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creating array of bad names to check and replace in c#

I'm looking to create a method that loops through an list and replaces with matched values with a new value. I have something working below but it really doesnt follow the DRY principal and looks ugly.
How could I create a dictionary of value pairs that would hold my data of values to match and replace?
var match = acreData.data;
foreach(var i in match)
{
if (i.county_name == "DE KALB")
{
i.county_name = "DEKALB";
}
if (i.county_name == "DU PAGE")
{
i.county_name = "DUPAGE";
}
}

In your question, you can try to use linq and Replace to make it.
var match = acreData.data.ToList();
match.ForEach(x =>
x.county_name = x.county_name.Replace(" ", "")
);
or you can try to create a mapper table to let your data mapper with your value. as #user2864740 say.
Dictionary<string, string> dict = new Dictionary<string, string>();
dict.Add("DE KALB", "DEKALB");
dict.Add("DU PAGE", "DUPAGE");
var match = acreData.data;
string val = string.Empty;
foreach (var i in match)
{
if (dict.TryGetValue(i.county_name, out val))
i.county_name = val;
}

If this were my problem and it is possible a county could have more than one common misspelling I would create a class to hold the correct name and the common misspellings. The you could easily determine if the misspelling exists and correct if. Something like this:
public class County
{
public string CountyName { get; set; }
public List<string> CommonMisspellings { get; set; }
public County()
{
CommonMisspellings = new List<string>();
}
}
Usage:
//most likely populate from db
var counties = new List<County>();
var dekalb = new County { CountyName = "DEKALB" };
dekalb.CommonMisspellings.Add("DE KALB");
dekalb.CommonMisspellings.Add("DE_KALB");
var test = "DE KALB";
if (counties.Any(c => c.CommonMisspellings.Contains(test)))
{
test = counties.First(c => c.CommonMisspellings.Contains(test)).CountyName;
}

If you are simply replacing all words in a list containing space without space, then can use below:
var newList = match.ConvertAll(word => word.Replace(" ", ""));
ConvertAll returns a new list.
Also, I suggest not to use variable names like i, j, k etc..but use temp etc.
Sample code below:
var oldList = new List<string> {"DE KALB", "DE PAGE"};
var newList = oldList.ConvertAll(word => word.Replace(" ", ""));

We can try removing all the characters but letters and apostroph (Cote d'Ivoire has it)
...
i.country_name = String.Concat(i.country_name
.Where(c => char.IsLetter(c) || c == '\''));
...

I made a comment under answer of #Kevin and it seems it needs further explanation. Sequential searching in list does not scale well and unfortunately for Kevin, that is not my opinion, asymptotic computational complexity is math. While searching in dictionary is more or less O(1), searching in list is O(n). To show a practical impact for solution with 100 countries with 100 misspellings each, lets make a test
public class Country
{
public string CountryName { get; set; }
public List<string> CommonMisspellings { get; set; }
public Country()
{
CommonMisspellings = new List<string>();
}
}
static void Main()
{
var counties = new List<Country>();
Dictionary<string, string> dict = new Dictionary<string, string>();
Random rnd = new Random();
List<string> allCountryNames = new List<string>();
List<string> allMissNames = new List<string>();
for (int state = 0; state < 100; ++state)
{
string countryName = state.ToString() + rnd.NextDouble();
allCountryNames.Add(countryName);
var country = new Country { CountryName = countryName };
counties.Add(country);
for (int miss = 0; miss < 100; ++miss)
{
string missname = countryName + miss;
allMissNames.Add(missname);
country.CommonMisspellings.Add(missname);
dict.Add(missname, countryName);
}
}
List<string> testNames = new List<string>();
for (int i = 0; i < 100000; ++i)
{
if (rnd.Next(20) == 1)
{
testNames.Add(allMissNames[rnd.Next(allMissNames.Count)]);
}
else
{
testNames.Add(allCountryNames[rnd.Next(allCountryNames.Count)]);
}
}
System.Diagnostics.Stopwatch st = new System.Diagnostics.Stopwatch();
st.Start();
List<string> repairs = new List<string>();
foreach (var test in testNames)
{
if (counties.Any(c => c.CommonMisspellings.Contains(test)))
{
repairs.Add(counties.First(c => c.CommonMisspellings.Contains(test)).CountryName);
}
}
st.Stop();
Console.WriteLine("List approach: " + st.ElapsedMilliseconds.ToString() + "ms");
st = new System.Diagnostics.Stopwatch();
st.Start();
List<string> repairsDict = new List<string>();
foreach (var test in testNames)
{
if (dict.TryGetValue(test, out var val))
{
repairsDict.Add(val);
}
}
st.Stop();
Console.WriteLine("Dict approach: " + st.ElapsedMilliseconds.ToString() + "ms");
Console.WriteLine("Repaired count: " + repairs.Count
+ ", check " + (repairs.SequenceEqual(repairsDict) ? "OK" : "ERROR"));
Console.ReadLine();
}
And the result is
List approach: 7264ms
Dict approach: 4ms
Repaired count: 4968, check OK
List approach is about 1800x slower, actually more the thousand times slower in this case. The results are as expected. If that is a problem is another question, it depends on concrete usage pattern in concrete application and is out of scope of this post.

