Taglib NullException when saving Picture

Question

I'm Working on my own tag editor for Mp3 files. It's been good so far until I got stuck on saving the picture to the file. So I did a little searching and found out about these two ways but in both of them when I press the save button on my program a NullException occurs and says "value cannot be null" here are the two codes:

TagLib.Picture pic = TagLib.Picture.CreateFromPath(PicDir); //occurs here
TagLib.Id3v2.AttachedPictureFrame albumCoverPictFrame = new 
TagLib.Id3v2.AttachedPictureFrame(pic);
albumCoverPictFrame.MimeType = System.Net.Mime.MediaTypeNames.Image.Jpeg;
albumCoverPictFrame.Type = TagLib.PictureType.FrontCover;
TagLib.IPicture[] pictFrames = new IPicture[1];
pictFrames[0] = (IPicture)albumCoverPictFrame;
file.Tag.Pictures = pictFrames;

and this one:

System.Drawing.Image img = System.Drawing.Image.FromFile(PicDir); //occurs here
TagLib.Picture pic = new TagLib.Picture();
pic.Type = TagLib.PictureType.FrontCover;
pic.Description = "Cover";
pic.MimeType = System.Net.Mime.MediaTypeNames.Image.Jpeg;
MemoryStream ms = new MemoryStream();
img.Save(ms, System.Drawing.Imaging.ImageFormat.Jpeg);
ms.Position = 0;
pic.Data = TagLib.ByteVector.FromStream(ms);
file.Tag.Pictures = new TagLib.IPicture[] { pic };
ms.Close();

I can't find anything on Internet about a NullException on saving the pic with TagLib. I'm sure nothing is wrong with the picture directory or the picture itself, so the problem comes from elsewhere.

This is the part where I use showDialog

private void OpenPic_Click(object sender, EventArgs e)
{
    openFileDialog3.DefaultExt = "JPG";
    openFileDialog3.Filter = "JPEG Files (*.jpg)|*.jpg";
    openFileDialog3.Multiselect = false;
    openFileDialog3.FileName = "Choose the Photo";
    openFileDialog3.ShowDialog();
}

and here is the FileOk part:

private void Pic_FileOk(object sender, CancelEventArgs e)
{
    label21.Visible = true;
    PicDir = openFileDialog3.FileName;
    Aks = true;
}

But you know that `Image.FromFile()` expects the path to the picture (including the filename) and not only a directory. — Benjamin J., Mar 31 '18 at 08:00
So i found out that the openfiledialog is returning null but why?! After opening the file the openfiledialog1.FileName is null — Pooya Barati, Mar 31 '18 at 08:17
Here's [when or why OpenFileDialog returns null](https://stackoverflow.com/questions/1261910/when-does-microsoft-win32-openfiledialog-showdialog-return-null) — Lennart Stoop, Mar 31 '18 at 08:21
Maybe you could post your code which belongs to the `OpenFileDialog`. — Benjamin J., Mar 31 '18 at 08:36
And when does the first code get's executed? After the FileOk event? — Benjamin J., Mar 31 '18 at 10:29
It's difficult do solve the problem with that code. Maybe the value of the variable `PicDir` get's changed someone else? Have you tried to set a breakpoint on the line `PicDir = openFileDialog3.FileName;` and check the value of `openFileDialog3.FileName`. — Benjamin J., Mar 31 '18 at 11:37
@BenjaminJ. im writing the code in another project im sure there is no problem with the code if i just remove PicDir=openFileDialog3.FileName and place instead PicDir = C:\pic.jpg the code runs and does the job — Pooya Barati, Mar 31 '18 at 19:49
Have you tried debugging as mentioned in my code above? What value ist shown for `openFileDialog3.FileName` in the debugger? Does it show the value `null`? — Benjamin J., Mar 31 '18 at 20:20
@BenjaminJ.so i rewrited the project with the same code and it worked :| — Pooya Barati, Apr 27 '18 at 07:44

Taglib NullException when saving Picture

0 Answers0