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How to set string values into an enumerator

I have one string that contains integers and strings, separated by a comma.
For example:
0, Link Alive,1, Link Dead,2, Link Weak,3, Wiznet 0 Dead,4, Wiznet 1 Dead,5, Wiznets Dead
I want to make an enum out of this string like this:
public enum myEnums {
Link Alive = 0,
Link Dead = 2,
Link Weak = 1,
Wiznet 0 Dead = 3,
Wiznet 1 Dead = 4,
Wiznets Dead = 5
}
I was thinking about changing the string into a char array. After that I loop through the char array.
If I detect an integer, I assign its value to a temporary integer value. If I detect a string, I assign its value to a temporary string. After this I'll assign the temporary integer and string to an enumerator.
Only thing is, I don't know how to deal with the comma and the equal sign.
Can someone show me how it's supposed to be done?

It sounds to me like what you really ought to be doing is creating a Dictionary<string,int> since unless you are going to generate code, you can't change an enum at runtime, it's constant.
Now looking at your string:
0, Link Alive,1, Link Dead,2, Link Weak,3, Wiznet 0 Dead,4, Wiznet 1 Dead,5, Wiznets Dead
It looks like you have a set of comma delimited values. So split on , and then each pair of values is an int and a string. Make that you dictionary.
So a simple way to do that might look like this (assuming your data is good, i.e. it has a even number of items and every odd item actually can be parsed as an int):
var dict = new Dictionary<int,string>();
var cells = source.Split(',');
for (var i=0; i < cells.Length; i+=2)
{
dict[int.Parse(cells[i])] = cells[i+1].Trim(); // Note: you might want to check boundaries first!
}
Or using Linq, you could do something like this:
string source = "0, Link Alive,1, Link Dead,2, Link Weak,3, Wiznet 0 Dead,4, Wiznet 1 Dead,5, Wiznets Dead";
var dict = source.Split(',')
.Select((v,i) => new { v, i })
.GroupBy(x => x.i/2)
.ToDictionary(x => int.Parse(x.First().v), x => x.Skip(1).First().v.Trim());
Here's a fiddle.
To explain what we are doing here:
First with Split your string on ,. This give us a string array with ["0","Link Alive","1","Link Dead",...]
Next we use Select to select each item and it's index in a pair. So now we have a collection of objects that looks something like [{v="0",i=0},{v="Link Alive",i=1},...]
Now we group this by dividing the index by 2. Because this is integer division, it will truncate. So 0/2 == 0 and 1/2 == 0 and 2/2 == 1 and 3/2 == 1. So we are sorting into pairs of values.
Finally we convert these groups (which we know are pairs of values) into a dictionary. To do that we use the first item in each group and parse it into an int and use that as the key for our dictionary. Then we use the second value as the value. This finally gives us our dictionary
Now with you dictionary, if you want to look up a value, it's easy:
var myValue = dict[2]; // myValue is now "Link Weak"

By enumerator I assume you mean something over which you can iterate. An 'enum' is basically a set of named integers.
So if you have a string of items separated by commas and want to 'iterate' over them, then this may help:
string input = "0, Link Alive,1, Link Dead,2, Link Weak,3, Wiznet 0 Dead,4, Wiznet 1 Dead,5, Wiznets Dead"
string[] parts = input.split(new char[] {','}, StringSplitOptions.RemoveEmptyEntries);
foreach (string part in parts)
{
// do something
}

Prepare default new line as replacement of empty values

I'm working on reporting using rdlc where the report footer position needs to stay at bottom, but the four table footer visibility depend on certain condition.
For that I use Union and use Take(4) to make sure if any of the table footer is not visible it should be replaced with \r\n at the bottom.
Should be:
12345
\r\n
\r\n
\r\n
Not like this:
\r\n
\r\n
\r\n
12345
Here is my code.
var footerValues = new[]
{
salesOrder.Subtotal.ToString("N0"),
salesOrder.Discount.ToString("N0"),
salesOrder.PPN.ToString("N0"),
salesOrder.Total.ToString("N0")
};
var stats = new[] {
salesOrder.Discount >= 1 || salesOrder.PPN >= 1, // combined visibility
salesOrder.Discount >= 1, // visible only if the value >= 1
salesOrder.PPN >= 1, // visible only if the value >= 1
true // total always visible
};
var textValues = stats
.Select((v, i) => v ? footerValues[i] : null).OfType<string>()
.Union(Enumerable.Range(0, 4).Select(x => string.Empty).ToArray())
.Take(4)
.ToArray()
var footerValue = string.Join(Environment.NewLine, textValues);
If the stats produces
false, false, false, true
The expected footerValue would be
"12345\r\n\r\n\r\n\r\n"
But actual result is
"12345\r\n"
What's wrong with the code? Or can it be simplified?