Replacing loops with linq code [closed]

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My current code is like this:
var results = new List<Results>();
var items = new List<string>
{
"B,0",
"A,1",
"B,2",
"A,3",
"A,4",
"B,5",
"A,6",
"A,7",
"B,8"
};
int size = 2;
int temp;
var tempResults = new List<int>();
var keys = items.Select(t => t.Split(',')[0]).Distinct().ToList();
//var values = items.Select(t => t.Split(',')[1]).ToList();
//var result = items.SelectMany(k => values, (k, v) => new {k, v});
foreach (var key in keys)
{
temp = 0;
tempResults = new List<int>();
foreach (var item in items)
{
if (item.Split(',')[0] == key)
{
tempResults.Add(Int32.Parse(item.Split(',')[1]));
temp++;
}
if (temp == size)
{
results.Add(new Results
{
Key = key,
Values = new List<int>(tempResults)
});
temp = 0;
tempResults.Clear();
}
}
}
foreach (Results r in results)
{
Console.WriteLine("Key: " + r.Key);
Console.WriteLine("Values: ");
foreach (int i in r.Values)
{
Console.WriteLine(i);
}
}
Everything works fine with it, but I am using two loops to get the results needed. I want to replace them with a LINQ expression and been trying, but can't seem to figure it out. Any help is appreciated.

You could use a combination of LINQ methods: .GroupBy, .Select, SelectMany and some data structures like Tuple<T1, T2>.
Provided that we have class:
class Results
{
public string Key { get; set; }
public List<int> Values { get; set; }
}
The solution could be:
int k = 0;
var result =
items.Select(x => // parse initial string
{
var strValue = x.Split(',');
return Tuple.Create(strValue[0], Convert.ToInt32(strValue[1]));
})
.GroupBy(x => x.Item1, y => y.Item2) // group by key
.Select(x => Tuple.Create(x.Key, x)) // flatten to IEnumerable
.SelectMany(x => // select fixed size data chunks
x.Item2.GroupBy(y => k++ / size, z => z)
.Select(z => Tuple.Create(x.Item1, z)))
.Select(x => // cast to resulting model type
new Results()
{
Key = x.Item1,
Values = x.Item2.ToList()
})
.ToList(); // Return enumeration as list

