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How to strip a string from the point a hyphen is found within the string C#

I'm currently trying to strip a string of data that is may contain the hyphen symbol.
E.g. Basic logic:
string stringin = "test - 9894"; OR Data could be == "test";
if (string contains a hyphen "-"){
Strip stringin;
output would be "test" deleting from the hyphen.
}
Console.WriteLine(stringin);
The current C# code i'm trying to get to work is shown below:
string Details = "hsh4a - 8989";
var regexItem = new Regex("^[^-]*-?[^-]*$");
string stringin;
stringin = Details.ToString();
if (regexItem.IsMatch(stringin)) {
stringin = stringin.Substring(0, stringin.IndexOf("-") - 1); //Strip from the ending chars and - once - is hit.
}
Details = stringin;
Console.WriteLine(Details);
But pulls in an Error when the string does not contain any hyphen's.

How about just doing this?
stringin.Split('-')[0].Trim();
You could even specify the maximum number of substrings using overloaded Split constructor.
stringin.Split('-', 1)[0].Trim();

Your regex is asking for "zero or one repetition of -", which means that it matches even if your input does NOT contain a hyphen. Thereafter you do this
stringin.Substring(0, stringin.IndexOf("-") - 1)
Which gives an index out of range exception (There is no hyphen to find).
Make a simple change to your regex and it works with or without - ask for "one or more hyphens":
var regexItem = new Regex("^[^-]*-+[^-]*$");
here -------------------------^

It seems that you want the (sub)string starting from the dash ('-') if original one contains '-' or the original string if doesn't have dash.
If it's your case:
String Details = "hsh4a - 8989";
Details = Details.Substring(Details.IndexOf('-') + 1);

I wouldn't use regex for this case if I were you, it makes the solution much more complex than it can be.
For string I am sure will have no more than a couple of dashes I would use this code, because it is one liner and very simple:
string str= entryString.Split(new [] {'-'}, StringSplitOptions.RemoveEmptyEntries)[0];
If you know that a string might contain high amount of dashes, it is not recommended to use this approach - it will create high amount of different strings, although you are looking just for the first one. So, the solution would look like something like this code:
int firstDashIndex = entryString.IndexOf("-");
string str = firstDashIndex > -1? entryString.Substring(0, firstDashIndex) : entryString;

you don't need a regex for this. A simple IndexOf function will give you the index of the hyphen, then you can clean it up from there.
This is also a great place to start writing unit tests as well. They are very good for stuff like this.
Here's what the code could look like :
string inputString = "ho-something";
string outPutString = inputString;
var hyphenIndex = inputString.IndexOf('-');
if (hyphenIndex > -1)
{
outPutString = inputString.Substring(0, hyphenIndex);
}
return outPutString;

Extract sub-string between two certain words right to left side

Example String
This is an important example about regex for my work.
I can extract important example about regex with this (?<=an).*?(?=for) snippet. Reference
But i would like to extract to string right to left side. According to this question's example; first position must be (for) second position must be (an).
I mean extracting process works back ways.
I tried what i want do as below codes in else İf case, but it doesn't work.
public string FnExtractString(string _QsString, string _QsStart, string _QsEnd, string _QsWay = "LR")
{
if (_QsWay == "LR")
return Regex.Match(_QsString, #"(?<=" + _QsStart + ").*?(?=" + _QsEnd + ")").Value;
else if (_QsWay == "RL")
return Regex.Match(_QsString, #"(?=" + _QsStart + ").*?(<=" + _QsEnd + ")").Value;
else
return _QsString;
}
Thanks in advance.
EDIT
My real example as below
#Var|First String|ID_303#Var|Second String|ID_304#Var|Third String|DI_t55
When i pass two string to my method (for example "|ID_304" and "#Var|") I would like to extract "Second String" but this example is little peace of my real string and my string is changeable.

No need for forward or backward lookahead! You could just:
(.*)\san\s.*\sfor\s
The \s demands whitespace, so you don't match an import*an*t.

One potential problem in your current solution is that the string passed in contains special characters, which needs to be escaped with Regex.Escape before concatenation:
return Regex.Match(_QsString, #"(?<=" + Regex.Escape(_QsStart) + ").*?(?=" + Regex.Escape(_QsEnd) + ")").Value;
For your other requirement of matching RL, I don't understand your requirement.

