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Get specific values of a struct/List

I'm creating a game in Unity3D + C#.
What I've got at the moment: an SQL datatable, consisting of 8 columns holding a total of 3 entries and a list "_WeapList" that holds every entry (as shown below).
public struct data
{
public string Name;
public int ID, dmg, range, magazin, startammo;
public float tbtwb, rltimer;
}
List<data> _WeapList;
public Dictionary<int, data>_WeapoList; //probable change
[...]
//reading the SQL Table + parse it into a new List-entry
while (rdr.Read())
{
data itm = new data();
itm.Name = rdr["Name"].ToString();
itm.ID = int.Parse (rdr["ID"].ToString());
itm.dmg = int.Parse (rdr["dmg"].ToString());
itm.range = int.Parse (rdr["range"].ToString());
itm.magazin = int.Parse (rdr["magazin"].ToString());
itm.startammo = int.Parse (rdr["startammo"].ToString());
itm.tbtwb = float.Parse(rdr["tbtwb"].ToString());
itm.rltimer = float.Parse(rdr["rltimer"].ToString());
_WeapList.Add(itm);
_WeapoList.Add(itm.ID, itm);//probable change
}
Now I want to create a "Weapon"-Class that will have the same 8 fields, feeding them via a given ID
How do I extract the values of a specific item (determined by the int ID, which is always unique) in the list/struct?
public class Weapons : MonoBehaviour
{
public string _Name;
public int _ID, _dmg, _range, _magazin, _startammo;
public float _tbtwb, _rltimer;
void Start()
{//Heres the main problem
_Name = _WeapoList...?
_dmg = _WeapoList...?
}
}

If your collection of weapons may become quite large or you need to frequently look up weapons in it, I would suggest using a Dictionary instead of a List for this (using the weapon ID as the key). A lookup will be much quicker using a Dictionary key than searching through a List using a loop or LINQ.
You can do this by modifying your code to do this as follows:
public Dictionary<int, data>_WeapList;
[...]
//reading the SQL Table + parse it into a new List-entry
while (rdr.Read())
{
data itm = new data();
itm.Name = rdr["Name"].ToString();
itm.ID = int.Parse (rdr["ID"].ToString());
itm.dmg = int.Parse (rdr["dmg"].ToString());
itm.range = int.Parse (rdr["range"].ToString());
itm.magazin = int.Parse (rdr["magazin"].ToString());
itm.startammo = int.Parse (rdr["startammo"].ToString());
itm.tbtwb = float.Parse(rdr["tbtwb"].ToString());
itm.rltimer = float.Parse(rdr["rltimer"].ToString());
_WeapList.Add(itm.ID, itm);//probable change
}
Then, to access elements on the list, just use the syntax:
_WeapList[weaponID].dmg; // To access the damage of the weapon with the given weaponID
Guarding against invalid IDs:
If there's a risk of the weaponID supplied not existing, you can use the .ContainsKey() method to check for it first before trying to access its members:
if (_WeapList.ContainsKey(weaponID))
{
// Retrieve the weapon and access its members
}
else
{
// Weapon doesn't exist, default behaviour
}
Alternatively, if you're comfortable using out arguments, you can use .TryGetValue() instead for validation - this is even quicker than calling .ContainsKey() separately:
data weaponData;
if (_WeapList.TryGetValue(weaponID, out weaponData))
{
// weaponData is now populated with the weapon and you can access members on it
}
else
{
// Weapon doesn't exist, default behaviour
}
Hope this helps! Let me know if you have any questions.

Let specificWeapon be a weapon to be searched in the list, then you can use the following code to select that item from the list of weapons, if it is not found then nullwill be returned. Hope that this what you are looking for:
var selectedWeapon = WeapList.FirstOrDefault(x=> x.ID == specificWeapon.ID);
if(selectedWeapon != null)
{
// this is your weapon proceed
}
else
{
// not found your weapon
}

You can use LINQ to search specific object through weaponId
var Weapon = _WeapList.FirstOrDefault(w=> w.ID == weaponId);

