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

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);
}

String Split to String Array without seperator

Code:
string animals = "cat98dog75";
What i try to achieve :
string a = "cat98";
string b = "dog75";
Question :
How do i split the string using some range delimiter?
example :
animals.split();

I suggest matching with a help of regular expressions:
using System.Text.RegularExpressions;
...
string animals = "cat98dog75";
string[] items = Regex
.Matches(animals, "[a-zA-Z]+[0-9]*")
.OfType<Match>()
.Select(match => match.Value)
.ToArray();
string a = items[0];
string b = items[1];
Concole.Write(string.Join(", ", items));
Outcome:
cat98, dog75
In case you want to split the initial string by equal size chunks:
int size = 5;
string[] items = Enumerable
.Range(0, animals.Length / size + (animals.Length % size > 0 ? 1 : 0))
.Select(index => (index + 1) * size <= animals.Length
? animals.Substring(index * size, size)
: animals.Substring(index * size))
.ToArray();
string a = items[0];
string b = items[1];

This might do the trick for you
string animals = "cat98dog75";
string[] DiffAnimals = Regex.Split(animals, "(?<=[0-9]{2})")
.Where(s => s != String.Empty) //Just to Remove Empty Entries.
.ToArray();

If you want to split the name of the animal and number, try following..
I know its too long....
private static void SplitChars()
{
string animals = "cat98dog75";
Dictionary<string, string> dMyobject = new Dictionary<string, string>();
string sType = "",sCount = "";
bool bLastOneWasNum = false;
foreach (var item in animals.ToCharArray())
{
if (char.IsLetter(item))
{
if (bLastOneWasNum)
{
dMyobject.Add(sType, sCount);
sType = ""; sCount = "";
bLastOneWasNum = false;
}
sType = sType + item;
}
else if (char.IsNumber(item))
{
bLastOneWasNum = true;
sCount = sCount + item;
}
}
dMyobject.Add(sType, sCount);
foreach (var item in dMyobject)
{
Console.WriteLine(item.Key + "- " + item.Value);
}
}
You will get output as
cat - 98
dog - 75
Basically, you are getting type and numbers so if you want to use the count, you don't need to split again...

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 a string containing digits

I'm having a string like,
"abc kskd 8.900 prew"
need to Split this string so that i get the result as "abc kskd" and "8.900 prew"
how can i achieve this with C#?

Get the index of first digit using LINQ then use Substring:
var input = "abc kskd 8.900 prew";
var index = input.Select( (x,idx) => new {x, idx})
.Where(c => char.IsDigit(c.x))
.Select(c => c.idx)
.First();
var part1 = input.Substring(0, index);
var part2 = input.Substring(index);

This should do if you don't need to do something complicated:
var data = "abc kskd 8.900 prew";
var digits = "0123456789".ToCharArray();
var idx = data.IndexOfAny(digits);
if (idx != -1)
{
var firstPart = data.Substring(0, idx - 1);
var secondPart = data.Substring(idx);
}
IndexOfAny is actually very fast.
This could also be modified to separate the string into more parts (using the startIndex parameter), but you didn't ask for that.

straightforward with a regular expression:
var str = "abc kskd 8.900 prew";
var result = Regex.Split(str, #"\W(\d.*)").Where(x => x!="").ToArray();

Try this,
public string[] SplitText(string text)
{
var startIndex = 0;
while (startIndex < text.Length)
{
var index = text.IndexOfAny("0123456789".ToCharArray(), startIndex);
if (index < 0)
{
break;
}
var spaceIndex = text.LastIndexOf(' ', startIndex, index - startIndex);
if (spaceIndex != 0)
{
return new String[] { text.Substring(0, spaceIndex), text.Substring(spaceIndex + 1) };
}
startIndex = index;
}
return new String[] {text};
}

Something similar to what #Dominic Kexel provided, but only if you don't want to use linq.
string[] result = Regex.Split("abc kskd 8.900 prew", #"\w*(?=\d+\.\d)");

Splitting an string into a string array.?

I am facing a problem while executing a sql query in C#.The sql query throws an error when the string contains more than 1000 enteries in the IN CLAUSE .The string has more than 1000 substrings each seperated by ','.
I want to split the string into string array each containing 999 strings seperated by ','.
or
How can i find the nth occurence of ',' in a string.

Pull the string from SQL server into a DataSet using a utilities code like
string strResult = String.Empty;
using (SqlCommand cmd = new SqlCommand())
{
cmd.Connection = conn;
cmd.CommandText = strSQL;
strResult = cmd.ExecuteScalar().ToString();
}
Get the returned string from SQL Server
Split the string on the ','
string[] strResultArr = strResult.Split(',');
then to get the nth string that is seperated by ',' (I think this is what you mean by "How can i find the nth occurence of ',' in a string." use
int n = someInt;
string nthEntry = strResultArr[someInt - 1];
I hope this helps.

You could use a regular expression and the Index property of the Match class:
// Long string of 2000 elements, seperated by ','
var s = String.Join(",", Enumerable.Range(0,2000).Select (e => e.ToString()));
// find all ',' and use '.Index' property to find the position in the string
// to find the first occurence, n has to be 0, etc. etc.
var nth_position = Regex.Matches(s, ",")[n].Index;
To create an array of strings of your requiered size, you could split your string and use LINQ's GroupBy to partition the result, and then joining the resulting groups together:
var result = s.Split(',').Select((x, i) => new {Group = i/1000, Value = x})
.GroupBy(item => item.Group, g => g.Value)
.Select(g => String.Join(",", g));
result now contains two strings, each with 1000 comma seperated elements.

How's this:
int groupSize = 1000;
string[] parts = s.Split(',');
int numGroups = parts.Length / groupSize + (parts.Length % groupSize != 0 ? 1 : 0);
List<string[]> Groups = new List<string[]>();
for (int i = 0; i < numGroups; i++)
{
Groups.Add(parts.Skip(i * groupSize).Take(groupSize).ToArray());
}

Maybe something like this:
string line = "1,2,3,4";
var splitted = line.Split(new[] {','}).Select((x, i) => new {
Element = x,
Index = i
})
.GroupBy(x => x.Index / 1000)
.Select(x => x.Select(y => y.Element).ToList())
.ToList();
After this you should just String.Join each IList<string>.

//initial string of 10000 entries divided by commas
string s = string.Join(", ", Enumerable.Range(0, 10000));
//an array of entries, from the original string
var ss = s.Split(',');
//auxiliary index
int index = 0;
//divide into groups by 1000 entries
var words = ss.GroupBy(w =>
{
try
{
return index / 1000;
}
finally
{
++index;
}
})//join groups into "words"
.Select(g => string.Join(",", g));
//print each word
foreach (var word in words)
Console.WriteLine(word);
Or you may find the indeces in the string and split it into substrings afterwards:
string s = string.Join(", ", Enumerable.Range(0, 100));
int index = 0;
var indeces =
Enumerable.Range(0, s.Length - 1).Where(i =>
{
if (s[i] == ',')
{
if (index < 9)
++index;
else
{
index = 0;
return true;
}
}
return false;
}).ToList();
Console.WriteLine(s.Substring(0, indeces[0]));
for (int i = 0; i < indeces.Count - 1; i++)
{
Console.WriteLine(s.Substring(indeces[i], indeces[i + 1] - indeces[i]));
}
However, I would think over, if it was possible to work with the entries before they are combined into one string. And probably think, if it was possible to prevent the necessity to make a query which needs that great list to pass into the IN statement.

string foo = "a,b,c";
string [] foos = foo.Split(new char [] {','});
foreach(var item in foos)
{
Console.WriteLine(item);
}