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deserializing data best practices

I have been given the task of deserializing some data. The data has all been munged into a string which is in the following format:
InternalNameA8ValueDisplay NameA¬InternalNameB8ValueDisplay NameB¬ etc etc.
(ie, it has an internal name, '8', the value, the display name, followed by '¬' **). for example, you'd have FirstName8JoeFirst Name¬
I have no control over how this data is serialized, its legacy stuff.
I've thought of doing a bunch of splits on the string, or breaking it up into a char array and splitting down the text that way. But this just seems horrible. This way there is too much that could go wrong (e.g, if the value of a phone number (for example), could begin with '8'.
What I want to know is what peoples' approaches to this would be? Is there anything more clever i can do to break the data down
note: '¬' isn't actually the character, it looks more like an arrow pointing left. but I'm away from my machine at the moment. Doh!
Thanks.

Instead of using splits, I would recommend using a simple state machine. Walk over each characters until you hit a delimiter, then you know you're on the next field. That takes care of issues like an "8" in a phone number.
NOTE - untested code ahead.
var fieldValues = new string[3];
var currentField = 0;
var line = "InternalNameA8ValueDisplay NameA¬InternalNameB8ValueDisplay NameB¬";
foreach (var c in line)
{
if (c == '8' && currentField == 0)
{
currentField++; continue;
}
if (c == '¬')
{
currentField++; continue;
}
fieldValues[currentField] += c;
}
Dealing with wonky formats - always a good time!
Good luck,
Erick

Constantly Incrementing String

So, what I'm trying to do this something like this: (example)
a,b,c,d.. etc. aa,ab,ac.. etc. ba,bb,bc, etc.
So, this can essentially be explained as generally increasing and just printing all possible variations, starting at a. So far, I've been able to do it with one letter, starting out like this:
for (int i = 97; i <= 122; i++)
{
item = (char)i
}
But, I'm unable to eventually add the second letter, third letter, and so forth. Is anyone able to provide input? Thanks.

Since there hasn't been a solution so far that would literally "increment a string", here is one that does:
static string Increment(string s) {
if (s.All(c => c == 'z')) {
return new string('a', s.Length + 1);
}
var res = s.ToCharArray();
var pos = res.Length - 1;
do {
if (res[pos] != 'z') {
res[pos]++;
break;
}
res[pos--] = 'a';
} while (true);
return new string(res);
}
The idea is simple: pretend that letters are your digits, and do an increment the way they teach in an elementary school. Start from the rightmost "digit", and increment it. If you hit a nine (which is 'z' in our system), move on to the prior digit; otherwise, you are done incrementing.
The obvious special case is when the "number" is composed entirely of nines. This is when your "counter" needs to roll to the next size up, and add a "digit". This special condition is checked at the beginning of the method: if the string is composed of N letters 'z', a string of N+1 letter 'a's is returned.
Here is a link to a quick demonstration of this code on ideone.

Each iteration of Your for loop is completely
overwriting what is in "item" - the for loop is just assigning one character "i" at a time
If item is a String, Use something like this:
item = "";
for (int i = 97; i <= 122; i++)
{
item += (char)i;
}

something to the affect of
public string IncrementString(string value)
{
if (string.IsNullOrEmpty(value)) return "a";
var chars = value.ToArray();
var last = chars.Last();
if(char.ToByte() == 122)
return value + "a";
return value.SubString(0, value.Length) + (char)(char.ToByte()+1);
}
you'll probably need to convert the char to a byte. That can be encapsulated in an extension method like static int ToByte(this char);
StringBuilder is a better choice when building large amounts of strings. so you may want to consider using that instead of string concatenation.

Another way to look at this is that you want to count in base 26. The computer is very good at counting and since it always has to convert from base 2 (binary), which is the way it stores values, to base 10 (decimal--the number system you and I generally think in), converting to different number bases is also very easy.
There's a general base converter here https://stackoverflow.com/a/3265796/351385 which converts an array of bytes to an arbitrary base. Once you have a good understanding of number bases and can understand that code, it's a simple matter to create a base 26 counter that counts in binary, but converts to base 26 for display.

Decrypting text using frequency analysis in c#.

I've been tasked with decrypting a text file using frequency analysis. This isn't a do it for me question but i have absolutley no idea what to do next. What i have so far reads in the text from file and counts the frequency of each letter. If someone could point me in the right direction as to swapping letters depending on their frequency it would be much appreciated.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;
namespace freqanaly
{
class Program
{
static void Main()
{
string text = File.ReadAllText("c:\\task_2.txt");
char[,] message = new char[2,26];
Console.Write(text); int count = 0;
for (int x = 'A'; x <= 'Z'; x++)
{
message[0, count] = (char)x;
Console.WriteLine(message[0, count]);
count++;
}
foreach (char c in text)
{ count = 0;
for (int x = 'A'; x <= 'Z'; x++)
{
if (c == x)
{
message[1, count]++;
}
count++;
}
}
Console.ReadKey();
for (int x = 0; x <= 25; x++)
{
Console.Write(message[0, x]); Console.Write(" = "); Console.WriteLine((int)message[1, x]);
}
Console.ReadKey();
}
}
}