How about writing a couple extension methods?
const int partitionSize = 2;
var itemLookup = items.ToLookup(x => x.Split(',')[0], x => Int32.Parse(x.Split(',')[1]));
var partitionedItems = itemLookup.Partition(partitionSize);
foreach (var partition in partitionedItems)
foreach (var lookup in partition)
{
Console.WriteLine("Key: " + lookup.Key);
Console.WriteLine("Values: ");
foreach (var i in lookup.ToList())
{
Console.WriteLine(i);
}
}
public static class PartitionExtensions
{
public static IList<ILookup<K, V>> Partition<K, V>(this ILookup<K, V> lookup, int size)
{
return lookup.SelectMany(l => l.ToList().Partition(size).Select(p => p.ToLookup(x => l.Key, x => x))).ToList();
}
public static IList<IList<T>> Partition<T>(this IList<T> list, int size)
{
IList<IList<T>> results = new List<IList<T>>();
var itemCount = list.Count();
var partitionCount = itemCount / size;
//your paritioning method is truncating items that don't make up a full partition
//if you want the remaining items in a partial partition, use this code instead
//var partitionCount = ((itemCount % size == 0) ? itemCount : itemCount + size) / size;
for (var i = 0; i < partitionCount; i++)
{
results.Add(list.Skip(i * size).Take(size).ToList());
}
return results;
}
}

Not really a way to remove the inner loop, but you could shorten a bit your code with:
....
var keys = items.Select(t => t.Split(',')[0]).Distinct().ToList();
foreach (var key in keys)
{
var forKey = items.Where(x => x.Split(',')[0] == key)
.Select(k => int.Parse(k.Split(',')[1]));
for (int x = 0; x < forKey.Count(); x += size)
{
results.Add(new Results
{
Key = key,
Values = forKey.Skip(x).Take(size).ToList()
});
}
}
....
At least this approach will remove the need of the temporary variables and all the if checks inside the loop and will also include in your results the last value for the A key that has only one integer in its list.

Sort a List in which each element contains 2 Values

I have a text file that contains Values in this Format: Time|ID:
180|1
60 |2
120|3
Now I want to sort them by Time. The Output also should be:
60 |2
120|3
180|1
How can I solve this problem? With this:
var path = #"C:\Users\admin\Desktop\test.txt";
List<string> list = File.ReadAllLines(path).ToList();
list.Sort();
for (var i = 0; i < list.Count; i++)
{
Console.WriteLine(list[i]);
}
I got no success ...

3 steps are necessary to do the job:
1) split by the separator
2) convert to int because in a string comparison a 6 comes after a 1 or 10
3) use OrderBy to sort your collection
Here is a linq solution in one line doing all 3 steps:
list = list.OrderBy(x => Convert.ToInt32(x.Split('|')[0])).ToList();
Explanation
x => lambda expression, x denotes a single element in your list
x.Split('|')[0] splits each string and takes only the first part of it (time)
Convert.ToInt32(.. converts the time into a number so that the ordering will be done in the way you desire
list.OrderBy( sorts your collection
EDIT:
Just to understand why you got the result in the first place here is an example of comparison of numbers in string representation using the CompareTo method:
int res = "6".CompareTo("10");
res will have the value of 1 (meaning that 6 is larger than 10 or 6 follows 10)
According to the documentation->remarks:
The CompareTo method was designed primarily for use in sorting or alphabetizing operations.

You should parse each line of the file content and get values as numbers.
string[] lines = File.ReadAllLines("path");
// ID, time
var dict = new Dictionary<int, int>();
// Processing each line of the file content
foreach (var line in lines)
{
string[] splitted = line.Split('|');
int time = Convert.ToInt32(splitted[0]);
int ID = Convert.ToInt32(splitted[1]);
// Key = ID, Value = Time
dict.Add(ID, time);
}
var orderedListByID = dict.OrderBy(x => x.Key).ToList();
var orderedListByTime = dict.OrderBy(x => x.Value).ToList();
Note that I use your ID reference as Key of dictionary assuming that ID should be unique.
Short code version
// Key = ID Value = Time
var orderedListByID = lines.Select(x => x.Split('|')).ToDictionary(x => Convert.ToInt32(x[1]), x => Convert.ToInt32(x[0])).OrderBy(x => x.Key).ToList();
var orderedListByTime = lines.Select(x => x.Split('|')).ToDictionary(x => Convert.ToInt32(x[1]), x => Convert.ToInt32(x[0])).OrderBy(x => x.Value).ToList();

