Question

Why doesn’t the following code work (tested using Word documents and PDF files)?

The saved file launches the correct application, but it is corrupted and will not open.

OpenFileDialog openFileDialog1 = new OpenFileDialog();
if (openFileDialog1.ShowDialog() != DialogResult.OK)
    return;

string filename = openFileDialog1.FileName;
FileStream stream = File.OpenRead(filename);
byte[] array = new byte[stream.Length];

SaveFileDialog saveFileDialog1 = new SaveFileDialog();
saveFileDialog1.FileName = filename;
if (DialogResult.OK != saveFileDialog1.ShowDialog())
    return;

FileInfo fi = new FileInfo(saveFileDialog1.FileName);
using (FileStream fs = fi.OpenWrite())
{
    fs.Write(array, 0, array.Length);
}

Answer 1

Use the File byte array methods for better results.

Also, utilize using whenever you are working with disposable objects.

        byte[] array;
        string filename;

        using (OpenFileDialog openFileDialog1 = new OpenFileDialog())
        {
            if (openFileDialog1.ShowDialog() != DialogResult.OK) 
                return;
            filename = openFileDialog1.FileName;
            array = File.ReadAllBytes(filename);
        }

        using (SaveFileDialog saveFileDialog1 = new SaveFileDialog())
        {
            saveFileDialog1.FileName = filename;
            if (DialogResult.OK != saveFileDialog1.ShowDialog()) 
                return;
            File.WriteAllBytes(array);
        }