This IS encrypted data, just using a simple subsitution cipher (I assume). See the definition of encoding/encrypting.
http://www.perlmonks.org/index.pl?node_id=66249
Regardless, as Sergey suggested, get a letter frequency table and match frequencies. You will have to take into account some deviation, since there is no guarantee there are exacltly 8.167% of 'A's in the document (perhaps in this document the percent of 'A's are 8.78 or 7.65%). Also, be sure to evaluate on every occurance of A, and not differentiate 'a' from 'A'. This can be handled with a simple ToUpper or ToLower transform on the character; just be consistant.
Also, when you start getting into less common, but still popular letters, you will need to handle that. C, F, G, W, and M are all around the 2% +/- mark, so you will need to play with the decrypted text till the letters fit in the word, and in other words within the document where this character substitution will also happen. This concept is similar to fitting numbers in a Suduko matrix. Luckily, once you find where a letter should go, it cascades through out the document and you can start to see the decrypted plain text emerge. As an example, '(F)it' and '(W)it' are both valid words, but if you see '(F)hen' in the document when you substitute a 'F', you can make a good guess that you should substitute this character with a 'W' instead. (T)here and (W)here is another example, and a word ()hen won't provide any guidance by itself, since both (W)hen and (T)hen are valid words. It is here you have to incorporate contextual clues as to which word makes sense. "Then is a good time to start our attack?" doesn't make as much sense as "When is a good time to start our attack?".
All of this is assusming you are using a monoalphebetic substitution. A polyalphebetic substitution is more difficult, and you may need to look into cracking the Vigenère cipher examples to try to figure out a way around this problem.
I suggest reading "The Code Book" by S. Singh. It is a very interesting read and easy to digest the historical ciphers used and how they were cracked.
http://www.google.com/products/catalog?q=the+code+book&rls=com.microsoft:en-us:IE-SearchBox&oe=&um=1&ie=UTF-8&tbm=shop&cid=5361323398438876518&sa=X&ei=hpR0T-HyObSK2QWvgvH-Dg&ved=0CFoQ8wIwBQ#

Next you should grab some of publically available English frequency lists (from Wikipedia, for example) and compare the actual frequencies table you got with it - in order to find the replacements for letters.

How do I detect lowercase keys using the Keys enum in C#?

for (Keys k = Keys.A; k <= Keys.Z; k++)
{
if (KeyPress(k))
Text += k;
}
This code detects the key buttons I pressed in my keyboard and it will print out what key is pressed in the console. However, I pressed 'a' on the keyboard but it comes out as 'A'. How do I fix this?

This is an often encountered problem. The trouble is that XNA isn't geared towards getting textual input from a keyboard. It's geared towards getting the current state of each key on the keyboard.
While you could write custom code to check things like whether shift is held down etc, what about keyboards that aren't the one you're using (e.g. different language, different layout). What most people do is get windows to do it for you.
If you want text to appear as expected you need to basically re-create a few things and get windows to do it for you.
See Promit's post here: http://www.gamedev.net/topic/457783-xna-getting-text-from-keyboard/
Usage:
Add his code to your solution. Call EventInput.Initialize in your game'sInitialize` method and subscribe to his event:
EventInput.CharEntered += HandleCharEntered;
public void HandleCharEntered(object sender, CharacterEventArgs e)
{
var charEntered = e.Character;
// Do something with charEntered
}
Note: If you allow any character to be inputted (e.g. foreign ones with umlauts etc.) make sure your SpriteFont supports them! (If not, maybe just check your font supports it before adding it to your text string or get the spritefont to use a special 'invalid' character).

After looking at your provided code, it should be a simple modification:
[...]
for (Keys k = Keys.A; k <= Keys.Z; k++)
{
if (KeyPress(k))
{
if (keyboardState.IsKeyDown(Keys.LeftShift) || keyboardState.IsKeyDown(Keys.RightShift)) //if shift is held down
Text += k.ToString().ToUpper(); //convert the Key enum member to uppercase string
else
Text += k.ToString().ToLower(); //convert the Key enum member to lowercase string
}
}
[...]

How best to program a 'field colorer' program - quite easy!

Sorry for the weird title, I could't think of anything better!
Anyways, I'm half way through writing a program (Windows Forms App) that reads in a fixed-width file, gathers field lengths from user input, then it's supposed to display each column from the first line of the file in a different color... Do you know what I mean? It's basically to differentiate between the different fields in a fixed-width file using color.
What I wanted to ask was what was the best way to go about this? Because I'm having a lot of trouble, and I keep running into things and just implementing disgusting solutions when I know there is a much better one.
Obviously you don't have to give me a whole program, just some ideas of better ways to go about this - because my solution is just horrendous.
Thank you all in advance!

I would use a RichTextBox. This has an easy way to change the color of text. Here is an example where I have 3 inputs from the user that tells how wide each column should be. Then it reads in a file and colors the widths appropriately. Hopefully this will give you some more ideas.
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
ReadFile();
}
private void ReadFile()
{
// Assumes there are 3 columns (and 3 input values from the user)
string[] lines_in_file = File.ReadAllLines(#"C:\Temp\FixedWidth.txt");
foreach (string line in lines_in_file)
{
int offset = 0;
int column_width = (int)ColumnWidth1NumericUpDown.Value;
// Set the color for the first column
richTextBox1.SelectionColor = Color.Khaki;
richTextBox1.AppendText(line.Substring(offset, column_width));
offset += column_width;
column_width = (int)ColumnWidth2NumericUpDown.Value;
// Set the color for the second column
richTextBox1.SelectionColor = Color.HotPink;
richTextBox1.AppendText(line.Substring(offset, column_width));
offset += column_width;
column_width = (int)ColumnWidth3NumericUpDown.Value;
// Make sure we dont try to substring incorrectly
column_width = (line.Length - offset < column_width) ?
line.Length - offset : column_width;
// Set the color for the third column
richTextBox1.SelectionColor = Color.MediumSeaGreen;
richTextBox1.AppendText(line.Substring(offset, column_width));
// Add newline
richTextBox1.AppendText(Environment.NewLine);
}
}
}