How to sort strings by a different value

I've tried looking for an existing question but wasn't sure how to phrase this and this retrieved no results anywhere :(
Anyway, I have a class of "Order Items" that has different properties. These order items are for clothing, so they will have a size (string).
Because I am OCD about these sorts of things, I would like to have the elements sorted not by the sizes as alphanumeric values, but by the sizes in a custom order.
I would also like to not have this custom order hard-coded if possible.
To break it down, if I have a list of these order items with a size in each one, like so:
2XL
S
5XL
M
With alphanumeric sorting it would be in this order:
2XL
5XL
M
S
But I would like to sort this list into this order (from smallest size to largest):
S
M
2XL
5XL
The only way I can think of to do this is to have a hard-coded array of the sizes and to sort by their index, then when I need to grab the size value I can grab the size order array[i] value. But, as I said, I would prefer this order not to be hard-coded.
The reason I would like the order to be dynamic is the order items are loaded from files on the hard disk at runtime, and also added/edited/deleted by the user at run-time, and they may contain a size that I haven't hard-coded, for example I could hard code all the way from 10XS to 10XL but if someone adds the size "110cm" (aka a Medium), it will turn up somewhere in the order that I don't want it to, assuming the program doesn't crash and burn.
I can't quite wrap my head around how to do this.

Also, you could create a Dictionary<int, string> and add Key as Ordering order below. Leaving some gaps between Keys to accomodate new sizes for the future. Ex: if you want to add L (Large), you could add a new item as {15, "L"} without breaking the current order.
Dictionary<int, string> mySizes = new Dictionary<int, string> {
{ 20, "2XL" }, { 1, "S" },
{ 30, "5XL" }, { 10, "M" }
};
var sizes = mySizes.OrderBy(s => s.Key)
.Select(s => new {Size = s.Value})
.ToList();

You can use OrderByDescending + ThenByDescending directly:
sizes.OrderByDescending(s => s == "S")
.ThenByDescending( s => s == "M")
.ThenByDescending( s => s == "2XL")
.ThenByDescending( s => s == "5XL")
.ThenBy(s => s);
I use ...Descending since a true is similar to 1 whereas a false is 0.

I would implement IComparer<string> into your own TShirtSizeComparer. You might have to do some regular expressions to get at the values you need.
IComparer<T> is a great interface for any sorting mechanism. A lot of built-in stuff in the .NET framework uses it. It makes the sorting reusable.
I would really suggest parsing the size string into a separate object that has the size number and the size size then sorting with that.

You need to implement the IComparer interface on your class. You can google how to do that as there are many examples out there

you'll have to make a simple parser for this. You can search inside the string for elements like XS XL and cm" if you then filter that out you have your unit. Then you can obtain the integer that is the value. If you have that you can indeed use an IComparer object but it doesn't have that much of an advantage.

I would make a class out of Size, it is likely that you will need to add more functionality to this in the future. I added the full name of the size, but you could also add variables like width and length, and converters for inches or cm.
private void LoadSizes()
{
List<Size> sizes = new List<Size>();
sizes.Add(new Size("2X-Large", "2XL", 3));
sizes.Add(new Size("Small", "S", 1));
sizes.Add(new Size("5X-Large", "5XL", 4));
sizes.Add(new Size("Medium", "M", 2));
List<string> sizesShortNameOrder = sizes.OrderBy(s => s.Order).Select(s => s.ShortName).ToList();
//If you want to use the size class:
//List<Size> sizesOrder = sizes.OrderBy(s => s.Order).ToList();
}
public class Size
{
private string _name;
private string _shortName;
private int _order;
public string Name
{
get { return _name; }
}
public string ShortName
{
get { return _shortName; }
}
public int Order
{
get { return _order; }
}
public Size(string name, string shortName, int order)
{
_name = name;
_shortName = shortName;
_order = order;
}
}

I implemented TShirtSizeComparer with base class Comparer<object>. Of course you have to adjust it to the sizes and objects you have available:
public class TShirtSizeComparer : Comparer<object>
{
// Compares TShirtSizes and orders them by size
public override int Compare(object x, object y)
{
var _sizesInOrder = new List<string> { "None", "XS", "S", "M", "L", "XL", "XXL", "XXXL", "110 cl", "120 cl", "130 cl", "140 cl", "150 cl" };
var indexX = -9999;
var indexY = -9999;
if (x is TShirt)
{
indexX = _sizesInOrder.IndexOf(((TShirt)x).Size);
indexY = _sizesInOrder.IndexOf(((TShirt)y).Size);
}
else if (x is TShirtListViewModel)
{
indexX = _sizesInOrder.IndexOf(((TShirtListViewModel)x).Size);
indexY = _sizesInOrder.IndexOf(((TShirtListViewModel)y).Size);
}
else if (x is MySelectItem)
{
indexX = _sizesInOrder.IndexOf(((MySelectItem)x).Value);
indexY = _sizesInOrder.IndexOf(((MySelectItem)y).Value);
}
if (indexX > -1 && indexY > -1)
{
return indexX.CompareTo(indexY);
}
else if (indexX > -1)
{
return -1;
}
else if (indexY > -1)
{
return 1;
}
else
{
return 0;
}
}
}
To use it you just have a List or whatever your object is and do:
tshirtList.Sort(new TShirtSizeComparer());
The order you have "hard-coded" is prioritized and the rest is put to the back.
I'm sure it can be done a bit smarter and more generalized to avoid hard-coding it all. You could e.g. look for sizes ending with an "S" and then check how many X's (e.g. XXS) or the number before X (e.g. 2XS) and sort by that, and then repeat for "L" and perhaps other "main sizes".

