be corrupt.\n\nReported error: " + ex.Message);
}
}
}
I guess parallel.foreach is the culprit. You are using multiple threads when using Parallel.foreach
In other words, you have two threads doing the same thing.
I would suggest you to try with a simple foreach loop.

Image not uploading and getting "Cannot access a closed file."

I have been trying to upload images via a file upload control. The file is not being uploaded and I keep getting the following error:"Cannot access a closed file."
I am unsure as to why I am getting this error, any assistance would be appreciated.
My code: First is the code that grabs the image and creates the 'preview'
protected void btnupload_Click(Object sender, EventArgs e)
{
Session["Image"] = flupGalImg.PostedFile;
Stream fs = flupGalImg.PostedFile.InputStream;
BinaryReader br = new BinaryReader(fs);
byte[] bytes = br.ReadBytes((Int32)fs.Length);
string base64String = Convert.ToBase64String(bytes, 0, bytes.Length);
imgGalImg.ImageUrl = "data:image/png;base64," + base64String;
imgGalImg.Visible = true;
}
My code that calls my business logic code:
else if(btnaddedit.Text == "Add item")
{
if(txtItemTitle.Text != "")
{
if(txtItemDescription.Text != "")
{
if(Session["Image"] != null)
{
HttpPostedFile postedFile = (HttpPostedFile)Session["Image"];
int alb;
int.TryParse(hdnAlbId.Value, out alb);
if(newsLogic.CreateNewGalleryItem(txtItemTitle.Text, txtItemDescription.Text, alb, postedFile) == true)
{
// Do something.
}
}
}
}
}
And finally my business logic code:
// create gallery item
[System.ComponentModel.DataObjectMethodAttribute(System.ComponentModel.DataObjectMethodType.Insert, true)]
public bool CreateNewGalleryItem(string itemTitle, string itemDescription, int itemAlbum, HttpPostedFile itemFile)
{
string folderpath = #"~/Images/GalleryImages/";
string filename = Path.GetFileName(itemFile.FileName.ToString());
bool itemCreated = false;
string itemImgPath;
try
{
itemImgPath = Path.Combine(folderpath + filename);
string itemImgUploadPath = Path.Combine(HttpContext.Current.Server.MapPath(folderpath) + filename);
itemFile.SaveAs(itemImgUploadPath);
galAdp.CreateGalleryItem(itemTitle, itemDescription, itemImgPath, itemAlbum);
itemCreated = true;
}
catch (Exception er)
{
itemCreated = false;
string consmsg = er.Message;
}
return itemCreated;
}
My 'image preview' works just fine. The error is thrown on this line of the business logic: itemFile.SaveAs(itemImgUploadPath);
When I did a google search (well lots of google searches) I read that it may be the file size so I increased the max allowed content in the web.config but nothing changed.
Any ideas as to what I am doing wrong?

delete folder but the process cannot access the file because being used

so i made a simple project where when i click a button the picture edit get an image from a folder file, but when i want to delete the folder that contains the image, it gives me an error. the code as following
private void button1_Click(object sender, EventArgs e)
{
string pathx = AppDomain.CurrentDomain.BaseDirectory + "\\TempImage\\" + "naruto" + ".png";
pictureEdit1.Image = Image.FromFile(pathx);
}
private void button2_Click(object sender, EventArgs e)
{
string dir = AppDomain.CurrentDomain.BaseDirectory + "\\TempImage";
try {
if (Directory.Exists(dir))
{
//////give me an error in here///////
Directory.Delete(dir, true);
}
else
{
MessageBox.Show("folder not found");
}
}
catch (Exception ex)
{
MessageBox.Show(ex.Message);
}
}
the purpose of this, is in my main project, for cache purpose. so i get an image from a certain folder after coping it from server to local. and when i want to close the main project i need to clear the cache or folder
Update
which is better alternate 1 or alternate 2 (to dispose)
private void button1_Click(object sender, EventArgs e)
{
string pathx = AppDomain.CurrentDomain.BaseDirectory + "\\TempImage\\" + "naruto" + ".png";
//alternate1
using (FileStream stream = new FileStream(pathx, FileMode.Open, FileAccess.Read))
{
pictureEdit1.Image = Image.FromStream(stream);
//stream.Dispose();
}
//alternate2
//Image img = new Bitmap(pathx);
//pictureEdit1.Image = img.GetThumbnailImage(pictureEdit1.Width, pictureEdit1.Height, null, new IntPtr());
//img.Dispose();
}
The documentation on System.Drawing.Bitmap (http://msdn.microsoft.com/en-us/library/0cbhe98f.aspx) says:
The file remains locked until the Bitmap is disposed.
To get around this, you should replace this line:
pictureEdit1.Image = Image.FromFile(pathx);
With this:
Image img = new Bitmap(pathx);
pictureEdit1.Image = img.GetThumbnailImage(pictureEdit1.Width, pictureEdit1.Height, null, new IntPtr());
img.Dispose();
This should load the Bitmap only long enough to create a thumbnail version of the image for use in the PictureBox control, then dispose of it immediately, releasing the lock on the file but still displaying the image on the screen.
Hope this helps!
Edit: Here's the version using using that does the same thing:
using (Image img = new Bitmap(pathx)) {
pictureEdit1.Image = img.GetThumbnailImage(pictureEdit1.Width, pictureEdit1.Height, null, new IntPtr());
}

