Question

On my website, I’m receiving image files for upload. I accept files of type jpg, png, bmp or gif. If the user uploads a jpg, png or gif I want to save the file keeping the file type, but if the user uploads a bmp I want to convert it to a png.

I have a method stub like this:

private void profileImgUpload(HttpPostedFile profileImg)

HttpPostedFile has a method saveAs, to save the file, or else a property InputStream to get a stream to work with.

In the previous implementation, someone had written this:

String[] allowedExtensions = { ".png", ".jpeg", ".jpg", ".gif" };
for (int i = 0; i < allowedExtensions.Length; i++)
    {
        if (FileExtension == allowedExtensions[i])
            FileOK = true;
    }
}

if (FileOK)
    profileImg.SaveAs(physicalPath + "newAvatarTemp.png");

I have assumed that this just results in the file being saved with the name newAvatarTemp.png, but the actual encoding type is not changed.

Answer 1

Looks like you dont convert the image, you just change the extension.

If you really want to convert check this out:

http://msdn.microsoft.com/en-us/library/9t4syfhh.aspx