Converting the Uploaded File into a Byte Array with C#

This technical article was first published on 2022-12-19. Code samples reflect the library versions of that time; test them against current versions before use.

How to Convert an Uploaded File to Byte Array with C#?

Everyone who has coded in C# has done file uploads. We always perform more than one variation when uploading files. In this article, we will look at how to convert the uploaded file into byte[].

First of all, specific upload codes must be written for the platform on which the upload will be made. In this article, only the back-end codes after the file is sent to upload are available.

If we look at our method that will perform the operation immediately, it will be as follows;

public static byte[] ReadFully(Stream input)
        {
            byte[] buffer = new byte[16 * 1024];
            using (MemoryStream ms = new MemoryStream())
            {
                int read;
                while ((read = input.Read(buffer, 0, buffer.Length)) > 0)
                {
                    ms.Write(buffer, 0, read);
                }
                return ms.ToArray();
            }
        }

This method accepts Stream as a parameter. In other words, it refers to the file to be loaded. We can explain an example scenario that may occur while loading the file by coding as follows;

HttpPostedFile uploadFile = HttpContext.Current.Request.Files["file"];
byte[] DOSYA = ReadFully(uploadFile.InputStream);

Thus, we convert the uploaded file into byte[]. What we do next will depend on your needs.

We wish everyone good work.