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reverse words BUT dot should be at the end

I have sentence:
"I love Marry."
and I would like to get:
"Marry love I." (dot at the end)
How can I do that?
public static string ReverseWords(string originalString)
{
return string.Join(" ", originalString.Split(' ').Where(x => !string.IsNullOrEmpty(x)).Reverse());
}

You can remove the last '.' before the split.
Demo:
public static string ReverseWords(string originalString)
{
var input = originalString.EndsWith(".") ? originalString.Remove(originalString.Length - 1) : originalString; // will trim ending '.'
return string.Join(" ", input.Split().Reverse()) + ".";
}
Try it online!

Try this. I am making it into several statements for readability.
var words = originalString.Split(new [] {' ', '.'}, StringSplitOptions.RemoveEmptyEntries).Reverse();
That gets your words in reverse order, and avoids the need for your Where clause. Then join them back with the period:
return string.Join(' ', words) + '.';

Do it in two steps where you split on . first;
return
string.Join(".",
originalString.Split('.')
.ToList()
.Select(s => string.Join(" ", s.Split(' ').Where(x => !string.IsNullOrEmpty(x)).Reverse())));

For single sentences, remove the dot and append it again in the end.
To remove the dot you can use TrimEnd which will remove all dots from the end of the string. If there is none, nothing is removed:
public static string ReverseWords(string originalString)
{
originalString = originalString.TrimEnd('.');
originalString = string.Join(" ", originalString.Split(' ').Where(x => !string.IsNullOrEmpty(x)).Reverse());
return originalString + ".";
}
For multiple senctences you can split the input string at the ., which will give you an array of sentences without dots. Then you simply reverse each part, append a dot and put them back together (I used a StringBuilder to do that):
public static string ReverseWordsMultiple(string originalString)
{
String[] sentences = originalString.Split(new char[] { '.' }, StringSplitOptions.RemoveEmptyEntries);
StringBuilder builder = new StringBuilder();
foreach (String senctence in sentences)
{
builder.Append(string.Join(" ", senctence.Split(' ').Where(x => !string.IsNullOrEmpty(x)).Reverse()));
builder.Append(". ");
}
return builder.ToString().TrimEnd();
}

C# - Identify the matching character when using String.Split(CharArray)

If I use the Split() function on a string, passing in various split characters as a char[] parameter, and given that the matching split character is removed from the string, how can I identify which character it matched & split on?
string inputString = "Hello, there| world";
char[] splitChars = new char[] { ',','|' }
foreach(string section in inputString.Split(splitChars))
{
Console.WriteLine(section) // [0] Hello [1} there [2] world (no splitChars)
}
I understand that perhaps its not possible to retain this information with my approach. If thats the case, could you suggest an alternative approach?

The C# Regex.Split() method documented here can return the split characters as well as the words between them.
string inputString = "Hello, there| world";
string pattern = #"(,)|([|])";
foreach (string result in Regex.Split(inputString, pattern))
{
Console.WriteLine("'{0}'", result);
}
the result is:
'Hello'
','
' there'
'|'
' world'

Use the Regex.Split() method. I have wrapped this method in the following extension method that is as easy to use as string.Split() itself:
public static string[] ExtendedSplit(this string input, char[] splitChars)
{
string pattern = string.Join("|", splitChars.Select(x => "(" + Regex.Escape(x.ToString()) + ")"));
return Regex.Split(input, pattern);
}
Usage:
string inputString = "Hello, there| world";
char[] splitChars = new char[]{',', '|'};
foreach (string result in inputString.ExtendedSplit(splitChars))
{
Console.WriteLine("'{0}'", result);
}
Output:
'Hello'
','
' there'
'|'
' world'

No, but its rather trivial to write one yourself. Remember, framework methods aren't magic, somebody wrote them. If something doesn't exactly match your needs, write one that does!
static IEnumerable<(string Sector, char Separator)> Split(
this string s,
IEnumerable<char> separators,
bool removeEmptyEntries)
{
var buffer = new StringBuilder();
var separatorsSet = new HashSet<char>(separators);
foreach (var c in s)
{
if (separatorsSet.Contains(c))
{
if (!removeEmptyEntries || buffer.Length > 0)
yield return (buffer.ToString(), c);
buffer.Clear();
}
else
buffer.Append(c);
}
if (buffer.Length > 0)
yield return (buffer.ToString(), default(char));
}

c# split string and remove empty string

I want to remove empty and null string in the split operation:
string number = "9811456789, ";
List<string> mobileNos = number.Split(new string[] { "," }, StringSplitOptions.RemoveEmptyEntries).Select(mobile => mobile.Trim()).ToList();
I tried this but this is not removing the empty space entry

var mobileNos = number.Replace(" ", "")
.Split(new string[] { "," }, StringSplitOptions.RemoveEmptyEntries).ToList();

As I understand it can help to you;
string number = "9811456789, ";
List<string> mobileNos = number.Split(',').Where(x => !string.IsNullOrWhiteSpace(x)).ToList();
the result only one element in list as [0] = "9811456789".
Hope it helps to you.

a string extension can do this in neat way as below
the extension :
public static IEnumerable<string> SplitAndTrim(this string value, params char[] separators)
{
Ensure.Argument.NotNull(value, "source");
return value.Trim().Split(separators, StringSplitOptions.RemoveEmptyEntries).Select(s => s.Trim());
}
then you can use it with any string as below
char[] separator = { ' ', '-' };
var mobileNos = number.SplitAndTrim(separator);

I know it's an old question, but the following works just fine:
string number = "9811456789, ";
List<string> mobileNos = number.Split(new char[] { ',', ' ' }, StringSplitOptions.RemoveEmptyEntries).ToList();
No need for extension methods or whatsoever.