C# Struct instance behavior changes when captured in lambda

I've got a work around for this issue, but I'm trying to figure out why it works . Basically, I'm looping through a list of structs using foreach. If I include a LINQ statement that references the current struct before I call a method of the struct, the method is unable to modify the members of the struct. This happens regardless of whether the LINQ statement is even called. I was able to work around this by assigning the value I was looking for to a variable and using that in the LINQ, but I would like to know what is causing this. Here's an example I created.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace WeirdnessExample
{
public struct RawData
{
private int id;
public int ID
{
get{ return id;}
set { id = value; }
}
public void AssignID(int newID)
{
id = newID;
}
}
public class ProcessedData
{
public int ID { get; set; }
}
class Program
{
static void Main(string[] args)
{
List<ProcessedData> processedRecords = new List<ProcessedData>();
processedRecords.Add(new ProcessedData()
{
ID = 1
});
List<RawData> rawRecords = new List<RawData>();
rawRecords.Add(new RawData()
{
ID = 2
});
int i = 0;
foreach (RawData rawRec in rawRecords)
{
int id = rawRec.ID;
if (i < 0 || i > 20)
{
List<ProcessedData> matchingRecs = processedRecords.FindAll(mr => mr.ID == rawRec.ID);
}
Console.Write(String.Format("With LINQ: ID Before Assignment = {0}, ", rawRec.ID)); //2
rawRec.AssignID(id + 8);
Console.WriteLine(String.Format("ID After Assignment = {0}", rawRec.ID)); //2
i++;
}
rawRecords = new List<RawData>();
rawRecords.Add(new RawData()
{
ID = 2
});
i = 0;
foreach (RawData rawRec in rawRecords)
{
int id = rawRec.ID;
if (i < 0)
{
List<ProcessedData> matchingRecs = processedRecords.FindAll(mr => mr.ID == id);
}
Console.Write(String.Format("With LINQ: ID Before Assignment = {0}, ", rawRec.ID)); //2
rawRec.AssignID(id + 8);
Console.WriteLine(String.Format("ID After Assignment = {0}", rawRec.ID)); //10
i++;
}
Console.ReadLine();
}
}
}

Okay, I've managed to reproduce this with a rather simpler test program, as shown below, and I now understand it. Admittedly understanding it doesn't make me feel any less nauseous, but hey... Explanation after code.
using System;
using System.Collections.Generic;
struct MutableStruct
{
public int Value { get; set; }
public void AssignValue(int newValue)
{
Value = newValue;
}
}
class Test
{
static void Main()
{
var list = new List<MutableStruct>()
{
new MutableStruct { Value = 10 }
};
Console.WriteLine("Without loop variable capture");
foreach (MutableStruct item in list)
{
Console.WriteLine("Before: {0}", item.Value); // 10
item.AssignValue(30);
Console.WriteLine("After: {0}", item.Value); // 30
}
// Reset...
list[0] = new MutableStruct { Value = 10 };
Console.WriteLine("With loop variable capture");
foreach (MutableStruct item in list)
{
Action capture = () => Console.WriteLine(item.Value);
Console.WriteLine("Before: {0}", item.Value); // 10
item.AssignValue(30);
Console.WriteLine("After: {0}", item.Value); // Still 10!
}
}
}
The difference between the two loops is that in the second one, the loop variable is captured by a lambda expression. The second loop is effectively turned into something like this:
// Nested class, would actually have an unspeakable name
class CaptureHelper
{
public MutableStruct item;
public void Execute()
{
Console.WriteLine(item.Value);
}
}
...
// Second loop in main method
foreach (MutableStruct item in list)
{
CaptureHelper helper = new CaptureHelper();
helper.item = item;
Action capture = helper.Execute;
MutableStruct tmp = helper.item;
Console.WriteLine("Before: {0}", tmp.Value);
tmp = helper.item;
tmp.AssignValue(30);
tmp = helper.item;
Console.WriteLine("After: {0}", tmp.Value);
}
Now of course each time we copy the variable out of helper we get a fresh copy of the struct. This should normally be fine - the iteration variable is read-only, so we'd expect it not to change. However, you have a method which changes the contents of the struct, causing the unexpected behaviour.
Note that if you tried to change the property, you'd get a compile-time error:
Test.cs(37,13): error CS1654: Cannot modify members of 'item' because it is a
'foreach iteration variable'
Lessons:
Mutable structs are evil
Structs which are mutated by methods are doubly evil
Mutating a struct via a method call on an iteration variable which has been captured is triply evil to the extent of breakage
It's not 100% clear to me whether the C# compiler is behaving as per the spec here. I suspect it is. Even if it's not, I wouldn't want to suggest the team should put any effort into fixing it. Code like this is just begging to be broken in subtle ways.

