Is it possible to know if the type of the uploaded file is an image?

Question

While user uploading a file, is it possible to know if the uploaded file is an image or not,

I am open for any solution, Client Side, Server Side or both and we choose based on the case.

Answer 1

Yes, by checking the magic number of the file.

Answer 2

May be you can use following code to check if the file is an image.

public bool IsFileAnImage(string filePath)
{
   try
   {
      Image image = Image.FromFile(filePath))
   }
   catch
   {
      return false;   
   }
   finally
   {
      image.Dispose();
   }

   return true;
}

Answer 3

A simple way would be to look at the file's extension.