Hex / Binary

[francisstokes]

byte[] buff = new byte[4];
buff[0] = 0x34;
buff[1] = 0x23;
buff[2] = 0x00;
buff[3] = 0xF2;


FileStream fs = new FileStream("hex.bin", FileMode.Create, FileAccess.ReadWrite);
BinaryWriter bw = new BinaryWriter(fs);
bw.Write(buff);
bw.Close(); 
Console.WriteLine("Written to file : hex.bin");

Right. That writes (34 23 00 F2) to a file in binary (specifically NOT text).

I would like to read a hex number (lets just say 342300F2) from a text file and encode that same hex number to a binary file. I cant work out how to process the text into binaray. Any ideas?