Ok. We definitely have an issues here but I suspect that this issue not with closures per se but with foreach implementation instead.
C# 4.0 specification stated (8.8.4 The foreach statement) that "the iteration variable corresponds to a read-only local variable with a scope that extends over the embedded statement". That's why we can't change loop variable or increment it's property (as Jon already stated):
struct Mutable
{
public int X {get; set;}
public void ChangeX(int x) { X = x; }
}
var mutables = new List<Mutable>{new Mutable{ X = 1 }};
foreach(var item in mutables)
{
// Illegal!
item = new Mutable();
// Illegal as well!
item.X++;
}
In this regard read-only loop variables behave almost exactly the same as any readonly field (in terms of accessing this variable outside of the constructor):
We can't change readonly field outside of the constructor
We can't change property of the read-only field of value type
We're treating readonly fields as values that leads to using a temporary copy every time we accessing readonly field of value type.
.
class MutableReadonly
{
public readonly Mutable M = new Mutable {X = 1};
}
// Somewhere in the code
var mr = new MutableReadonly();
// Illegal!
mr.M = new Mutable();
// Illegal as well!
mr.M.X++;
// Legal but lead to undesired behavior
// becaues mr.M.X remains unchanged!
mr.M.ChangeX(10);
There is a plenty of issues related to mutable value types and one of them related to the last behavior: changing readonly struct via mutator method (like ChangeX) lead to obscure behavior because we'll modify a copy but not an readonly object itself:
mr.M.ChangeX(10);
Is equivalent to:
var tmp = mr.M;
tmp.ChangeX(10);
If loop variable treated by the C# compiler as a read-only local variable, than its seems reasonable to expect the same behavior for them as for read-only fields.
Right now loop variable in the simple loop (without any closures) behaves almost the same as a read-only field except copying it for every access. But if code changes and closure comes to play, loop variable starts behaving like pure read-only variable:
var mutables = new List<Mutable> { new Mutable { X = 1 } };
foreach (var m in mutables)
{
Console.WriteLine("Before change: {0}", m.X); // X = 1
// We'll change loop variable directly without temporary variable
m.ChangeX(10);
Console.WriteLine("After change: {0}", m.X); // X = 10
}
foreach (var m in mutables)
{
// We start treating m as a pure read-only variable!
Action a = () => Console.WriteLine(m.X));
Console.WriteLine("Before change: {0}", m.X); // X = 1
// We'll change a COPY instead of a m variable!
m.ChangeX(10);
Console.WriteLine("After change: {0}", m.X); // X = 1
}
Unfortunately I can't find strict rules how read-only local variables should behave but its clear that this behavior is different based on loop body: we're not copying to locals for every access in simple loop, but we DO this if the loop body closes over loop variable.
We all know that Closing over loop variable considered harmful and that loop implementation was changed in the C# 5.0. Simple way to fix that old issue in pre C# 5.0 era was introducing local variable, but interesting that introducing local variable in this our case will change behavior as well:
foreach (var mLoop in mutables)
{
// Introducing local variable!
var m = mLoop;
// We're capturing local variable instead of loop variable
Action a = () => Console.WriteLine(m.X));
Console.WriteLine("Before change: {0}", m.X); // X = 1
// We'll roll back this behavior and will change
// value type directly in the closure without making a copy!
m.ChangeX(10); // X = 10 !!
Console.WriteLine("After change: {0}", m.X); // X = 1
}
Actually this means that C# 5.0 has very subtle breaking change because no one will introduce a local variable any more (and even tools like ReSharper stops warning about it in VS2012 because its not an issue).
I'm OK with both behaviors but inconsistency seems strange.

