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C# convert dictionary into CSV like string

I have a dictionary Dictionary<string, List<string>> I want order it alphabetically by the keys and convert it into a string that can be written into a CSV file with the keys as column headers and the values as values for that column.
My onordered dictionary looks like:
{
"Name" : ["John", "Ciara", "Moses"],
"Age" : ["23", "16", "37"],
"State" : ["Alabama", "Florida", "New York"]
}
The end result will look like:
Age,Name,State
23,John,Alabama
16,Ciara,Florida
37,Moses,New York
Please how I can achieve this in C#?
For clarity, here is a link to what the task entail.
And below is my approach of solving it. I converted the string into a dictionary with the column headings as keys. My problem now is converting the dictionary back to the string format.
public static string SortCsvColumns( string csv_data )
{
var data = csv_data.Split(new string[] { Environment.NewLine }, StringSplitOptions.None);
var values = data.Skip(1).ToArray();
var splittedValues = new List<List<string>>();
var dataSet = data[0].Split(new string[] {","}, StringSplitOptions.None).ToDictionary(x => x, x => new List<string>());
for(int i = 0; i < values.Length; i++)
{
splittedValues.Add(values[i].Split(new string[] { "," }, StringSplitOptions.None).ToList());
}
for(int i = 0; i < splittedValues.Count(); i++) {
var splittedValue = splittedValues[i];
for(int j = 0; j < splittedValue.Count(); j++) {
dataSet.Values.ElementAt(i).Add(splittedValue[j]);
}
}
dataSet = dataSet.OrderBy(key => key.Key);
}
Can someone suggest the best approach to do this please.

First, create a map to re-order the columns in sorted order by column header:
var map = new StringReader(csv_data).ReadLine() // get header line
.Split(';') // split into array of headers
.Select((h, n) => new { header = h, OrigPos = n }) // remember original position
.OrderBy(hn => hn.header, StringComparer.CurrentCultureIgnoreCase) // sort into new position
.Select(hn => hn.OrigPos) // return just old position new new order
.ToList();
Then remap each CSV line into the new order and recombine into a string:
using var sr = new StringReader(csv_data);
var ans = String.Join("\n",
sr.ReadLines()
.Select(line => line.Split(';'))
.Select(columns => String.Join(";", map.Select(pos => columns[pos]))));
This requires an extension method on TextReader to enumerate the lines of a TextReader:
public static class StringReaderExt {
public static IEnumerable<string> ReadLines(this TextReader sr) {
string line;
while ((line = sr.ReadLine()) != null)
yield return line;
}
}

Rename List item when there is the same string multiple time

I have List of names like:
var list = new List<string> {"Allan", "Michael", "Jhon", "Smith", "George", "Jhon"};
and a combobox which itemssource is my list. As you can see in the list there is Jhon 2 times, what I want is when I put those name into combobox add "2" to second Jhon. I mean when I open the combobox names in it shoud look like:
Allan
Michael
Jhon
Smith
George
Jhon2
I have tired linq to do that but I'm quite new to c#/linq. Could someone show me simple way to do that?

I would do this:
var result = list.Take(1).ToList();
for (var i = 1; i < list.Count; i++)
{
var name = list[i];
var count = list.Take(i - 1).Where(n => n == name).Count() + 1;
result.Add(count < 2 ? name : name + count.ToString());
}

Here is what I would do:
First off, separate the list into two smaller ones, one that contains all the unique names, and one that contains only duplicates:
var duplicates = myList.GroupBy(s => s)
.SelectMany(grp => grp.Skip(1));
var unique = new HashSet<string>(myList).ToList();
Then process:
var result = new List<string>();
foreach (string uniqueName in unique)
{
int index=2;
foreach (string duplicateName in duplicates.Where(dupe => dupe == uniqueName))
{
result.Add(string.Format("{0}{1}", duplicateName, index.ToString()));
index++;
}
}
What we are doing here is the following:
Iterate through unique names.
Initialize a variable index with value 2. This will be the number we add at the end of each name.
Iterate through matching duplicate names.
Modify the name string by adding the number stored at index to the end.
Add this new value to the results list.
Increment index.
Finally, add the unique names back in:
result.AddRange(unique);
The result list should now contain all the same values as the original myList, only difference being that all names that appear more than once have a number appended to their end. Per your specification, there is no name name1. Instead, counting starts from 2.

