Embedding of size in Stream

Question

I am embedding my size in a Stream in the first 4 byte. When I think about it, it should be possible to do it better, but that depends.

Here is how I currently do it:

bsize = ms.Length;
tcp.GetStream().Write(BitConverter.GetBytes(bsize), 0, intsize);
tcp.GetStream().Write(ms.GetBuffer(), 0, (int)bsize);

As you can see, it works and it's nothing weird. I just send 2 streams, the first being the length and the other being the data.

So, there aren't many things that can be done to improve or even change this.

But my idea is: why use 2 streams when you can probably embed the size immediately on the second, so you only need to write it once?

Sadly, I am not sure how to do that, or if it's even an improvement. Here is my testing code to achieve it:

bsize = ms.Length;
ms.Write(BitConverter.GetBytes(bsize), 0, intsize);
ms.Position = 0;
tcp.GetStream().Write(ms.GetBuffer(), 0, (int)bsize+4);

So, I thought: why can't you just write the length to the MemoryStream and add it before the actual data?

But, it doesn't work, and I am not sure if it's adding or overwriting data. I suppose it's overwriting, which means it won't work.

From my testing, I think Write adds data to the end, which complicates things.

Answer 1

I was looking into the MemoryStream and I found this

Except for a MemoryStream constructed with a byte[] parameter, write operations at the end of a MemoryStream expand the MemoryStream.

on MemoryStream.Write Method

I would look around a little bit on the MSDN sites that I am going to list and see if you want to change around the code that you have so that you can maybe use the Byte[] Parameter.

MemoryStream Class

although it looks like most of those Constructors create non-resizable instances, whereas the a Memory Stream Created with out any Parameters ...

Initializes a new instance of the MemoryStream class with an expandable capacity initialized to zero.

so to me it looks like the BlockCopy or 2 streams methods are the only way to go.

Answer 2

if you take and create two Byte[] Variables and fill the first with the information that you want to send then you can figure the size add it to the second Byte array and then append the information to the second array as well then just send the second Byte Array in your stream.

Check out the First Answer to this Question on StackOverflow

Best way to combine two or more byte arrays in C#

that first answer is very detailed so you should be able to figure it into your code, he even breaks down the performance of two methods of doing it.