Deleting File which is displayed in picturebox

I am selecting file from openfiledialoge and displaying it in picturebox and its name in textbox when I click on delete button I am getting exception The process cannot access the file because it is being used by another process.
I searched a lot for this exception to get resolved but i didn't fine any of them working, when i tried closing file with imagename which is in textbox i.e the file i am displaying in picturebox ; using IsFileLocked method,this closes and deletes all files of particular directory path ,but how can I delete the only file shown in picturebox,where I am going wrong
public partial class RemoveAds : Form
{
OpenFileDialog ofd = null;
string path = #"C:\Users\Monika\Documents\Visual Studio 2010\Projects\OnlineExam\OnlineExam\Image\"; // this is the path that you are checking.
public RemoveAds()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
if (System.IO.Directory.Exists(path))
{
ofd = new OpenFileDialog();
ofd.InitialDirectory = path;
DialogResult dr = new DialogResult();
if (ofd.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
Image img = new Bitmap(ofd.FileName);
string imgName = ofd.SafeFileName;
txtImageName.Text = imgName;
pictureBox1.Image = img.GetThumbnailImage(350, 350, null, new IntPtr());
ofd.RestoreDirectory = true;
}
}
else
{
return;
}
}
private void button2_Click(object sender, EventArgs e)
{
//Image img = new Bitmap(ofd.FileName);
string imgName = ofd.SafeFileName;
if (Directory.Exists(path))
{
var directory = new DirectoryInfo(path);
foreach (FileInfo file in directory.GetFiles())
{ if(!IsFileLocked(file))
file.Delete();
}
}
}
public static Boolean IsFileLocked(FileInfo path)
{
FileStream stream = null;
try
{ //Don't change FileAccess to ReadWrite,
//because if a file is in readOnly, it fails.
stream = path.Open ( FileMode.Open, FileAccess.Read, FileShare.None );
}
catch (IOException)
{ //the file is unavailable because it is:
//still being written to or being processed by another thread
//or does not exist (has already been processed)
return true;
}
finally
{
if (stream != null)
stream.Close();
}
//file is not locked
return false;
}
}
Thanks in advance for any help
The (previously) accepted answer to this question is very poor practice. If you read the documentation on System.Drawing.Bitmap, in particular for the overload that creates a bitmap from a file, you will find :
The file remains locked until the Bitmap is disposed.
in your code you create the bitmap and store it in a local variable but you never dispose of it when you are done. This means your image object has gone out of scope but has not released its lock on the image file you are trying to delete. For all objects that implement IDisposable (like Bitmap) you must dispose of them yourself. See this question for example (or search for others - this is a very important concept!).
To correct the problem properly you simply need to dispose of the image when you are done with it :
if (ofd.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
Image img = new Bitmap(ofd.FileName); // create the bitmap
string imgName = ofd.SafeFileName;
txtImageName.Text = imgName;
pictureBox1.Image = img.GetThumbnailImage(350, 350, null, new IntPtr());
ofd.RestoreDirectory = true;
img.Dispose(); // dispose the bitmap object
}
Please do not take the advice in the answer below - you should nearly never need to call GC.Collect and if you need to do it to make things work it should be a very strong signal that you are doing something else wrong.
Also, if you only want to delete the one file (the bitmap you have displayed) your deletion code is wrong and will delete every file in the directory as well (this is just repeating Adel's point). Further, rather than keep a global OpenFileDialog object alive simply to store the file name, I would suggest getting rid of that and saving just the file info :
FileInfo imageFileinfo; //add this
//OpenFileDialog ofd = null; Get rid of this
private void button1_Click(object sender, EventArgs e)
{
if (System.IO.Directory.Exists(path))
