正在使用的文件（未打开）c＃

Question

I got a strange error with this program, It download a photo from internet, then I convert it to .jpeg and then I delete the first photo (in .png). But i got an error: File is being used by another process. Why is happening this? I didn't open the file, and nobody is using it.

string outFile;
outFile = Path.GetTempFileName();
try
{
    webClient.DownloadFile(foto, outFile);
    if (foto.Substring(foto.Length - 3) == "png")
    {
        System.Drawing.Image image1 = System.Drawing.Image.FromFile(outFile);
        foto = foto.Remove(foto.Length - 3) + "jpg";
        string outFile2 = Path.GetTempFileName();
        image1.Save(outFile2, System.Drawing.Imaging.ImageFormat.Jpeg);
        System.IO.File.Delete(outFile);                      
        outFile = outFile2;
    }
}

Answer 1

FromFile is keeping the file open, you have to use something like this:

// Load image
FileStream filestream;
filestream = new FileStream("Filename",FileMode.Open, FileAccess.Read);
currentImage = System.Drawing.Image.FromStream(filestream);
filestream.Close();

Answer 2

The system.Drawing.Image is holding on to the file, Just wrap the image1 in a using statement.

        string foto = "http://icons.iconarchive.com/icons/mazenl77/I-like-buttons/64/Style-Config-icon.png";
        string outFile = Path.GetTempFileName(); 
        WebClient webClient = new WebClient();
        try
        {
            webClient.DownloadFile(foto, outFile);
            if (Path.GetExtension(foto).ToUpper() == ".PNG")
            {
                string outFile2 = Path.GetTempFileName();
                using (System.Drawing.Image image1 = System.Drawing.Image.FromFile(outFile))
                {
                    image1.Save(outFile2, System.Drawing.Imaging.ImageFormat.Jpeg);
                }
                System.IO.File.Delete(outFile);
            }
        }