I suspect this has to do with how lambda expressions are evaluated. See this question and its answer for more details.
Question:
When using lambda expressions or anonymous methods in C#, we have to be wary of the access to modified closure pitfall. For example:
foreach (var s in strings)
{
query = query.Where(i => i.Prop == s); // access to modified closure
Due to the modified closure, the above code will cause all of the Where clauses on the query to be based on the final value of s.
Answer:
This is one of the worst "gotchas" in C#, and we are going to take the breaking change to fix it. In C# 5 the foreach loop variable will be logically inside the body of the loop, and therefore closures will get a fresh copy every time.

Just to accomplish Sergey's post, I wanna to add following example with manual closure, that demonstrates compiler's behavior. Of course compiler might have any other implementation that satisfies readonly requirement of captured within foreach statement variable.
static void Main()
{
var list = new List<MutableStruct>()
{
new MutableStruct { Value = 10 }
};
foreach (MutableStruct item in list)
{
var c = new Closure(item);
Console.WriteLine(c.Item.Value);
Console.WriteLine("Before: {0}", c.Item.Value); // 10
c.Item.AssignValue(30);
Console.WriteLine("After: {0}", c.Item.Value); // Still 10!
}
}
class Closure
{
public Closure(MutableStruct item){
Item = item;
}
//readonly modifier is mandatory
public readonly MutableStruct Item;
public void Foo()
{
Console.WriteLine(Item.Value);
}
}

This might solve your issue. It swaps out foreach for a for and makes the struct immutable.
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace WeirdnessExample
{
public struct RawData
{
private readonly int id;
public int ID
{
get{ return id;}
}
public RawData(int newID)
{
id = newID;
}
}
public class ProcessedData
{
private readonly int id;
public int ID
{
get{ return id;}
}
public ProcessedData(int newID)
{
id = newID;
}
}
class Program
{
static void Main(string[] args)
{
List<ProcessedData> processedRecords = new List<ProcessedData>();
processedRecords.Add(new ProcessedData(1));
List<RawData> rawRecords = new List<RawData>();
rawRecords.Add(new RawData(2));
for (int i = 0; i < rawRecords.Count; i++)
{
RawData rawRec = rawRecords[i];
int id = rawRec.ID;
if (i < 0 || i > 20)
{
RawData rawRec2 = rawRec;
List<ProcessedData> matchingRecs = processedRecords.FindAll(mr => mr.ID == rawRec2.ID);
}
Console.Write(String.Format("With LINQ: ID Before Assignment = {0}, ", rawRec.ID)); //2
rawRec = new RawData(rawRec.ID + 8);
Console.WriteLine(String.Format("ID After Assignment = {0}", rawRec.ID)); //2
i++;
}
rawRecords = new List<RawData>();
rawRecords.Add(new RawData(2));
for (int i = 0; i < rawRecords.Count; i++)
{
RawData rawRec = rawRecords[i];
int id = rawRec.ID;
if (i < 0)
{
List<ProcessedData> matchingRecs = processedRecords.FindAll(mr => mr.ID == id);
}
Console.Write(String.Format("With LINQ: ID Before Assignment = {0}, ", rawRec.ID)); //2
rawRec = new RawData(rawRec.ID + 8);
Console.WriteLine(String.Format("ID After Assignment = {0}", rawRec.ID)); //10
i++;
}
Console.ReadLine();
}
}
}

