Question

My ASP.NET application has an image cropping and resizing features. This requires that the uploaded temporary image be deleted. Everything works fine, but when I try to delete an image larger than 80px by 80px I get a “File is locked by another process…” error, even though I’ve released all resources.

Here’s a snippet:

System.Drawing.Image tempimg = System.Drawing.Image.FromFile(temppath);
System.Drawing.Image img = (System.Drawing.Image) tempimg.Clone(); //advice from another forum
tempimg.Dispose();

img = resizeImage(img, 200, 200); //delete only works if it's 80, 80
img.Save(newpath);
img.Dispose();

File.Delete(temppath);

Answer 1

I think you are not disposing the first Image instance assigned to the img variable.

Consider this instead:

System.Drawing.Image tempimg = System.Drawing.Image.FromFile(temppath);
System.Drawing.Image img = (System.Drawing.Image) tempimg.Clone();
tempimg.Dispose();

System.Drawing.Image img2 = resizeImage(img, 200, 200);
img2.Save(newpath);
img2.Dispose();
img.Dispose();

File.Delete(temppath);