You need to convert them to numbers first. Sorting by string won't give you meaningful results.
times = list.Select(l => l.Split('|')[0]).Select(Int32.Parse);
ids = list.Select(l => l.Split('|')[1]).Select(Int32.Parse);
pairs = times.Zip(ids, (t, id) => new{Time = t, Id = id})
.OrderBy(x => x.Time)
.ToList();

Thank you all, this is my Solution:
var path = #"C:\Users\admin\Desktop\test.txt";
List<string> list = File.ReadAllLines(path).ToList();
list = list.OrderBy(x => Convert.ToInt32(x.Split('|')[0])).ToList();
for(var i = 0; i < list.Count; i++)
{
Console.WriteLine(list[i]);
}

import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class TestClass {
public static void main(String[] args) {
List <LineItem> myList = new ArrayList<LineItem>();
myList.add(LineItem.getLineItem(500, 30));
myList.add(LineItem.getLineItem(300, 20));
myList.add(LineItem.getLineItem(900, 100));
System.out.println(myList);
Collections.sort(myList);
System.out.println("list after sort");
System.out.println(myList);
}
}
class LineItem implements Comparable<LineItem>{
int time;
int id ;
#Override
public String toString() {
return ""+ time + "|"+ id + " ";
}
#Override
public int compareTo(LineItem o) {
return this.time-o.time;
}
public static LineItem getLineItem( int time, int id ){
LineItem l = new LineItem();
l.time=time;
l.id=id;
return l;
}
}

Get list items upto match in C#

I need a better solution for the below code in linq or any other better way, The code gets all items upto match condition.If the condition is process.Name = "process-5" it should return all items upto the condition match including the matched item in this case there will be 5 items in the list.
using System;
using System.Collections.Generic;
namespace ListSelectSample
{
class Process
{
public long Id { get; set; }
public string Name { get; set; }
}
class Program
{
static void Main(string[] args)
{
var processlist = new List<Process>();
for(var count = 1; count <= 10; count++)
processlist.Add(new Process() { Id = count, Name = "Process-" + count});
var selectedprocesslist = new List<Process>();
foreach (var process in processlist)
{
selectedprocesslist.Add(process);
if (process.Name.ToLower().Equals("process-4"))
break;
}
Console.ReadKey();
}
}
}

TakeWhile and SkipWhile should do the trick.
var selectedProcessList = processList
.TakeWhile(x => !x.Name.ToLower().Equals("process-4"))
.ToList();
// Include selected item
if (selectedProcessList.Length < processList.Length)
selectedProcessList.Add(processList
.SkipWhile(x => !x.Name.ToLower().Equals("process-4"))
.First());
EDIT: With the above method's checks and caveats, a hybrid solution might be cleaner:
int idx = processList.Select(x => x.Name.ToLower()).ToList().IndexOf("process-4");
var selectedProcessList = idx < 0 ? processList : processList.Take(idx + 1).ToList();
Like M.kazem is saying, though, a LINQ solution won't be as efficient as the iterative method you are currently using. If your list is small enough, the difference is negligible, but keep that in mind.

