Split and then Joining the String step by step - C# Linq - c#

Here is my string:
www.stackoverflow.com/questions/ask/user/end
I split it with / into a list of separated words:myString.Split('/').ToList()
Output:
www.stackoverflow.com
questions
ask
user
end
and I need to rejoin the string to get a list like this:
www.stackoverflow.com
www.stackoverflow.com/questions
www.stackoverflow.com/questions/ask
www.stackoverflow.com/questions/ask/user
www.stackoverflow.com/questions/ask/user/end
I think about linq aggregate but it seems it is not suitable here. I want to do this all through linq

You can try iterating over it with foreach
var splitted = "www.stackoverflow.com/questions/ask/user/end".Split('/').ToList();
string full = "";
foreach (var part in splitted)
{
full=$"{full}/{part}"
Console.Write(full);
}
Or use linq:
var splitted = "www.stackoverflow.com/questions/ask/user/end".Split('/').ToList();
var list = splitted.Select((x, i) => string.Join("/", a.Take(i + 1)));

Linq with side effect:
string prior = null;
var result = "www.stackoverflow.com/questions/ask/user/end"
.Split('/')
.Select(item => prior == null
? prior = item
: prior += "/" + item)
.ToList();
Let's print it out
Console.WriteLine(string.Join(Environment.NewLine, result));
Outcome:
www.stackoverflow.com
www.stackoverflow.com/questions
www.stackoverflow.com/questions/ask
www.stackoverflow.com/questions/ask/user
www.stackoverflow.com/questions/ask/user/end

Linq without side effects ;)
Enumerable.Aggregate can be used here if we use List<T> as a result.
var raw = "www.stackoverflow.com/questions/ask/user/end";
var actual =
raw.Split('/')
.Aggregate(new List<string>(),
(list, word) =>
{
var combined = list.Any() ? $"{list.Last()}/{word}" : word;
list.Add(combined);
return list;
});

without Linq write below code,
var str = "www.stackoverflow.com/questions/ask/user/end";
string[] full = str.Split('/');
string Result = string.Empty;
for (int i = 0; i < full.Length; i++)
{
Console.WriteLine(full[i]);
}
for (int i = 0; i < full.Length; i++)
{
if (i == 0)
{
Result = full[i];
}
else
{
Result += "/" + full[i];
}
Console.WriteLine(Result);
}