This part:
.Union(Enumerable.Range(0, 4).Select(x => string.Empty).ToArray())
is pointless. it will only return one string.Empty. Because Union removes the duplicates. I think you want Concat instead.Btw, you can also replace Enumerable.Range with Enumerable.Repeat
var textValues = stats
.Select((v, i) => v ? footerValues[i] : null).OfType<string>()
.Concat(Enumerable.Repeat(string.Empty, 4))
.Take(4)
.ToArray();

LINQ non-linear order by string length

I'm trying to get a list of string ordered such that the longest are on either end of the list and the shortest are in the middle. For example:
A
BB
CCC
DDDD
EEEEE
FFFFFF
would get sorted as:
FFFFFF
DDDD
BB
A
CCC
EEEEE
EDIT: To clarify, I was specifically looking for a LINQ implementation to achieve the desired results because I wasn't sure how/if it was possible to do using LINQ.

You could create two ordered groups, then order the first group descending(already done) and the second group ascending:
var strings = new List<string> {
"A",
"BB",
"CCC",
"DDDD",
"EEEEE",
"FFFFFF"};
var two = strings.OrderByDescending(str => str.Length)
.Select((str, index) => new { str, index })
.GroupBy(x => x.index % 2)
.ToList(); // two groups, ToList to prevent double execution in following query
List<string> ordered = two.First()
.Concat(two.Last().OrderBy(x => x.str.Length))
.Select(x => x.str)
.ToList();
Result:
[0] "FFFFFF" string
[1] "DDDD" string
[2] "BB" string
[3] "A" string
[4] "CCC" string
[5] "EEEEE" string

Don't ask how and why... ^^
list.Sort(); // In case the list is not already sorted.
var length = list.Count;
var result = Enumerable.Range(0, length)
.Select(i => length - 1 - 2 * i)
.Select(i => list[Math.Abs(i - (i >> 31))])
.ToList();
Okay, before I forget how it works, here you go.
A list with 6 items for example has to be reordered to this; the longest string is at index 5, the shortest one at index 0 of the presorted list.
5 3 1 0 2 4
We start with Enumerable.Range(0, length) yielding
0 1 2 3 4 5
then we apply i => length - 1 - 2 * i yielding
5 3 1 -1 -3 -5
and we have the non-negative part correct. Now note that i >> 31 is an arithmetic left shift and will copy the sign bit into all bits. Therefore non-negative numbers yield 0 while negative numbers yield -1. That in turn means subtracting i >> 31 will not change non-negative numbers but add 1 to negative numbers yielding
5 3 1 0 -2 -4
and now we finally apply Math.Abs() and get
5 3 1 0 2 4
which is the desired result. It works similarly for lists of odd length.

Just another option, which I find more readable and easy to follow:
You have an ordered list:
var strings = new List<string> {
"A",
"BB",
"CCC",
"DDDD",
"EEEEE",
"FFFFFF"};
Create a new list and simply alternate where you add items::
var new_list = new List<string>(); // This will hold your results
bool start = true; // Insert at head or tail
foreach (var s in strings)
{
if (start)
new_list.Insert(0,s);
else
new_list.Add(s);
start = !start; // Flip the insert location
}
Sweet and simple :)
As for Daniel Bruckner comment, if you care about which strings comes first, you could also change the start condition to:
// This will make sure the longest strings is first
bool start= strings.Count()%2 == 1;

Find similarities in a binary string

I am currently trying to write a function that would help me find similarities between binary strings. This sounds vague so I will explain with an example.
StringA : 10111010000
StringB : 10111010011
StringC : 10111101111
I want my program to be able to find any similarities (4 digits or more) occuring at the same index. In the above example, my function would return : 0-4 (because caracters 0 to 4 are identical in all three strings).
I am not looking for code, just a logical and optimal way of doing this.

String is Array of Char.
You should do Loop in which you would compare each char.
For Example: (I had to put example, sorry)
for(int i=0;i<=length;i++) \\length = array lenght
{
if(StringA[i]==StringB[i]) CounterA++; \\or something like this
}

method 1: split the strings into either an Array, or a List, then use LINQ to find the groupings within the list...
method 2: loop through each string, then through each character, then create a new string with the character length, and compare to the same substring on the other strings...