Another possibility:
var groups = list.Select((name, index) => new { name, index }).GroupBy(s => s.name).ToList();
foreach (var group in groups.Where(g => g.Count() > 1))
{
foreach (var entry in group.Skip(1).Select((g, i) => new { g, i }))
{
list[entry.g.index] = list[entry.g.index] + entry.i;
}
}

Someone might be able to give a more efficient answer, but this does the job.
The dictionary keeps track of how many times a name has been repeated in the list. Each time a new name in the list is encountered, it is added to the dictionary and is added as is to the new list. If the name already exists in the dictionary (with the key check), instead, the count is increased by one in the dictionary and this name is added to the new list with the count (from the dictionary value corresponding to the name as the key) appended to the end of the name.
var list = new List<string> {"Allan", "Michael", "Jhon", "Smith", "George", "Jhon", "George", "George"};
Dictionary<string, int> dictionary = new Dictionary<string,int>();
var newList = new List<string>();
for(int i=0; i<list.Count();i++){
if(!dictionary.ContainsKey(list[i])){
dictionary.Add(list[i], 1);
newList.Add(list[i]);
}
else{
dictionary[list[i]] += 1;
newList.Add(list[i] + dictionary[list[i]]);
}
}
for(int i=0; i<newList.Count(); i++){
Console.WriteLine(newList[i]);
}
Output:
Allan
Michael
Jhon
Smith
George
Jhon2
George2
George3

Check this solution:
public List<string> AddName(IEnumerable<string> list, string name)
{
var suffixSelector = new Regex("^(?<name>[A-Za-z]+)(?<suffix>\\d?)$",
RegexOptions.Singleline);
var namesMap = list.Select(n => suffixSelector.Match(n))
.Select(x => new {name = x.Groups["name"].Value, suffix = x.Groups["suffix"].Value})
.GroupBy(x => x.name)
.ToDictionary(x => x.Key, x => x.Count());
if (namesMap.ContainsKey(name))
namesMap[name] = namesMap[name] + 1;
return namesMap.Select(x => x.Key).Concat(
namesMap.Where(x => x.Value > 1)
.SelectMany(x => Enumerable.Range(2, x.Value - 1)
.Select(i => $"{x.Key}{i}"))).ToList();
}
It handle case when you already has 'Jhon2' in the list

I would do
class Program
{
private static void Main(string[] args)
{
var list = new List<string> { "Allan", "Michael", "Jhon", "Smith", "George", "Jhon" };
var duplicates = list.GroupBy(x => x).Select(r => GetTuple(r.Key, r.Count()))
.Where(x => x.Count > 1)
.Select(c => { c.Count = 1; return c; }).ToList();
var result = list.Select(v =>
{
var val = duplicates.FirstOrDefault(x => x.Name == v);
if (val != null)
{
if (val.Count != 1)
{
v = v + " " + val.Count;
}
val.Count += 1;
}
return v;
}).ToList();
Console.ReadLine();
}
private static FooBar GetTuple(string key, int count)
{
return new FooBar(key, count);
}
}
public class FooBar
{
public int Count { get; set; }
public string Name { get; set; }
public FooBar(string name, int count)
{
Count = count;
Name = name;
}
}

Can I store LINQ query result in an array?

This is the code using LINQ, it stores the values into list
string StringRegex = "\"(?:[^\"\\\\]|\\\\.)*\"";
Dictionary<string, string> dictionaryofString = new Dictionary<string, string>()
{
{"String", StringRegex}
};
var matches = dictionaryofString.SelectMany(a => Regex.Matches(input,a.Value)
.Cast<Match>()
.Select(b =>
new
{
Index = b.Index,
Value = b.Value,
Token = a.Key
}))
.OrderBy(a => a.Index).ToList();
for (int i = 0; i < matches.Count; i++)
{
if (i + 1 < matches.Count)
{
int firstEndPos = (matches[i].Index + matches[i].Value.Length);
if (firstEndPos > matches[(i + 1)].Index)
{
matches.RemoveAt(i + 1);
i--;
}
}
}
foreach (var match in matches)
{
Console.WriteLine(match);
}
Can it not be stored into Array? Where I can display only item I want. Just like here the output is {Index=, Value=, Token=}
Meanwhile I want the output that be of just "Value" "Token" index not needed.