Related

Get count of unique characters between first and last letter

I'm trying to get the unique characters count that are between the first and last letter of a word. For example: if I type Yellow the expected output is Y3w, if I type People the output should be P4e and if I type Money the output should be M3y. This is what I tried:
//var strArr = wordToConvert.Split(' ');
string[] strArr = new[] { "Money","Yellow", "People" };
List<string> newsentence = new List<string>();
foreach (string word in strArr)
{
if (word.Length > 2)
{
//ignore 2-letter words
string newword = null;
int distinctCount = 0;
int k = word.Length;
int samecharcount = 0;
int count = 0;
for (int i = 1; i < k - 2; i++)
{
if (word.ElementAt(i) != word.ElementAt(i + 1))
{
count++;
}
else
{
samecharcount++;
}
}
distinctCount = count + samecharcount;
char frst = word[0];
char last = word[word.Length - 1];
newword = String.Concat(frst, distinctCount.ToString(), last);
newsentence.Add(newword);
}
else
{
newsentence.Add(word);
}
}
var result = String.Join(" ", newsentence.ToArray());
Console.WriteLine("Output: " + result);
Console.WriteLine("----------------------------------------------------");
With this code I'm getting the expect output for Yellow, but seems that is not working with People and Money. What can I do to fix this issue or also I'm wondering is maybe there is a better way to do this for example using LINQ/Regex.
Here's an implementation that uses Linq:
string[] strArr = new[]{"Money", "Yellow", "People"};
List<string> newsentence = new List<string>();
foreach (string word in strArr)
{
if (word.Length > 2)
{
// we want the first letter, the last letter, and the distinct count of everything in between
var first = word.First();
var last = word.Last();
var others = word.Skip(1).Take(word.Length - 2);
// Case sensitive
var distinct = others.Distinct();
// Case insensitive
// var distinct = others.Select(c => char.ToLowerInvariant(c)).Distinct();
string newword = first + distinct.Count().ToString() + last;
newsentence.Add(newword);
}
else
{
newsentence.Add(word);
}
}
var result = String.Join(" ", newsentence.ToArray());
Console.WriteLine(result);
Output:
M3y Y3w P4e
Note that this doesn't take account of case, so the output for FiIsSh is 4.
Maybe not the most performant, but here is another example using linq:
var words = new[] { "Money","Yellow", "People" };
var transformedWords = words.Select(Transform);
var sentence = String.Join(' ', transformedWords);
public string Transform(string input)
{
if (input.Length < 3)
{
return input;
}
var count = input.Skip(1).SkipLast(1).Distinct().Count();
return $"{input[0]}{count}{input[^1]}";
}
You can implement it with the help of Linq. e.g. (C# 8+)
private static string EncodeWord(string value) => value.Length <= 2
? value
: $"{value[0]}{value.Substring(1, value.Length - 2).Distinct().Count()}{value[^1]}";
Demo:
string[] tests = new string[] {
"Money","Yellow", "People"
};
var report = string.Join(Environment.NewLine, tests
.Select(test => $"{test} :: {EncodeWord(test)}"));
Console.Write(report);
Outcome:
Money :: M3y
Yellow :: Y3w
People :: P4e
A lot of people have put up some good solutions. I have two solutions for you: one uses LINQ and the other does not.
LINQ, Probably not much different from others
if (str.Length < 3) return str;
var midStr = str.Substring(1, str.Length - 2);
var midCount = midStr.Distinct().Count();
return string.Concat(str[0], midCount, str[str.Length - 1]);
Non-LINQ
if (str.Length < 3) return str;
var uniqueLetters = new Dictionary<char, int>();
var midStr = str.Substring(1, str.Length - 2);
foreach (var c in midStr)
{
if (!uniqueLetters.ContainsKey(c))
{
uniqueLetters.Add(c, 0);
}
}
var midCount = uniqueLetters.Keys.Count();
return string.Concat(str[0], midCount, str[str.Length - 1]);
I tested this with the following 6 strings:
Yellow
Money
Purple
Me
You
Hiiiiiiiii
Output:
LINQ: Y3w, Non-LINQ: Y3w
LINQ: M3y, Non-LINQ: M3y
LINQ: P4e, Non-LINQ: P4e
LINQ: Me, Non-LINQ: Me
LINQ: Y1u, Non-LINQ: Y1u
LINQ: H1i, Non-LINQ: H1i
Fiddle
Performance-wise I'd guess they're pretty much the same, if not identical, but I haven't run any real perf test on the two approaches. I can't imagine they'd be much different, if at all. The only real difference is that the second route expands Distinct() into what it probably does under the covers anyway (I haven't looked at the source to see if that's true, but that's a pretty common way to get a count of . And the first route is certainly less code.
I Would use Linq for that purpose:
string[] words = new string[] { "Yellow" , "People", "Money", "Sh" }; // Sh for 2 letter words (or u can insert 0 and then remove the trinary operator)
foreach (string word in words)
{
int uniqeCharsInBetween = word.Substring(1, word.Length - 2).ToCharArray().Distinct().Count();
string result = word[0] + (uniqeCharsInBetween == 0 ? string.Empty : uniqeCharsInBetween.ToString()) + word[word.Length - 1];
Console.WriteLine(result);
}

How to perform word search using LINQ?

I have a list which contains the name of suppliers. Say
SuppId Supplier Name
----------------------------------
1 Aardema & Whitelaw
2 Aafedt Forde Gray
3 Whitelaw & Sears-Ewald
using following LINQ query
supplierListQuery = supplierListQuery.Where(x => x.SupplierName.Contains(SearchKey));
I can return records correctly in the following conditions,
1) If i am using search string as "Whitelaw & Sears-Ewald" it will return 3rd record.
2) If i am using "Whitelaw" or "Sears-Ewald" it will return 3rd record.
But how can i return 3rd record if i am giving search string as "Whitelaw Sears-Ewald". It always returns 0 records.
Can i use ALL to get this result, but i dont know how to use it for this particular need.
What I usually do in this situation is split the words into a collection, then perform the following:
var searchopts = SearchKey.Split(' ').ToList();
supplierListQuery = supplierListQuery
.Where(x => searchopts.Any(y=> x.SupplierName.Contains(y)));
This works for me:
IEnumerable<string> keyWords = SearchKey.Split('');
supplierListQuery = supplierListQuery
.AsParallel()
.Where
(
x => keyWords.All
(
keyword => x.SupplierName.ContainsIgnoreCase(keyword)
)
);
Thank you all for your quick responses. But the one which worked or a easy fix to handle this was timothyclifford's note on this. Like he said i alterd my answer to this
string[] filters = SearchKey.ToLower().Split(new[] { ' ' });
objSuppliersList = (from x in objSuppliersList
where filters.All(f => x.SupplierName.ToLower().Contains(f))
select x).ToList();
Now it returns the result for all my serach conditions.
Because "Whitelaw" appears in both you will get both records. Otherwise there is no dynamic way to determine you only want the last one. If you know you only have these 3 then append .Last() to get the final record.
supplierListQuery = supplierListQuery.Where(x => x.SupplierName.Contains(SearchKey.Split(' ')[0]));
You need to use some sort of string comparer to create your own simple Search Engine and then you can find strings that are most likely to be included in your result :
public static class SearchEngine
{
public static double CompareStrings(string val1, string val2)
{
if ((val1.Length == 0) || (val2.Length == 0)) return 0;
if (val1 == val2) return 100;
double maxLength = Math.Max(val1.Length, val2.Length);
double minLength = Math.Min(val1.Length, val2.Length);
int charIndex = 0;
for (int i = 0; i < minLength; i++) { if (val1.Contains(val2[i])) charIndex++; }
return Math.Round(charIndex / maxLength * 100);
}
public static List<string> Search(this string[] values, string searchKey, double threshold)
{
List<string> result = new List<string>();
for (int i = 0; i < values.Length; i++) if (CompareStrings(values[i], searchKey) > threshold) result.Add(values[i]);
return result;
}
}
Example of usage :
string[] array = { "Aardema & Whitelaw", "Aafedt Forde Gray", "Whitelaw & Sears-Ewald" };
var result = array.Search("WhitelawSears-Ewald", 80);
// Results that matches this string with 80% or more
foreach (var item in result)
{
Console.WriteLine(item);
}
Output: Whitelaw & Sears-Ewald
If you want an easy (not very handy) solution,
var result = supplierListQuery
.Select(x => normalize(x.SupplierName))
.Where(x => x.Contains(normalize(SearchKey)));
string normalize(string inputStr)
{
string retVal = inputStr.Replace("&", "");
while (retVal.IndexOf(" ") >= 0)
{
retVal = retVal.Replace(" ", " ");
}
return retVal;
}

