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C# Comparing if two lists have the same order of items (alphabetical)

I'm facing a huge problem with comparing two lists. I just made copy of my first list and I tried to sort it. The problem is, I want to compare my original list and sorted one to see if they have same alphabetical order. I hope I provided enough information for my problem.
Thanks in advance
public void VerifyDataPrijave(string username)
{
List<string> listaTekstova = new List<string>(); //initializing new, empty List
var kartice = Repo.Kartice.CreateAdapter<Unknown>(false).Find(".//div[class='_63fz removableItem _95l5']");
foreach (var kartica in kartice) {
var slika = kartica.Find(".//tag[tagname='img']")[0];
var ime = slika.Find("following-sibling::div")[0];
string text = ime.GetAttributeValue("InnerText").ToString(); //loop through profile cards and getting Names as InnerText in variable text
listaTekstova.Add(text); //adding those "texts" I just found to an empty list initialized before
List<string> novaListaTekstova = new List<string>(listaTekstova); //clone (copy) of the very first one list
novaListaTekstova.Sort(); //sorting that list alphabetically (I suppose, not sure)
}
}

You can use SequenceEqual to compare to IEnumerables. In your case you can do something like this once all sorting has been done:
var isEqual = novaListaTekstova.SequenceEqual(listaTekstova);

How do I remove duplicates from excel range? c#

I've converted cells in my excel range from strings to form a string list and have separated each item after the comma in the original list. I am starting to think I have not actually separated each item, and they are still one whole, trying to figure out how to do this properly so that each item( ie. the_red_bucket_01)is it's own string.
example of original string in a cell 1 and 2:
Cell1 :
the_red_bucket_01, the_blue_duck_01,_the green_banana_02, the orange_bear_01
Cell2 :
the_purple_chair_01, the_blue_coyote_01,_the green_banana_02, the orange_bear_01
The new list looks like this, though I'm not sure they are separate items:
the_red_bucket_01
the_blue_duck_01
the green_banana_02
the orange_bear_01
the_red_chair_01
the_blue_coyote_01
the green_banana_02
the orange_bear_01
Now I want to remove duplicates so that the console only shows 1 of each item, no matter how many there are of them, I can't seem to get my foreah/if statements to work. It is printing out multiple copies of the items, I'm assuming because it is iterating for each item in the list, so it is returning the data that many items.
foreach (Excel.Range item in xlRng)
{
string itemString = (string)item.Text;
List<String> fn = new List<String>(itemString.Split(','));
List<string> newList = new List<string>();
foreach (string s in fn)
if (!newList.Contains(s))
{
newList.Add(s);
}
foreach (string combo in newList)
{
Console.Write(combo);
}

You probably need to trim the strings, because they have leading white spaces, so "string1" is different from " string1".
foreach (string s in fn)
if (!newList.Contains(s.Trim()))
{
newList.Add(s);
}

You can do this much simpler with Linq by using Distinct.
Returns distinct elements from a sequence by using the default
equality comparer to compare values.
foreach (Excel.Range item in xlRng)
{
string itemString = (string)item.Text;
List<String> fn = new List<String>(itemString.Split(','));
foreach (string combo in fn.Distinct())
{
Console.Write(combo);
}
}
As mentioned in another answer, you may also need to Trim any whitespace, in which case you would do:
fn.Select(x => x.Trim()).Distinct()

Where you need to contain keys/values, its better to use Dictionary type. Try changing code with List<T> to Dictionary<T>. i.e.
From:
List<string> newList = new List<string>();
foreach (string s in fn)
if (!newList.Containss))
{
newList.Add(s);
}
to
Dictionary<string, string> newList = new Dictionary<string, string>();
foreach (string s in fn)
if (!newList.ContainsKey(s))
{
newList.Add(s, s);
}

If you are concerned about the distinct items while you are reading, then just use the Distinct operator like fn.Distinct()
For processing the whole data, I can suggest two methods:
Read in the whole data then use LINQ's Distinct operator
Or use a Set data structure and store each element in that while reading the excel
I suggest that you take a look at the LINQ documentation if you are processing data. It has really great extensions. For even more methods, you can check out the MoreLINQ package.

I think your code would probably work as you expect if you moved newList out of the loop - you create a new variable named newList each loop so it's not going to find duplicates from earlier loops.
You can do all of this this more concisely with Linq:
//set up some similar data
string list1 = "a,b,c,d,a,f";
string list2 = "a,b,c,d,a,f";
List<string> lists = new List<string> {list1,list2};
// find unique items
var result = lists.SelectMany(i=>i.Split(',')).Distinct().ToList();
SelectMany() "flattens" the list of lists into a list.
Distinct() removes duplicates.

var uniqueItems = new HashSet<string>();
foreach (Excel.Range cell in xlRng)
{
var cellText = (string)cell.Text;
foreach (var item in cellText.Split(',').Select(s => s.Trim()))
{
uniqueItems.Add(item);
}
}
foreach (var item in uniqueItems)
{
Console.WriteLine(item);
}

How to append a string in front of all elements in any List<string> in C#

Is there any way I can insert a prefix string "/directory/" in front of all elements in the list ["file1.json", "file2.json"]?
Result I'm looking for would be ["/directory/file1.json", "/directory/file2.json"].