Don't know how to loop through (n) number of nested objects in C#

I looked at this article to see if I could use that as a starting point, but I don't see it addressing my particular problem. C#: N For Loops
I have the following code:
int criteriaCount = rule.SearchCriteria.Criteria.Count();
string criteria = "";
for (int i = 0; i < criteriaCount; i++)
{
if (rule.SearchCriteria.Criteria[i].Criteria.Count() > 0)
{
criteria += string.Format("({0}" + System.Environment.NewLine, rule.SearchCriteria.Criteria[i].Display);
criteria += string.Format("{0})" + System.Environment.NewLine, rule.SearchCriteria.Criteria[i].Criteria[i].Display);
}
else
{
criteria += string.Format("[{0}]" + System.Environment.NewLine, rule.SearchCriteria.Criteria[i].Display);
}
}
To explain a little, you have in SearchCriteria and Array of Criteria[]. I can loop through this and grab the follow I need from each Criteria object as you can see I am doing.
I am also looking at the second level deep, so SearchCriteria.Criteria[n].Criteria[n] and I can put a for loop their and grab any nested values there as well.
The part I cannot figure out is how can I account for a variable number of nested Criteria objects? I could potentially have this:
SearchCriteria.Criteria[n].Criteria[n] ... (repeat a hundred times)... .Criteria[n]
So it can have potentially an infinite number of nested objects, and an infinite number of sibling objects (Criteria[0], Criteria[1] ... Criteria[100000] is what I mean).
Is there a way I can loop through all this? I have heard the a recursive loop may be the answer, and I vaguely understand that concept, but what I don't know is how can I get the number of children and siblings?

The basic concept for a recursive loop is defined below. You will be limited to the space available on the stack.
private String GetSearchCriteria(Citeria root) {
String result = root.Display;
foreach (Criteria child in root.Criteria) {
result += GetSearchCriteria(child);
}
return result;
}

Use recursion, and in your case you may use something like this...
private static string DisplayCriteria(Criteria criteriaObject)
{
string criteria = "";
foreach(Criteria c in criteriaObject)
{
if (c.Criteria.Count() > 0)
{
criteria += string.Format("({0}" + System.Environment.NewLine, c.Display);
criteria += string.Format("{0})" + System.Environment.NewLine, DisplayCriteria(c.Criteria));
}
else
{
criteria += string.Format("[{0}]" + System.Environment.NewLine, c.Display);
}
}
return criteria;
}
// your code ...
DisplayCriteria(rule.SearchCriteria.Criteria);
// your code ...
I am not sure about the new lines there, you can add/remove them later

You need to make your method into a "Recursive Method"...a method that calls itself to handle unlimited nesting, such as this:
public string ParseCriteria( Criteria criteria ) {
string result = "(";
result += criteria.Display;
foreach( var criteria in criteria.Criteria) {
result += ParseCriteria( criteria )
}
return result;
}
then, something like this in your existing code.
foreach( var criteria in rule.SearchCriteria.Criteria ) {
string result += ParseCriteria(criteria);
}
string concatentation is not ideal, and my exmaple doesn't format correctly...but hopefully you get the idea.

Dynamically Generate Codes in C#

I have a list of Enums like the following:
public enum Evaluation : int
{
//Section 1
S1_1_1 = 579,
S1_1_2 = 584,
S1_1_3 = 589,
S1_1_4 = 594,
S1_1_5 = 599,
S1_1_6 = 604,
//Section 2
S1_2_1 = 610,
S1_2_2 = 615,
S1_2_3 = 620,
S1_2_4 = 625,
S1_2_5 = 630,
};
I want to iterate each section and use the values dynamically
int S1Count = 6;
for (int i = 1; i <= S1Count; i++)
{
VoteCount += string.IsNullOrEmpty(this.GetEvaluationValue(FormID, Evaluation.S1_1_ + i)) ? 0 : 1;
}
How can I achieve that? Thanks.
Sorry, my mistake. I tried to get the value from the database by using enum values which are IDs and I have to calculate counts, average for each section.

You can use Enum.Parse to do what you want I think though I don't reccomend it.
To use enum.Parse you'd just need to do something like:
Enum.Parse(typeof(Evaluation), String.Format("S1_1_{0}",i));
This does point at you using some dodgy methodology though. As I said in comments above you would be better off with a data structure allowing you to have sections and their contents easily differentiated. You can do this with either custom classes or maybe just a dictionary of Lists of ints...
Dictionary<int, List<int>> SectionContents;
and use it like:
foreach(int id in SectionContents[sectionNumber])
{
VoteCount += string.IsNullOrEmpty(this.GetEvaluationValue(FormID, id)) ? 0 : 1;
}
(I don't vouch for what's in the foreach, I'm just demonstrating how a dictionary of a list of ints could work).
Creating the Dictionary is easy enough and doesn't require enums. And if this is database stuff could easily be generated through a database query to get the IDs and what sections they are in and then create the data structure.

This will do it
public class Program
{
public static void Main()
{
foreach (FieldInfo fInfo in typeof(Evaluation).GetFields(BindingFlags.Public | BindingFlags.Static))
{
Console.WriteLine("Evaluation." + fInfo.Name);
}
Console.ReadLine();
}
}