Adding Values to a Byte Array

Question

I'm starting with the two values below:

finalString = "38,05,e1,5f,aa,5f,aa,d0";
string[] holder = finalString.Split(',');

I'm looping thru holder like so:

foreach (string item in holder)
{
  //concatenate 0x and add the value to a byte array
}

On each iteration I would like to concatenate a 0x to make it a hex value and add it to a byte array.

This is what I want the byte array to be like when I finish the loop:

byte[] c = new byte[]{0x38,0x05,0xe1,0x5f,0xaa,0x5f,0xaa,0xd0};

So far all my attempts have not been successful. Can someone point me in the right direction?

Answer 1

just create a new byte array which is the size of both arrays put together. Then insert one, and insert the second into the new buffer. array sizes in .net are non-mutable

another approach would be to use something like List, and then just loop through each array and add it

var buffer = new List<byte>();
foreach(var b in firstArray) buffer.Add(b);
foreach(var b2 in secondArray) buffer.Add(b2);

byte[] newArray = buffer.ToArray();

Answer 2

You don't have to concatenate the prefix "0x". This prefix is used by the C# compiler when parsing literals, but byte.Parse doesn't use it

byte[] myByteArray = new byte[holder.Length];
int i = 0;
foreach (string item in holder)
{
    myByteArray[i++] = byte.Parse(item, System.Globalization.NumberStyles.AllowHexSpecifier); 
}

Answer 3

You can do this as a one-liner:

var c = holder.Select(s => byte.Parse(s, NumberStyles.AllowHexSpecifier)).ToArray();

c is now a byte array with the data you need.

Answer 4

This will generate the list of byte values based on the comma separated hex values you have:

     string hex_numbers = "38,05,e1,5f,aa,5f,aa,d0";
     string[] hex_values = hex_numbers.Split(new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
     byte[] byte_array = new byte[hex_values.Length];
     for(int i = 0; i < hex_values.Length; i++)
     {
        byte_array[i] = byte.Parse(hex_values[i], System.Globalization.NumberStyles.AllowHexSpecifier);
     }