Assuming all three items are stored in their own respective variables, I would split all of the bits into an array. From there, I would iterate through one array (since all of the arrays are the same size) and match from there. This operation would be O(n) since you have to look at n items.

Pseudocode?
array := array[numbers]
for each binary number
for each binary number
if numbers have the same binary digit at current index
array[index] := array[index] + 1
end
end
end

Iterate each character in the string, if they match add to a counter:
private static int GetDifferences(string firstStr, string secondStr)
{
int val = 0;
char[] first = firstStr.ToCharArray();
char[] second = secondStr.ToCharArray();
for (int i = 0; i < first.Length; i++)
{
if (first[i] == second[i])
{
val++;
}
}
return val;
}
By no means perfect but should get you started

i'd split them into a list:
static void Main()
{
var a = "10111010000";
var b = "10111010011";
var c = "10111101111";
var aList = Split(a, 4); //Use a custom split method
var bList = Split(b, 4);
var cList = Split(c, 4);
Dictionary<int,string> hits = new Dictionary<int, string>();
for (int i = 0; i < aList.Count(); i++)
{
if(aList[i] == bList[i] && bList[i] == cList[i])
hits.Add(i,aList[i]);
}
}

Probably you could use Bitwise operators:
get XOR result from A/B (say:A^B) and A/C (say:A^C)
get NOT result of step 1: ~(A^B); ~(A^C)
get And result from step 2: (~(A^B))&(~(A^C))
get the 1 part from step 3.
e.g.:
1.
A^B=10111010000^
10111010011
=00000000011;
A^C=10111010000^
10111101111
=00000111111
2.
~(A^B)=~(00000000011)=11111111100;
~(A^C)=~(00000111111)=11111000000;
3.
(~(A^B))&(~(A^C)) =11111111100&
11111000000
=11111000000

If you were just wanting to get a true or false as to whether there is a minimum of 4 matching characters, you could do this:
Public Function StringsHaveMin4CharsInCommon(ByVal StringA As String, ByVal StringB As String, ByVal StringC As String) As Boolean
Dim bReturn As Boolean
Dim iCounter As Integer
For i As Integer = 0 To StringA.Length - 1
If StringA.SubString(i, 1) = StringB.SubString(i, 1) And StringB.SubString(i, 1) = StringC.SubString(i, 1) Then iCounter += 1
If iCounter = 4 Then
bReturn = True
Exit For
End If
Next i
Return bReturn
End Function
If you wanted to retrieve the matching array indices then you would need to add logic to the same procedure to add each matching index to an Integer array and return that array from the function as follows.
Public Function GetCommonIndices(ByVal StringA As String, ByVal StringB As String, ByVal StringC As String) As Integer()
Dim iReturn() As Integer
Dim iCounter As Integer = -1
For i As Integer = 0 To StringA.Length - 1
If StringA.SubString(i, 1) = StringB.SubString(i, 1) And StringB.SubString(i, 1) = StringC.SubString(i, 1) Then
iCounter += 1
ReDim Preserve iReturn(iCounter)
iReturn(iCounter) = i
End If
Next i
Return iReturn
End Function
The function will return Nothing if there are no matching indices.
The functions only test for the length of StringA so it will throw an error if either StringB or StringC is shorter than String A. I inferred that the strings that you will be testing will be pre-validated as being all equal in length.

Extract char by sequence in a string vb 2010

I have a text in richtextbox1, I want to extract each 3 char of the string and so on, like:
richtextbox1.text = "It's Chrismas time"
Result, Sequence of 3 from Right to Left: "Isrmte"
Result, Sequence of 3 from Left to Right: "etmrsI"
How can I do it ?
Code can be in C# 2010. I will translate to vb.net 2010.

How about richtextbox1.text.Where((c, i) => i % 3 == 0)?
Or RTL: richtextbox1.text.Reverse().Where((c, i) => i % 3 == 0)
In VB: richtextbox1.text.Where(Function(c, i) i Mod 3 = 0)
However, your example does not show extracting every third character -- your example ignores whitespace, which you might do this way:
text.Where(Function(c) Not Char.IsWhiteSpace(c)).Where(Function(c, i) i Mod 3 = 0)
To take the text and put it into another textbox, you could do this:
textbox2.text = String.Join("", textbox1.text
.Where(Function(c) Not Char.IsWhiteSpace(c))
.Where(Function(c, i) i Mod 3 = 0))
Here's my test code copied directly from VS 2010:
Dim text = "It's Chrismas time"
Console.WriteLine(String.Join("",
text.Where(Function(c) Not Char.IsWhiteSpace(c)) _
.Where(Function(c, i) i Mod 3 = 0)))