You could use the linq extension method: Select()
List<string> myList = new List<string> { "file1.JSON", "file2.JSON" };
var directory = "/directory";
myList = myList.Select(filename => Path.Combine(directory, filename)).ToList();
This will execute the Path.Combine(directory, filename) foreach item in the list. I'm using the Path.Combine method, because thats the best way to concat directories/filenames, because it should be platform independend.

Try this :
List<string> yourlist = new List<string> { "file1.JSON", "file2.JSON" };
var directory = "/directory/";
yourlist = yourlist.Select(f => string.Concat(directory,f)).ToList();

All the answers using Select are actually creating a new list if you really want to change the values in the existing list then just use a for loop
for(int i = 0; i < fileList.Count; i++)
fileList[i] = #"/directory/" + fileList[i];

You can use the extension method Enumerable.Select. There are two ways of calling Select:
Method syntax
var originalList = new List<string> { "file1.json", "file2.json" };
var list = originalList.Select(e => "/directory/" + e);
Query syntax
var originalList = new List<string> { "file1.json", "file2.json" };
var list = from e in originalList select "/directory/" + e;
Both are the same.

You can use like the following, Which will give you a List as per your requirement:
string stringToappend=#"/Directory/";
List<string> JsonList= new List<string> (){"file1.JSON","file2.JSON"};
var AppendedLis=JsonList.Select(x=> Path.Combine(stringToappend, x)).ToList();
Note :- The LINQ Extension method .Select help you to do this operation, Which will internally iterate through each element in the collection and append the required string with each item and Gives you the List as per your requirements

QuickSort void problems

I've been trying to write my own quicksort in C#.
However, when I concatenate the lower, pivot and greater partitions, Visual Studio tells me it cant convert void to string list, though I'm not sure how the concatenated lessList and moreList even becomes void.
Code snippet:
public List<string> SortFiles(List<string> fileList)
{
int listSize = fileList.Count;
if (listSize <= 1)
{
return fileList; //because it is already sorted
}
string pivotString = fileList[listSize/2];
//partition list
List<string> lessList = new List<string>();
List<string> moreList = new List<string>();
foreach (string g in fileList)
{
if (String.Compare(g, pivotString) <= 0)
{
lessList.Add(g);
}
else
{
moreList.Add(g);
}
}
lessList = SortFiles(lessList);
moreList = SortFiles(moreList);
//concatenate lessList + pivot + moreList
List<string> sortedFiles = lessList.Add(pivotString); //thinks is void
sortedFiles = sortedFiles.AddRange(moreList); //thinks is void
return sortedFiles;

The fact is that Add and AddRange don't return a new list with the added element (or range).
Rather, they add the element(s) to the list, modifying it in-place.
In fact you can simply modify the code to just do the Add and AddRange, and it will work.
Note though that it will be rather inefficient, as you are creating lists and copying thing around a lot.

how to dissect string values

How can I dissect or retrieve string values?
Here's the sample code that I'm working on now:
private void SplitStrings()
{
List<string> listvalues = new List<string>();
listvalues = (List<string>)Session["mylist"];
string[] strvalues = listvalues.ToArray();
for (int x = 0; x < strvalues.Length; x++)
{
}
}
Now that I'am able to retrieve list values in my session. How can I separately get the values of each list using foreach or for statement?
What I want to happen is to programmatically split the values of the strings depending on how many is in the list.

If you have a list of string values, you can do the following:
private void SplitStrings()
{
List<string> listValues = (List<string>) Session["mylist"];
// always check session values for null
if(listValues != null)
{
// go through each list item
foreach(string stringElement in listValues)
{
// do something with variable 'stringElement'
System.Console.WriteLine(stringElement);
}
}
}
Note that I test the result of casting the session and that I don't create a new list first-off, which is not necessary. Also note that I don't convert to an array, simply because looping a list is actually easier, or just as easy, as looping an array.
Note that you named your method SplitStrings, but we're not splitting anything. Did you mean to split something like "one;two;three;four" in a four-element list, based on the separator character?

I'm not sure what you're trying to obtain in this code, I don't know why you're converting your List to an Array.
You can loop through your listValues collection with a foreach block:
foreach(string value in listValues)
{
//do something with value, I.e.
Response.Write(value);
}

I don't know what's in the strings but you can start by simplifying. There is no point allocating a new List if you're going to overwrite it immediately.
private void SplitStrings()
{
List<string> list = (List<string>)Session["mylist"];
foreach(string value in list)
{
}
}

List listvalues = (List)Session["mylist"];
foreach (string s in listvalues)
{
//do what you want with s here
}