Hex search and replace

Question

Hello, im trying to do an bytes replacer in a .bin file.

I need to search this value in file
08 01 10 05 30 08 81 22

And replace it with
90 81 19 40 00 78 41 00

I've used fileContents = fileContents.Replace(Convert.ToChar(&H08) but seems my file gets weird.
Thanks

Answer 1

Use File.ReadAllBytes / File.WriteAllBytes

You can find samples on Google, like :

How to Find and Replace Hexadecimal Characters in a text File Using VB.net

Find & replace hex values in a .dll file using C#

Answer 2

Thanks Castorix31