Shorthand way to remove last forward slash and trailing characters from string

If I have the following string:
/lorem/ipsum/dolor
and I want this to become:
/lorem/ipsum
What is the short-hand way of removing the last forward slash, and all characters following it?
I know how I can do this by spliting the string into a List<> and removing the last item, and then joining, but is there a shorter way of writing this?
My question is not URL specific.

You can use Substring() and LastIndexOf():
str = str.Substring(0, str.LastIndexOf('/'));
EDIT (suggested comment)
To prevent any issues when the string may not contain a /, you could use something like:
int lastSlash = str.LastIndexOf('/');
str = (lastSlash > -1) ? str.Substring(0, lastSlash) : str;
Storing the position in a temp-variable would prevent the need to call .LastIndexOf('/') twice, but it could be dropped in favor of a one-line solution instead.

If there is '/' at the end of the url, remove it.
If not; just return the original one.
var url = this.Request.RequestUri.ToString();
url = url.EndsWith("/") ? url.Substring(0, url.Length - 1) : url;
url += #"/mycontroller";

You can do something like str.Remove(str.LastIndexOf("/")), but there is no built-in method to do what you want.
Edit: you could also use the Uri object to traverse directories, although it does not give exactly what you want:
Uri baseUri = new Uri("http://domain.com/lorem/ipsum/dolor");
Uri myUri = new Uri(baseUri, ".");
// myUri now contains http://domain.com/lorem/ipsum/

One simple way would be
String s = "domain.com/lorem/ipsum/dolor";
s = s.Substring(0, s.LastIndexOf('/'));
Console.WriteLine(s);
Another maybe
String s = "domain.com/lorem/ipsum/dolor";
s = s.TrimEnd('/');
Console.WriteLine(s);

You can use the regex /[^/]*$ and replace with the empty string:
var fixed = new Regex("/[^/]*$").Replace("domain.com/lorem/ipsum/dolor", "")
But it's probably overkill here. #newfurniturey's answer of Substring with LastIndexOf is probably best.

I like to create a String Extension for stuff like this:
/// <summary>
/// Returns with suffix removed, if present
/// </summary>
public static string TrimIfEndsWith(
this string value,
string suffix)
{
return
value.EndsWith(suffix) ?
value.Substring(0, value.Length - suffix.Length) :
value;
}
You can then use like this:
var myString = "/lorem/ipsum/dolor";
myStringClean = myString.TrimIfEndsWith("/dolor");
You now have a re-usable extension across all of your projects that can be used to remove one trailing character or multiple.

using System.IO;
mystring.TrimEnd(Path.AltDirectorySeparatorChar); // To remove "/"
mystring.TrimEnd(Path.DirectorySeparatorChar); // To remove "\"

while (input.Last() == '/' || input.Last() == '\\')
{
input = input.Substring(0, input.Length - 1);
}

Thank you #Curt for your question.
I slightly improved #newfurniturey's code, and here is my version.
if(str.Contains('/')){
str = str.Substring(0, str.LastIndexOf('/'));
}

I'm way late to the party, but if you're using C# 8.0+, another clean approach would be to use the range operator:
if (urlStr.EndsWith("/")) urlStr = urlStr[..^1];
If you're curious as to how this works, take a look at the spec for ranges in C#:
https://learn.microsoft.com/en-us/dotnet/csharp/language-reference/proposals/csharp-8.0/ranges
tldr; urlStr[..^1] roughly translates to something along the lines of "Give me a substring comprised of the characters contained within the range of index 0 to whatever index is 1 away from the last index.".
In other words, it's similar to...
urlStr.Substring(0, urlStr.Length-1)

find string using c#?

I am trying find a string in below string.
http://example.com/TIGS/SIM/Lists/Team Discussion/DispForm.aspx?ID=1779
by using http://example.com/TIGS/SIM/Lists string. How can I get Team Discussion word from it?
Some times strings will be
http://example.com/TIGS/SIM/Lists/Team Discussion/DispForm.aspx?ID=1779
I need `Team Discussion`
http://example.com/TIGS/ALIF/Lists/Artifical Lift Discussion Forum 2/DispForm.aspx?ID=8
I need `Artifical Lift Discussion Forum 2`

If you're always following that pattern, I recommend #Justin's answer. However, if you want a more robust method, you can always couple the System.Uri and Path.GetDirectoryName methods, then perform a String.Split. Like this example:
String url = #"http://example.com/TIGS/SIM/Lists/Team Discussion/DispForm.aspx?ID=1779";
System.Uri uri = new System.Uri(url);
String dir = Path.GetDirectoryName(uri.AbsolutePath);
String[] parts = dir.Split(new[]{ Path.DirectorySeparatorChar });
Console.WriteLine(parts[parts.Length - 1]);
The only major problem, however, is you're going to wind up with a path that's been "encoded" (i.e. your space is now going to be represented by a %20)

This solution will get you the last directory of your URL regardless of how many directories are in your URL.
string[] arr = s.Split('/');
string lastPart = arr[arr.Length - 2];
You could combine this solution into one line, however it would require splitting the string twice, once for the values, the second for the length.