{
OpenFileDialog ofd = new OpenFileDialog(); //make ofd local
ofd.InitialDirectory = path;
DialogResult dr = new DialogResult();
if (ofd.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
Image img = new Bitmap(ofd.FileName);
imageFileinfo = new FileInfo(ofd.FileName); // save the file name
string imgName = ofd.SafeFileName;
txtImageName.Text = imgName;
pictureBox1.Image = img.GetThumbnailImage(350, 350, null, new IntPtr());
ofd.RestoreDirectory = true;
img.Dispose();
}
ofd.Dispose(); //don't forget to dispose it!
}
else
{
return;
}
}
Then in your second button handler you can just delete the one file you are interested in.
private void button2_Click(object sender, EventArgs e)
{
if (!IsFileLocked(imageFileinfo))
{
imageFileinfo.Delete();
}
}
I had the same problem : I loaded a file in a PictureBox and when trying to delete it I got the same exception.
This occurred only when the image was displayed.
I tried them all :
picSelectedPicture.Image.Dispose();
picSelectedPicture.Image = null;
picSelectedPicture.ImageLocation = null;
and still got the same exception.
Then I found this on CodeProject : [c#] delete image which is opened in picturebox.
Instead of using PictureBox.Load() it creates an Image from the file and sets it as PictureBox.Image:
...
// Create image from file and display it in the PictureBox
Image image = GetCopyImage(imagePath);
picSelectedPicture.Image = image;
...
private Image GetCopyImage(string path) {
using (Image image = Image.FromFile(path)) {
Bitmap bitmap = new Bitmap(image);
return bitmap;
}
}
No more exceptions when I delete the file.
IMHO, this is the most suitable solution.
EDIT
I forgot to mention that you can safely delete the file immediately after display :
...
// Create image from file and display it in the PictureBox
Image image = GetCopyImage(imagePath);
picSelectedPicture.Image = image;
System.IO.File.Delete(imagePath);
...
use this code
string imgName = ofd.SafeFileName;
if (Directory.Exists(path))
{
var directory = new DirectoryInfo(path);
foreach (FileInfo file in directory.GetFiles())
{
GC.Collect();
GC.WaitForPendingFinalizers();
file.Delete();
}
}
Your button2_Click event handler is cycling through all the files inside your directory & doing the deletes.
You need to change your code like the following:
public partial class RemoveAds : Form
{
OpenFileDialog ofd = null;
string path = #"C:\Users\Monika\Documents\Visual Studio 2010\Projects\OnlineExam\OnlineExam\Image\"; // this is the path that you are checking.
string fullFilePath;
public RemoveAds()
{
InitializeComponent();
}
private void button1_Click(object sender, EventArgs e)
{
if (System.IO.Directory.Exists(path))
{
ofd = new OpenFileDialog();
ofd.InitialDirectory = path;
DialogResult dr = new DialogResult();
if (ofd.ShowDialog() == System.Windows.Forms.DialogResult.OK)
{
Image img = new Bitmap(ofd.FileName);
string imgName = ofd.SafeFileName;
txtImageName.Text = imgName;
pictureBox1.Image = img.GetThumbnailImage(350, 350, null, new IntPtr());
fullFilePath = ofd.FilePath;
ofd.RestoreDirectory = true;
}
}
else
{
return;
}
}
private void button2_Click(object sender, EventArgs e)
{
FileInfo file = new FileInfo(fullFilePath);
if(!IsFileLocked(file))
file.Delete();
}
}
public static Boolean IsFileLocked(FileInfo path)
{
FileStream stream = null;
try
{ //Don't change FileAccess to ReadWrite,
//because if a file is in readOnly, it fails.
stream = path.Open ( FileMode.Open, FileAccess.Read, FileShare.None );
}
catch (IOException)
{ //the file is unavailable because it is:
//still being written to or being processed by another thread
//or does not exist (has already been processed)
return true;
}
finally
{
if (stream != null)
stream.Close();
}
//file is not locked
return false;
}
}
By using GetThumnailImage you have to specify the width and height which is static.
Use the Load method instead.
eg: pictureBox1.Load(Path to the image); by using this u will have no problem in deleting the image or the folder before closing the app. no other methods need to be created.
hope this helps