I want substring from set of string after a pattern exist in c#

I have 3 string ---
m60_CLDdet2_LOSS2CLF_060520469434_R0RKE_52_GU
m60_CLDdet2_LOSS2CLF_060520469434_R10KE_52_TCRER
m60_CLDdet2_LOSS2CLF_060520469434_R0HKE_52_NT
and I want R0RKE_52_GU, R10KE_52_TCRER,R0HKE_52_NT.
Note: m60_CLDdet2_LOSS2CLF_060520469434 is varying so I want to find substring if R0RKE or R10KE or R0HKE exists
I would suggest using a Regular expression for this, it is much more versatile for pattern matching.
var matches = System.Text.RegularExpressions.Regex.Matches(text, #"(R0RKE|R10KE|R0HKE).*");
I want to find substring if R0RKE or R10KE or R0HKE exists
This LINQ query returns the desired result:
var strings=new[]{"m60_CLDdet2_LOSS2CLF_060520469434_R0RKE_52_GU","m60_CLDdet2_LOSS2CLF_060520469434_R10KE_52_TCRER","m60_CLDdet2_LOSS2CLF_060520469434_R0HKE_52_NT"};
string[] starts = { "R0RKE", "R10KE", "R0HKE" };
var result = strings
.Select(str => new { str, match = starts.FirstOrDefault(s => str.IndexOf("_" + s) >= 0)})
.Where(x => x.match != null)
.Select(x => x.str.Substring(x.str.IndexOf(x.match)));
Console.Write(String.Join(",", result)); // R0RKE_52_GU,R10KE_52_TCRER,R0HKE_52_NT
I write it into static method:
private static string TakeIt(string inputString)
{
if (!Regex.IsMatch(inputString, "(R0RKE|R10KE|R0HKE)"))
{
return string.Empty;
}
var regex = new Regex(#"_");
var occurances = regex.Matches(inputString);
var index = occurances[3].Index + 1;
return inputString.Substring(index, inputString.Length - index);
}
void Main()
{
var string1 = "m60_CLDdet2_LOSS2CLF_060520469434_R0RKE_52_GU";
var string2 = "m60_CLDdet2_LOSS2CLF_060520469434_R10KE_52_TCRER";
var string3 = "m60_CLDdet2_LOSS2CLF_060520469434_R0HKE_52_NT";
var string4 = "m60_CLDdet2_LOSS2CLF_060520469434_hhhhh";
Console.WriteLine(TakeIt(string1));
Console.WriteLine(TakeIt(string2));
Console.WriteLine(TakeIt(string3));
Console.WriteLine(TakeIt(string4));
}
Hope this help.
Update: added .Any - it simplifies the code and it's just as same efficient.
If you just need to check for three strings inside string array you can do :
static string[] GetStrings(string[] dirty, string[] lookUpValues)
{
List<string> result = new List<string>();
for (int i = 0; i < dirty.Length; i++) if (lookUpValues.Any(dirty[i].Contains)) result.Add(dirty[i]);
return result.ToArray();
}
Usage: string[] result = GetStrings(dirty, new[] {"R0RKE", "R10KE", "R0HKE"});
Also you can use LINQ query and Regex.Matches as others advised.