You can use ToArray instead. But List gives you the desired array functionality already, you can access an item by its index.
var exampleQuery = select c from componentsDemo;
var list = exampleQuery.ToList();
var secondElement = list[1]; // <- demo only, there could be an exception thrown, if there's less than two elements in the list
EDIT: as I can see from your comments, you need this:
foreach (var match in matches)
{
Console.WriteLine(match.Value + ", " + match.Token);
}

how to arrange the item of a list into series arrangement

I have a list of data which contains of random data with combination of string and number:
List<String> Data1 = new List<String>()
{
"1001A",
"1002A",
"1003A",
"1004A",
"1015A",
"1016A",
"1007A",
"1008A",
"1009A",
};
I want this data to arrange into series like this:
1001A - 1004A, 1007A - 1009A, 1015A, 1016A
for every more than 2 counts of data series the output shall be have "-" between the first count and the last count of series, the other non series data will be just added to the last part and all together will separated by ",".
I'd already made some codes only to arrange the data series by the last char of it:
string get_REVISIONMARK = "A";
var raw_serries = arrange_REVISIONSERIES.Where(p => p[p.Length - 1].ToString() == get_REVISIONMARK) .OrderBy(p => p[p.Length - 1) .ThenBy(p => p.Substring(0, p.Length - 1)).ToList();
just ignore the last char I'd already have function for that, and my problem only about the arrangement of the numbers, the length of data is not fixed. for other example of output "1001A - 1005A, 301A, 32A"
I had another sample of my codes this works fine to me, but for me its so lazy code.
for (int c1 = 0; c1 < list_num.Count; c1++)
{
if (list_num[c1] != 0)
{
check1 = list_num[c1];
for (int c2 = 0; c2 < list_num.Count; c2++)
{
if (check1 == list_num[c2])
{
list_num[c2] = 0;
check1 += 1;
list_series.Add(arrange_REVISIONSERIES[c2]);
}
}
check1 = 0;
if (list_series.Count > 2)
{
res_series.Add(list_series[0] + " to " +list_series[list_series.Count - 1]);
list_series.Clear();
}
else
{
if (list_series.Count == 1)
{
res_series.Add(list_series[0]);
list_series.Clear();
}
else
{
res_series.Add(list_series[0] + "," + list_series[1]);
list_series.Clear();
}
}
}
}
var combine_res = String.Join(",", res_series);
MessageBox.Show(combine_res);
this codes work fine for the series number ...

A possible solution (working with current set of values), Please follow the steps below
Declare a class level string list as
public List<String> data_result = new List<string>();
Create a function to iterate through input string list (input string declared inside, named 'data')
public void ArrangeList()
{
List<String> data = new List<string>() { "1001A", "1002A", "1003A",
"1004A", "1015A", "1016A", "1007A", "1008A", "1009A", "1017A" };
List<int> data_int = data.Select(a => Convert.ToInt32(a.Substring(0,
a.Length - 1))).OrderBy(b => b).ToList();
int initializer = 0, counter = 0;
int finalizer = 0;
foreach (var item in data_int)
{
if (initializer == 0)
{ initializer = item; continue; }
else
{
counter++;
if (item == initializer + counter)
finalizer = item;
else
{
LogListing(initializer, finalizer);
initializer = item;
finalizer = item;
counter = 0;
}
}
}
LogListing(initializer, finalizer);
}
Create a function which just logs the result into data_result string list.
public void LogListing(int initializer, int finalizer)
{
if (initializer != finalizer)
{
if (finalizer == initializer + 1)
{
data_result.Add(initializer + "A");
data_result.Add(finalizer + "A");
}
else
data_result.Add(initializer + "A - " + finalizer + "A");
}
else
data_result.Add(initializer + "A");
}
It perfectly generates the result list as
Thumb-up if you like