If you wanted to see a regular expression example:
string input = "http://example.com/TIGS/SIM/Lists/Team Discussion/DispForm.aspx?ID=1779";
string given = "http://example.com/TIGS/SIM/Lists";
System.Text.RegularExpressions.Regex regex = new System.Text.RegularExpressions.Regex(given + #"\/(.+)\/");
System.Text.RegularExpressions.Match match = regex.Match(input);
Console.WriteLine(match.Groups[1]); // Team Discussion

Here's a simple approach, assuming that your URL always has the same number of slashes before the are you want:
var value = url.Split(new[]{'/'}, StringSplitOptions.RemoveEmptyEntries)[5];

Here is another solution that provides the following advantages:
Does not require the use of regular expressions.
Does not require a certain 'count' of slashes be present (indexing based of a specific number). I consider this a key benefit because it makes the code less likely to fail if some part of the URL changes. Ultimately it is best to base your parsing logic off which part of the text's structure you consider least likely to change.
This method, however, DOES rely on the following assumptions, which I consider to be the least likely to change:
URL must have "/Lists/" right before target text.
URL must have "/" right after target text.
Basically, I just split the string twice, using text that I expect to be surrounding the area I am interested in.
String urlToSearch = "http://example.com/TIGS/SIM/Lists/Team Discussion/DispForm.aspx";
String result = "";
// First, get everthing after "/Lists/"
string[] temp1 = urlToSearch.Split(new String[] { "/Lists/" }, StringSplitOptions.RemoveEmptyEntries);
if (temp1.Length > 1)
{
// Next, get everything before the first "/"
string[] temp2 = temp1[1].Split(new String[] { "/" }, StringSplitOptions.RemoveEmptyEntries);
result = temp2[0];
}
Your answer will then be stored in the 'result' variable.

Remove all problematic characters in an intelligent way in C#

Is there any .Net library to remove all problematic characters of a string and only leave alphanumeric, hyphen and underscore (or similar subset) in an intelligent way? This is for using in URLs, file names, etc.
I'm looking for something similar to stringex which can do the following:
A simple prelude
"simple English".to_url =>
"simple-english"
"it's nothing at all".to_url =>
"its-nothing-at-all"
"rock & roll".to_url =>
"rock-and-roll"
Let's show off
"$12 worth of Ruby power".to_url =>
"12-dollars-worth-of-ruby-power"
"10% off if you act now".to_url =>
"10-percent-off-if-you-act-now"
You don't even wanna trust Iconv for this next part
"kick it en Français".to_url =>
"kick-it-en-francais"
"rock it Español style".to_url =>
"rock-it-espanol-style"
"tell your readers 你好".to_url =>
"tell-your-readers-ni-hao"

You can try this
string str = phrase.ToLower(); //optional
str = str.Trim();
str = Regex.Replace(str, #"[^a-z0-9\s_]", ""); // invalid chars
str = Regex.Replace(str, #"\s+", " ").Trim(); // convert multiple spaces into one space
str = str.Substring(0, str.Length <= 400 ? str.Length : 400).Trim(); // cut and trim it
str = Regex.Replace(str, #"\s", "-");

Perhaps this question here can help you on your way. It gives you code on how Stackoverflow generates its url's (more specifically, how question names are turned into nice urls.
Link to Question here, where Jeff Atwood shows their code

From your examples, the closest thing I've found (although I don't think it does everything that you're after) is:
My Favorite String Extension Methods in C#
and also:
ÜberUtils - Part 3 : Strings
Since neither of these solutions will give you exactly what you're after (going from the examples in your question) and assuming that the goal here is to make your string "safe", I'd second Hogan's advice and go with Microsoft's Anti Cross Site Scripting Library, or at least use that as a basis for something that you create yourself, perhaps deriving from the library.
Here's a link to a class that builds a number of string extension methods (like the first two examples) but leverages Microsoft's AntiXSS Library:
Extension Methods for AntiXss
Of course, you can always combine the algorithms (or similar ones) used within the AntiXSS library with the kind of algorithms that are often used in websites to generate "slug" URL's (much like Stack Overflow and many blog platforms do).
Here's an example of a good C# slug generator:
Improved C# Slug Generator