Split string with Pipe for a chunk in simplest way?

Got a string let say
string mystring = "A\nB\nC\nD\nE\nF\nG\n"
want to convert it with | for chunk of 5
string Converted string ="ABCDE|FG"
Any one liner solution..
I am going this way
private void TweakInputLines(string InputData)
{
List<string> lstInput = new List<string>();
if (!string.IsNullOrEmpty(InputData))
{
lstInput = InputData.Split('\n').ToList();
if (lstInput.Count > 4)
{
}
}
}
Try this one liner
string mystring = "A\nB\nC\nD\nE\nF\nG\n";
var result = Regex.Replace(mystring.Replace("\n", ""), ".{5}", "$0|");
Here is the demo.
General solution (preserving variable length lines):
string input = "A\nBC\nDEF\nG\nH\nI\nJKL\nMN\nO\nP\nQR\nS";
string output = string.Join("|", input.Split('\n')
.Select((s, i) => new { s, i })
.GroupBy(p => p.i / 5)
.Select(g => string.Join("", g.Select(p => p.s))));
Output:
ABCDEFGH|IJKLMNOP|QRS
Update
If you use .Net 3.5, then you need to add .ToArray() calls in string.Join() methods.
string input = "A\nBC\nDEF\nG\nH\nI\nJKL\nMN\nO\nP\nQR\nS";
string output = string.Join("|", input.Split('\n')
.Select((s, i) => new { s, i })
.GroupBy(p => p.i / 5)
.Select(g => string.Join("", g.Select(p => p.s).ToArray()))
.ToArray());
Update 2
Another option is to use slightly modified solution by #SriramSakthivel
string input = "A\nBC\nDEF\nG\nH\nI\nJKL\nMN\nO\nP\nQR\nS";
string output = Regex.Replace(input, #"((?:.*\n){4}.*)\n", "$1|").Replace("\n", "");
Simple code is
private void TweakInputLines(string InputData)
{
List<string> lstInput = new List<string>();
var returnstring = "";
if (!string.IsNullOrEmpty(InputData))
{
lstInput = InputData.Split('\n').ToList();
if (lstInput.Count > 9999)
{
int counter = 0;
foreach (var eachcharitem in lstInput)
{
counter++;
returnstring = returnstring + eachcharitem;
if (counter == 5)
{
returnstring = returnstring + "|";
counter = 0;
}
}
}
}
}
Another solution with the use of Linq - its more or less a "one-liner":
string mystring = "A\nB\nC\nD\nE\nF\nG\n";
var str = mystring
.Select((value, index) => new { Index = index, Value = value }) // insert Index
.GroupBy(i => (int)(i.Index / 5)) // group by index / 5
.Select(value => String.Join("",value.Select(temp => temp.Value))) // create string out of grouped chars
.Aggregate((a,b) => a + "|" + b); // create one string out of splitted chars
// and join the "|"-string in between

How to get string after specific string?

How to get string after text "playlist:" ?
var YT= "tag:youtube.com,2008:user:hollywoodlife09:playlist:PLDovhwKa3P88MwGzYxMDMfiAiiEWxAJYj" ;
What I did :
string[] s = YT.Split(':');
But it will give me array i.e s[0],s[1] ... and I am searching for something which can give result after specific text.
I want string after "playlist:", I know it may be easy with Regex,but currently I don't have any idea for Regex..
You can use Substring method
var output = inputString.SubString(inputString.LastIndexOf("playlist") + 8);
Or in this case it can be done using Last method via Split:
string output = YT.Split(':').Last();
Using regex replace, remove everything before the :playlist: with empty string.
string playlist = Regex.Replace(YT, ".*:playlist:", "");
more reusably,
static IEnumerable<KeyValuePair<string, string>> SplitPairs(
this string source,
params char[] seperators)
{
var values = source.Split(seperators);
for(var i = 0; i < values.Length; i += 2)
{
yield return new KeyValuePair<string, string>(
values[i],
values[i + 1]);
}
}
so you could do,
var yTlookup = YT.SplitPairs(':').ToDictionary(p => p.Key, p => p.Value);
var playList = yTLookup["playlist"];
or if you don't want an extension,
var segments = YS.Split(new[] { ':' });
var ySlookup = Enumerable.Range(0, segemnts.Length / 2)
.ToDictionary(i => segments[i * 2], i => segments[(i * 2) + 1]);
so you can do,
var playlist = ysLookup["playlist"];
either approach pays off as soon as you want another value from the sequence.
The regex is .+playlist:([^:])

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