A linqy solution:
char get_REVISIONMARK = 'A';
var res = arrange_REVISIONSERIES.Select(s => new { Rev = s[s.Length - 1], Value = int.Parse(s.Substring(0, s.Length - 1)), Org = s })
.Where(d => d.Rev == get_REVISIONMARK).OrderBy(d => d.Value)
.Select((val, ind) => new { Index = ind, Org = val.Org, Value = val.Value }).GroupBy(a => a.Value - a.Index)
.Select(gr=>gr.ToList()).OrderBy(l=>l.Count > 2 ? 0 : 1 ).Aggregate(new List<string>(), (list, sublist) =>
{
if (sublist.Count > 2)
list.Add(sublist[0].Org + " - " + sublist[sublist.Count - 1].Org);
else
list.AddRange(sublist.Select(a => a.Org));
return list;
});
The first lines are basically the same as the code you already have (filter on revision and sort), but with the difference that the subvalues are stored in an anonymous type. You could do the same on the pre ordered list, but since splitting the string would be done twice I've included it in the total.
Then a select with index (.Select((val, ind) =>) is made to get value/index pairs. This is done to be able to get the sequences based on an old t-sql row_number trick: for each 'group' the difference between value and index is the same .GroupBy(a => a.Value - a.Index)
After that, normally you'd be as good as done, but since you only want to make sequences of 2 and longer, we make sublists out of the groupby values and do the ordering beforehand to make sure the ranges come for the eventual single elements .Select(gr=>gr.ToList()).OrderBy(l=>l.Count > 2 ? 0 : 1 )
Finally, the list is created of the groups. Several options, but I like to use Aggregate for that. The seed is the resulting list, and the aggregate simply adds to that (where subranges > 2 are cummulated and for single elements and pairs, the single elements are added)

I'm making two assumptions:
The list is already ordered
The non-numeric characters can be ignored
You will get the results in the results variable:
void Main()
{
List<String> Data1 = new List<String>()
{
"1001A",
"1002A",
"1003A",
"1004A",
"1015A",
"1016A",
"1007A",
"1008A",
"1009A",
};
var accu = new List<List<Tuple<int, string>>>();
foreach (var data in Data1)
{
if (accu.Any(t => t.Any(d => d.Item1 == (ToInt(data) - 1))))
{
var item = accu.First(t => t.Any(d => d.Item1 == (ToInt(data) - 1)));
item.Add(new Tuple<int, string>(ToInt(data), data));
}
else
{
accu.Add(new List<Tuple<int, string>>{ new Tuple <int, string>(ToInt(data), data)});
}
}
var results = new List<string>();
results.AddRange(accu.Where(g => g.Count > 2).Select(g => string.Format("{0} - {1}", g.First().Item2, g.Last().Item2)));
results.AddRange(accu.Where(g => g.Count <= 2).Aggregate(new List<string>(), (total, current) => { total.AddRange(current.Select(i => i.Item2)); return total; } ));
}
private static Regex digitsOnly = new Regex(#"[^\d]");
public static int ToInt(string literal)
{
int i;
int.TryParse(digitsOnly.Replace(literal, ""), out i);
return i;
}

So given your starting data:
List<String> arrange_REVISIONSERIES = new List<String>()
{
"1001A",
"1002A",
"1003A",
"1004A",
"1015A",
"1016A",
"1007A",
"1008A",
"1009A",
};
I do this first:
var splits =
arrange_REVISIONSERIES
.Select(datum => new
{
value = int.Parse(datum.Substring(0, datum.Length - 1)),
suffix = datum.Substring(datum.Length - 1, 1),
})
.OrderBy(split => split.suffix)
.ThenBy(split => split.value)
.ToArray();
That's basically the same as your raw_serries, but orders the number part as a number. It seems to me that you need it as a number to make the range part work.
I then do this to compute the groupings:
var results =
splits
.Skip(1)
.Aggregate(
new[]
{
new
{
start = splits[0].value,
end = splits[0].value,
suffix = splits[0].suffix
}
}.ToList(),
(a, s) =>
{
if (a.Last().suffix == s.suffix && a.Last().end + 1 == s.value)
{
a[a.Count - 1] = new
{
start = a.Last().start,
end = s.value,
suffix = s.suffix
};
}
else
{
a.Add(new
{
start = s.value,
end = s.value,
suffix = s.suffix
});
}
return a;
})
.Select(r => r.start == r.end
? String.Format("{0}{1}", r.end, r.suffix)
: (r.start + 1 == r.end
? String.Format("{0}{2}, {1}{2}", r.start, r.end, r.suffix)
: String.Format("{0}{2} - {1}{2}", r.start, r.end, r.suffix)))
.ToArray();
And finally, this to create a single string:
var result = String.Join(", ", results);
That gives me:
1001A - 1004A, 1007A - 1009A, 1015A, 1016A
This code nicely works with data containing different suffixes.

c# array help on sorting

First of all sorry for my mistakes in English its not my primary language
i have a problem , i have a array like following
string[] arr1 = new string[] {
"Pakistan:4,India:3,USA:2,Iran:1,UK:0",
"Pakistan:4,India:3,USA:2,Iran:1,UK:0",
"India:4,USA:3,Iran:2,UK:1,Pakistan:0"
};
now i just want to know that how many times Pakistan comes with 1 ,
how many times with 2 , 3 , 4
and i need to know this about all India , USA , Iran , UK
Thanks in advance , you guys are my last hope .

