Back to Basics – Reading a File into Memory Stream
Today I was asked to help a developer with a simple task she had. That task included reading an image file into a memory stream in order to send the image through an e-mail attachment. This post will show you how to do exactly that.
Reading a File into Memory Stream
Here is the code for reading the file into a memory stream:
using (FileStream fileStream = File.OpenRead(filePath))
MemoryStream memStream = new MemoryStream();
fileStream.Read(memStream.GetBuffer(), 0, (int)fileStream.Length);
That’s it for the reading part. Pay attention to use the using statement in order to dispose the FileStream after you use it.
Adding a MemoryStream as Attachment to a MailMessage
In order to use a stream as an attachment for an e-mail message object all you have to do is to write the following code:
msg.Attachments.Add(new Attachment(memStream, filename, MediaTypeNames.Image.Jpeg));
In the code sample msg is an instance of a MailMessage class, memStream is the MemoryStream (such as the memory stream from the previous code sample) and filename is the name of the file in the attachment. Since I know that the image is jpeg then I use the MediaTypeNames.Image.Jpeg.
Reading a file into a stream is a very basic thing to know. In the post I showed how to read an image into a memory stream and also how to attach it into a mail message object.