"string,,,,string2".Split(new char[] { ',' }, StringSplitOptions.RemoveEmptyEntries);
return ["string"],["string2"]

The easiest and best solution is to use both StringSplitOptions.TrimEntries to trim the results and StringSplitOptions.RemoveEmptyEntries to remove empty entries, fed in through the pipe operator (|).
string number = "9811456789, ";
List<string> mobileNos = number
.Split(',', StringSplitOptions.TrimEntries | StringSplitOptions.RemoveEmptyEntries)
.ToList();
Checkout the below test results to compare how each option works,

Removing Specified Punctuation From Strings

I have a String that in need to convert into a String[] of each word in the string. However I do not need any white space or any punctuation EXCEPT hyphens and Apostrophes that belong in the word.
Example Input:
Hello! This is a test and it's a short-er 1. - [ ] { } ___)
Example of the Array made from Input:
[ "Hello", "this", "is", "a", "test", "and", "it's", "a", "short-er", "1" ]
Currently this is the code I have tried
(Note: the 2nd gives an error later in the program when string.First() is called):
private string[] ConvertWordsFromFile(String NewFileText)
{
char[] delimiterChars = { ' ', ',', '.', ':', '/', '|', '<', '>', '/', '#', '#', '$', '%', '^', '&', '*', '"', '(', ')', ';' };
string[] words = NewFileText.Split(delimiterChars, StringSplitOptions.RemoveEmptyEntries);
return words;
}
or
private string[] ConvertWordsFromFile(String NewFileText)
{
return Regex.Split(NewFileText, #"\W+");
}
The second example crashes with the following code
private string GroupWordsByFirstLetter(List<String> words)
{
var groups =
from w in words
group w by w.First();
return FormatGroupsByAlphabet(groups);
}
specifically, when w.First() is called.

To remove unwanted characters from a String
string randomString = "thi$ is h#ving s*me inva!id ch#rs";
string excpList ="$#*!";
LINQ Option 1
var chRemoved = randomString
.Select(ch => excpList.Contains(ch) ? (char?)null : ch);
var Result = string.Concat(chRemoved.ToArray());
LINQ Option 2
var Result = randomString.Split().Select(x => x.Except(excList.ToArray()))
.Select(c => new string(c.ToArray()))
.ToArray();

Here is a little something I worked up. Splits on \n and removes any unwanted characters.
private string ValidChars = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ123456789'-";
private IEnumerable<string> SplitRemoveInvalid(string input)
{
string tmp = "";
foreach(char c in input)
{
if(c == '\n')
{
if(!String.IsNullOrEmpty(tmp))
{
yield return tmp;
tmp = "";
}
continue;
}
if(ValidChars.Contains(c))
{
tmp += tmp;
}
}
if (!String.IsNullOrEmpty(tmp)) yield return tmp;
}
Usage could be something like this:
string[] array = SplitRemoveInvalid("Hello! This is a test and it's a short-er 1. - [ ] { } _)")
.ToArray();
I didnt actually test it, but it should work. If it doesnt, it should be easy enough to fix.

Use string.Split(char [])
string strings = "4,6,8\n9,4";
string [] split = strings .Split(new Char [] {',' , '\n' });
OR
Try below if you get any unwanted empty items. String.Split Method (String[], StringSplitOptions)
string [] split = strings .Split(new Char [] {',' , '\n' },
StringSplitOptions.RemoveEmptyEntries);

This can be done quite easily with a RegEx, by matching words. I am using the following RegEx, which will allow hyphens and apostrophes in the middle of words, but will strip them out if they occur at a word boundary.
\w(?:[\w'-]*\w)?
See it in action here.
In C# it could look like this:
private string[] ConvertWordsFromFile(String NewFileText)
{
return (from m in new Regex(#"\w(?:[\w'-]*\w)?").Matches(NewFileText)
select m.Value).ToArray();
}
I am using LINQ to get an array of words from the MatchCollection returned by Matches.

Removing specific special characters from a string

I would like to remove spaces(' '), dots('.') and hyphens(-) from a string, using a regular expression.
My current approach:
string input = "hello how --r dsbadb...dasjidhdsa.dasbhdgsa--dasb";
var res = input
.ToCharArray()
.Where(i => i != ' ' && i != '-' && i != '.')
.Aggregate(" ", (a, b) => a + b);

string filteredInput = Regex.Replace(input, "[ .-]+", "");
should be easier and more readable.

var result = string.Concat(input.Where(c => !new[] { '.', ' ', '-' }.Contains(c)));

string result = Regex.Replace(input, "[\s\.-]+", "");
\s would target space, \. would target dots, and - would target hyphens and will replace them with empty string