You can FindIndex() and Take()
Before find index name equals process-4 then take list from processlist
int index = processlist.FindIndex(x => x.Name.ToLower().Equals("process-4"));
var selectedProcessList = processlist.Take(index+1).ToList();

Try this one.
It need a fix pattern of Name property.
var selectedprocesslist = processlist.Where(o => Convert.ToInt16(o.Name.Split('-')[1]) <= Convert.ToInt16(("process-4").Split('-')[1])).ToList();

Counting words using LinkedList

I have a class WordCount which has string wordDic and int count. Next, I have a List.
I have ANOTHER List which has lots of words inside it. I am trying to use List to count the occurrences of each word inside List.
Below is where I am stuck.
class WordCount
{
string wordDic;
int count;
}
List<WordCount> usd = new List<WordCount>();
foreach (string word in wordsList)
{
if (usd.wordDic.Contains(new WordCount {wordDic=word, count=0 }))
usd.count[value] = usd.counts[value] + 1;
else
usd.Add(new WordCount() {wordDic=word, count=1});
}
I don't know how to properly implement this in code but I am trying to search my List to see if the word in wordsList already exists and if it does, add 1 to count but if it doesn't then insert it inside usd with count of 1.
Note: *I have to use Lists to do this. I am not allowed to use anything else like hash tables...*

This is the answer before you edited to only use lists...btw, what is driving that requirement?
List<string> words = new List<string> {...};
// For case-insensitive you can instantiate with
// new Dictionary<string, int>(StringComparer.OrdinalIgnoreCase)
Dictionary<string, int> counts = new Dictionary<string, int>();
foreach (string word in words)
{
if (counts.ContainsKey(word))
{
counts[word] += 1;
}
else
{
counts[word] = 1;
}
}
If you can only use lists, Can you use List<KeyValuePair<string,int>> counts which is the same thing as a dictionary (although I'm not sure it would guarantee uniqueness). The solution would be very similar. If you can only use lists the following will work.
List<string> words = new List<string>{...};
List<string> foundWord = new List<string>();
List<int> countWord = new List<int>();
foreach (string word in words)
{
if (foundWord.Contains(word))
{
countWord[foundWord.IndexOf(word)] += 1;
}
else
{
foundWord.Add(word);
countWord.Add(1);
}
}
Using your WordCount class
List<string> words = new List<string>{...};
List<WordCount> foundWord = new List<WordCount>();
foreach (string word in words)
{
WordCount match = foundWord.SingleOrDefault(w => w.wordDic == word);
if (match!= null)
{
match.count += 1;
}
else
{
foundWord.Add(new WordCount { wordDic = word, count = 1 });
}
}

You can use Linq to do this.
static void Main(string[] args)
{
List<string> wordsList = new List<string>()
{
"Cat",
"Dog",
"Cat",
"Hat"
};
List<WordCount> usd = wordsList.GroupBy(x => x)
.Select(x => new WordCount() { wordDic = x.Key, count = x.Count() })
.ToList();
}

Use linq: Assuming your list of words :
string[] words = { "blueberry", "chimpanzee", "abacus", "banana", "abacus","apple", "cheese" };
You can do:
var count =
from word in words
group word.ToUpper() by word.ToUpper() into g
where g.Count() > 0
select new { g.Key, Count = g.Count() };
(or in your case, select new WordCount()... it'll depend on how you have your constructor set up)...
the result will look like:

First, all of your class member is private, thus, they could not be accessed somewhere out of your class. Let's assume you're using them in WordCount class too.
Second, your count member is an int. Therefore, follow statement will not work:
usd.count[value] = usd.counts[value] + 1;
And I think you've made a mistype between counts and count.
To solve your problem, find the counter responding your word. If it exists, increase count value, otherwise, create the new one.
foreach (string word in wordsList) {
WordCount counter = usd.Find(c => c.wordDic == word);
if (counter != null) // Counter exists
counter.count++;
else
usd.Add(new WordCount() { wordDic=word, count = 1 }); // Create new one
}

You should use a Dictionary as its faster when using the "Contains" method.
Just replace your list with this
Dictionary usd = new Dictionary();
foreach (string word in wordsList)
{
if (usd.ContainsKey(word.ToLower()))
usd.count[word.ToLower()].count++;
else
usd.Add(word.ToLower(), new WordCount() {wordDic=word, count=1});
}