This linq will convert the array into a Dictionary>, where the outer dictionary contains the countries names, and inner dictionaries will contain the ocurrence number (the number after ':') and the count for each ocurrence.
string[] arr1 = new string[]
{
"Pakistan:4,India:3,USA:2,Iran:1,UK:0",
"Pakistan:4,India:3,USA:2,Iran:1,UK:0",
"India:4,USA:3,Iran:2,UK:1,Pakistan:0"
};
var count = arr1
.SelectMany(s => s.Split(new[] { ',' }, StringSplitOptions.RemoveEmptyEntries))
.GroupBy(s => s.Split(':')[0], s => s.Split(':')[1])
.ToDictionary(g => g.Key,
g =>
{
var items = g.Distinct();
var result = new Dictionary<String, int>();
foreach (var item in items)
result[item] = g.Count(gitem => gitem == item);
return result;
});
// print the result
foreach(var country in count.Keys)
{
foreach(var ocurrence in count[country].Keys)
{
Console.WriteLine("{0} : {1} = {2}", country, ocurrence, count[country][ocurrence]);
}
}

I would use the String.Split(char[]) method and the String.SubString(int, int) method to inspect every 'country' inside your array and to get the number postfix of each country.
Try the following:
(The following code is now compiled and tested.)
Use a simple data structure to facilitate the task of holding the result of your operation.
public struct Result {
string Country { get; set; }
int Number { get; set; }
int Occurrences { get; set; }
}
// define what countries you are dealing with
string[] countries = new string[] { "Pakistan", "India", "USA", "Iran", "UK", }
Method to provide the overall result:
public static Result[] IterateOverAllCountries () {
// range of numbers forming the postfix of your country strings
int numbersToLookFor = 4;
// provide an array that stores all the local results
// numbersToLookFor + 1 to respect that numbers are starting with 0
Result[] result = new Result[countries.Length * (numbersToLookFor + 1)];
string currentCountry;
int c = 0;
// iterate over all countries
for (int i = 0; i < countries.Length; i++) {
currentCountry = countries[i];
int j = 0;
// do that for every number beginning with 0
// (according to your question)
int localResult;
while (j <= numbersToLookFor) {
localResult = FindCountryPosition(currentCountry, j);
// add another result to the array of all results
result[c] = new Result() { Country = currentCountry, Number = j, Occurrences = localResult };
j++;
c++;
}
}
return result;
}
Method to provide a local result:
// iterate over the whole array and search the
// occurrences of one particular country with one postfix number
public static int FindCountryPosition (string country, int number) {
int result = 0;
string[] subArray;
for (int i = 0; i < arr1.Length; i++) {
subArray = arr1[i].Split(',');
string current;
for (int j = 0; j < subArray.Length; j++) {
current = subArray[j];
if (
current.Equals(country + ":" + number) &&
current.Substring(current.Length - 1, 1).Equals(number + "")
)
result++;
}
}
return result;
}
The following should enable you to run the algorithm
// define what countries you are dealing with
static string[] countries = new string[] { "Pakistan", "India", "USA", "Iran", "UK", };
static string[] arr1 = new string[] {
"Pakistan:4,India:3,USA:2,Iran:1,UK:0",
"Pakistan:4,India:3,USA:2,Iran:1,UK:0",
"India:4,USA:3,Iran:2,UK:1,Pakistan:0"
};
static void Main (string[] args) {
Result[] r = IterateOverAllCountries();
}

The data structure you are using is not rich enough to provide you with that information. Hence you need to parse your string and create a new data structure to be able to provide (sring[][]):
string[] arr1 = new string[] {
"Pakistan,India,USA,Iran,UK",
"Pakistan,India,USA,Iran,UK",
"India,USA,Iran,UK,Pakistan"
};
string[][] richerArray = arr1.Select(x=> x.Split('\'')).ToArray();
var countPakistanIsFirst = richerArray.Select(x=>x[0] == "Pakistan").Count();
UPDATE
You seem to have changed your question. The answer applies to the original question.