How to load image from isolated storage for secondary tile

I am attempting to populate a secondary tile background with an image saved from the PhotoChooserTask, but for some reason I cannot accomplish this. I have referenced a lot of sites but I have not found the proper implementation. All I do is call PhotoChooserTask, and then on the completed event I save the resulting image to isolated storage to be loaded later. This has worked with a HubTile in my application, but for some reason I cannot append the image to a secondary tile. So far what I have is as follows:
MainPage.xaml.cs
string imageFolder = #"\Shared\ShellContent";
string shareJPEG = "shareImage.jpg";
public MainPage()
{
InitializeComponent();
photoChooserTask = new PhotoChooserTask();
photoChooserTask.Completed += new EventHandler<PhotoResult>(photoChooserTask_Completed);
}
public void changePictureMenuItem_Tap(object sender, System.Windows.Input.GestureEventArgs e)
{
try
{
photoChooserTask.Show();
}
catch (System.InvalidOperationException)
{
MessageBox.Show("An error occurred");
}
}
void photoChooserTask_Completed(object sender, PhotoResult e)
{
if (e.TaskResult == TaskResult.OK)
{
//persist the data in isolated storage
using (IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication())
{
if(!myIsolatedStorage.DirectoryExists(imageFolder))
{
myIsolatedStorage.CreateDirectory(imageFolder);
}
if (myIsolatedStorage.FileExists(shareJPEG))
{
myIsolatedStorage.DeleteFile(shareJPEG);
}
string filePath = System.IO.Path.Combine(imageFolder, shareJPEG);
IsolatedStorageFileStream fileStream = myIsolatedStorage.CreateFile(filePath);
BitmapImage bitmap = new BitmapImage();
bitmap.SetSource(e.ChosenPhoto);
WriteableBitmap wb = new WriteableBitmap(bitmap);
// Encode WriteableBitmap object to a JPEG stream.
Extensions.SaveJpeg(wb, fileStream, 173, 173, 0, 100);
fileStream.Close();
}
}
}
private void CreateLiveTile(TileItem item)
{
//IsolatedStorageFile myIsolatedStorage = IsolatedStorageFile.GetUserStoreForApplication();
var title = item.Title.ToString();
string tileParameter = "Param=" + item.Title.ToString();
ShellTile Tile = CheckIfTileExist(tileParameter); // Check if Tile's title has been used
if (Tile == null)
{
//this is not working?
background = new Uri(#"isostore:/Shared/ShellContent/shareJPEG.png", UriKind.Absolute);
//background = new Uri("isostore:/Shared/ShellContent/shareJPEG.png", UriKind.Absolute);
try
{
var LiveTile = new StandardTileData
{
Title = item.TileName,
BackgroundImage = background, //not working
BackTitle = item.TileName,
BackBackgroundImage = new Uri("/background.png", UriKind.Relative),
BackContent = item.Message,
};
ShellTile.Create(new Uri("/MainPage.xaml?" + tileParameter, UriKind.Relative), LiveTile);
}
}
Ultimately, the secondary tile is created but there is no image for the BackgroundImage. How would I properly call the isolated strorage path to set the BackgroundImage of the secondary tile accordingly? Or is there something else I should be doing or change?
MainPage.xaml.cs
string imageFolder = #"\Shared\ShellContent";
string shareJPEG = "shareImage.jpg";
...
private void CreateLiveTile(TileItem item)
{
var title = item.Title.ToString();
string tileParameter = "Param=" + item.Title.ToString();
ShellTile Tile = CheckIfTileExist(tileParameter); // Check if Tile's title has been used
if (Tile == null)
{
string filePath = System.IO.Path.Combine(imageFolder, shareJPEG);
background = new Uri(#"isostore" + filePath, UriKind.Absolute); //this worked
...
}
}
Are you sure the image is saved successfully and exists? You save it as jpeg but you reference a png file. Try #"\Shared\ShellContent\shareJPEG.png"
first you should put your image at "\Shared\ShellContent" location. you can use .png or .jpg file
string imageFolder = #"\Shared\ShellContent";
string shareJPEG = "shareImage.jpg";
...
private void CreateLiveTile(TileItem item)
{
var title = item.Title.ToString();
string tileParameter = "Param=" + item.Title.ToString();
ShellTile Tile = CheckIfTileExist(tileParameter);
if (Tile == null)
{
string filePath = System.IO.Path.Combine(imageFolder, shareJPEG);
using (var iso = IsolatedStorageFile.GetUserStoreForApplication())
{
if (iso.FileExists(filePath)) // check file exist or not
background = new Uri(#"isostore:" + filePath, UriKind.Absolute);
}
...
}
}

Categories