You could use HTTPUtility.UrlEncode, but that would encode everything, and not replace or remove problematic characters. So your spaces would be + and ' would be encoded as well. Not a solution, but maybe a starting point

If the goal is to make the string "safe" I recommend Mirosoft's anti-xss libary

There will be no library capable of what you want since you are stating specific rules that you want applied, e.g. $x => x-dollars, x% => x-percent. You will almost certainly have to write your own method to acheive this. It shouldn't be too difficult. A string extension method and use of one or more Regex's for making the replacements would probably be quite a nice concise way of doing it.
e.g.
public static string ToUrl(this string text)
{
return text.Trim().Regex.Replace(text, ..., ...);
}

Something the Ruby version doesn't make clear (but the original Perl version does) is that the algorithm it's using to transliterate non-Roman characters is deliberately simplistic -- "better than nothing" in both senses. For example, while it does have a limited capability to transliterate Chinese characters, this is entirely context-insensitive -- so if you feed it Japanese text then you get gibberish out.
The advantage of this simplistic nature is that it's pretty trivial to implement. You just have a big table of Unicode characters and their corresponding ASCII "equivalents". You could pull this straight from the Perl (or Ruby) source code if you decide to implement this functionality yourself.

I'm using something like this in my blog.
public class Post
{
public string Subject { get; set; }
public string ResolveSubjectForUrl()
{
return Regex.Replace(Regex.Replace(this.Subject.ToLower(), "[^\\w]", "-"), "[-]{2,}", "-");
}
}

I couldn't find any library that does it, like in Ruby, so I ended writing my own method. This is it in case anyone cares:
/// <summary>
/// Turn a string into something that's URL and Google friendly.
/// </summary>
/// <param name="str"></param>
/// <returns></returns>
public static string ForUrl(this string str) {
return str.ForUrl(true);
}
public static string ForUrl(this string str, bool MakeLowerCase) {
// Go to lowercase.
if (MakeLowerCase) {
str = str.ToLower();
}
// Replace accented characters for the closest ones:
char[] from = "ÂÃÄÀÁÅÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝàáâãäåçèéêëìíîïðñòóôõöøùúûüýÿ".ToCharArray();
char[] to = "AAAAAACEEEEIIIIDNOOOOOOUUUUYaaaaaaceeeeiiiidnoooooouuuuyy".ToCharArray();
for (int i = 0; i < from.Length; i++) {
str = str.Replace(from[i], to[i]);
}
// Thorn http://en.wikipedia.org/wiki/%C3%9E
str = str.Replace("Þ", "TH");
str = str.Replace("þ", "th");
// Eszett http://en.wikipedia.org/wiki/%C3%9F
str = str.Replace("ß", "ss");
// AE http://en.wikipedia.org/wiki/%C3%86
str = str.Replace("Æ", "AE");
str = str.Replace("æ", "ae");
// Esperanto http://en.wikipedia.org/wiki/Esperanto_orthography
from = "ĈĜĤĴŜŬĉĝĥĵŝŭ".ToCharArray();
to = "CXGXHXJXSXUXcxgxhxjxsxux".ToCharArray();
for (int i = 0; i < from.Length; i++) {
str = str.Replace(from[i].ToString(), "{0}{1}".Args(to[i*2], to[i*2+1]));
}
// Currencies.
str = new Regex(#"([¢€£\$])([0-9\.,]+)").Replace(str, #"$2 $1");
str = str.Replace("¢", "cents");
str = str.Replace("€", "euros");
str = str.Replace("£", "pounds");
str = str.Replace("$", "dollars");
// Ands
str = str.Replace("&", " and ");
// More aesthetically pleasing contractions
str = str.Replace("'", "");
str = str.Replace("’", "");
// Except alphanumeric, everything else is a dash.
str = new Regex(#"[^A-Za-z0-9-]").Replace(str, "-");
// Remove dashes at the begining or end.
str = str.Trim("-".ToCharArray());
// Compact duplicated dashes.
str = new Regex("-+").Replace(str, "-");
// Let's url-encode just in case.
return str.UrlEncode();
}