Question

I am doing image Read/Copy operations in WPF application. Please look at following piece of code:

try
{
  if (sourceDir != "")
    File.Copy(sourceDir, Path.Combine(backupDir, ecode + ".jpg"), true);
}
catch (Exception exx)
{
    MessageBox.Show(exx.ToString());
}

Now let explain problem with a scenario:
First time when this code executes the sourceDir and Path.Combine(backupDir, ecode + ".jpg") values are:
sourceDir=”C:\Users\Public\Pictures\Sample Pictures\Desert.jpg”
Path.Combine(backupDir, ecode + “.jpg”)=”D:\IEPL-archives-Do not Modify\DATA\654.jpg”

It works fine for the first time and file is being copied to its destination folder.

But for the second time when this code executes with following values:
sourceDir=”C:\Users\Public\Pictures\Sample Pictures\Penguins.jpg”
Path.Combine(backupDir, ecode + “.jpg”)=”D:\IEPL-archives-Do not Modify\DATA\654.jpg”

It throws following exception:

I am also displaying same image in UI, that is causing this exception. Here is the code which displays the image in UI:

image1.Source = new BitmapImage(new Uri(GetPicture(txtBarcode.Text), UriKind.RelativeOrAbsolute));
private string GetPicture(string _eid)
    {
        string picname = "";
        if (File.Exists(@"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".jpg"))
            picname = @"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".jpg";
        else if (File.Exists(@"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".jpeg"))
            picname = @"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".jpeg";
        else if (File.Exists(@"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".png"))
            picname = @"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".png";
        else if (File.Exists(@"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".gif"))
            picname = @"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".gif";
        else if (File.Exists(@"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".JPG"))
            picname = @"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".JPG";
        else if (File.Exists(@"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".JPEG"))
            picname = @"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".JPEG";
        else if (File.Exists(@"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".PNG"))
            picname = @"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".PNG";
        else if (File.Exists(@"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".GIF"))
            picname = @"D:\IEPL-archives-Do not Modify\DATA\" + _eid + ".GIF";
        else
            picname = @"Images\defaultPicture.jpg";
        return picname;
    }

Please suggest how can i modify the code so that this conflict will not arise?
Thanks

Answer 1

You should load the image into memory using BitmapCacheOption.OnLoad. That will release the lock on the file.

BitmapImage bi = new BitmapImage();
bi.BeginInit();

bi.CacheOption = BitmapCacheOption.OnLoad;
bi.UriSource = new Uri(GetPicture(txtBarcode.Text), UriKind.RelativeOrAbsolute);

// End initialization.
bi.EndInit();
image1.Source = bi;