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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;

Getting substring between two separators in an arbitrary position

I have following string:
string source = "Test/Company/Business/Department/Logs.tvs/v1";
The / character is the separator between various elements in the string. I need to get the last two elements of the string. I have following code for this purpose. This works fine. Is there any faster/simpler code for this?
CODE
static void Main()
{
string component = String.Empty;
string version = String.Empty;
string source = "Test/Company/Business/Department/Logs.tvs/v1";
if (!String.IsNullOrEmpty(source))
{
String[] partsOfSource = source.Split('/');
if (partsOfSource != null)
{
if (partsOfSource.Length > 2)
{
component = partsOfSource[partsOfSource.Length - 2];
}
if (partsOfSource.Length > 1)
{
version = partsOfSource[partsOfSource.Length - 1];
}
}
}
Console.WriteLine(component);
Console.WriteLine(version);
Console.Read();
}

Why no regular expression? This one is fairly easy:
.*/(?<component>.*)/(?<version>.*)$
You can even label your groups so for your match all you need to do is:
component = myMatch.Groups["component"];
version = myMatch.Groups["version"];

The following should be faster, as it only scans as much of the string as it needs to to find two / and it doesn't bother splitting up the whole string:
string component = "";
string version = "";
string source = "Test/Company/Business/Department/Logs.tvs/v1";
int last = source.LastIndexOf('/');
if (last != -1)
{
int penultimate = source.LastIndexOf('/', last - 1);
version = source.Substring(last + 1);
component = source.Substring(penultimate + 1, last - penultimate - 1);
}
That said, as with all performance questions: profile! Try the two side-by-side with a big list of real-life inputs and see which is fastest.
(Also, this will leave empty strings rather than throw an exception if there is no slash in the input... but throw if source is null, lazy me.)

Your approach is the most suitable one given that your are looking for substrings at a particular index. A LINQ expression to do the same in this case will likely not improve the code or its readability.
For reference, there is some great information from Microsoft here on working with strings and LINQ. In particular see the article here which covers some examples with both LINQ and RegEx.
EDIT: +1 For Matt's named group within RegEx approach... that's the nicest solution I've seen.

Your code mostly looks fine. A couple of points to note:
String.Split() will never return null, so you don't need the null check on it.
If the source string has fewer than two / characters, how would you deal with that? (The Original Post was updated to address this)
Do you really want to just output empty strings if your source string is null or empty (or invalid)? If you have specific expectations about the nature of the input, you may want to consider failing fast when those expectations are not met.

You could try something like this but I doubt it would be much faster. You could do some meassurements with System.Diagnostics.StopWatch to see if you feel the need.
string source = "Test/Company/Business/Department/Logs.tvs/v1";
int index1 = source.LastIndexOf('/');
string last = source.Substring(index1 + 1);
string substring = source.Substring(0, index1);
int index2 = substring.LastIndexOf('/');
string secondLast = substring.Substring(index2 + 1);

I would try
string source = "Test/Company/Business/Department/Logs.tvs/v1";
var components = source.Split('/').Reverse().Take(2);
String last = string.Empty;
var enumerable = components as string[] ?? components.ToArray();
if (enumerable.Count() == 2)
last = enumerable.FirstOrDefault();
var secondLast = enumerable.LastOrDefault();
Hope this will help

you can retrieve the last two words using the process as below:
string source = "Test/Company/Business/Department/Logs.tvs/v1";
String[] partsOfSource = source.Split('/');
if(partsOfSourch.length>2)
for(int i=partsOfSourch.length-2;i<=partsOfSource.length-1;i++)
console.writeline(partsOfSource[i]);

Help me delete the last three chars of any string please!

Test string:
the%20matrix%20
How can I delete the last three chars? Using this code gives me an out of index exception:
y = y.Substring(y.Length - 4, y.Length - 1);

Seems this isn't your REAL problem; if you want to remove that "%20", you should use:
string test = "the%20matrix%20";
string clean = HttpUtility.UrlDecode(test);
if (clean.Length > 2) // if you still want to strip last chars...
clean = clean.Substring(0, clean.Length - 3);

As dalovega said, you need the first parameter of Substring to be 0 and the second Length - 3. As an alternative:
if(y.Length >= 3)
{
y = y.Remove(y.Length - 3)
}

You want
y.Substring(0, y.Length-4)

If you want to delete the last three characters, you need the first parameter of your Substring method to be zero.

You need to check that the string is at least 3 characters long first.
if (y.Length > 2)
{
}
As others have said the version of Substring you want parameters are startIndex and length.
Though what do you want to do with 1 or 2 character strings?

I found this post from a search I was looking for. I had a delimiter I was building with a string builder, and concat and wanted to remove the last delimiter.
var delim = "{somedelimiter}";
var sb = new StringBuilder();
//concat the values into one string
foreach (var val in values)
{
sb.Append(val);
sb.Append(delim);
}
var finalValue = sb.ToString();
finalValue = finalValue.Remove(finalValue.Length - delim.Length);

string.Remove(string.LastIndexOf(" stringTo "));

String functions

I want to search for a given string, within another string (Ex. find if "something" exists inside "something like this". How can I do the following? :
Know the position in which "something" is located (in the curr. ex. this is = 0.
Extract everything to the left or to the right, up to the char. found (see 1).
Extract a substring beggining where the sought string was found, all the way to X amount of chars (in Visual Basic 6/VBA I would use the Mid function).

string searched = "something like this";
1.
int pos = searched.IndexOf("something");
2.
string start = searched.Substring(0, pos);
string endstring = searched.Substring(pos);
3.
string mid = searched.Substring(pos, x);

Have you looked at the String.SubString() method? You can use the IndexOf() method to see if the substring exists first.

Take a look at the System.String member functions, in particular the IndexOf method.

Use int String.IndexOf(String).

I would do something like this:
string s = "I have something like this";
//question No. 1
int pos = s.IndexOf("something");
//quiestion No. 2
string[] separator = {"something"};
string[] leftAndRightEntries = s.Split(separator, StringSplitOptions.None);
//question No. 3
int x = pos + 10;
string substring = s.Substring(pos, x);

I would avoid using Split, as it's designed to give you multiple results. I would stick with the code in the first example, though the second block should actually read...
string start = searched.Substring(0, pos);
string endstring;
if(pos < searched.Length - 1)
endstring = searched.Substring(pos + "something".Length);
else
endstring = string.Empty
The key difference is accounting for the length of the string to find (hence the rather odd-looking "something".Length, as this example is designed for you to be able to plop in your own variable).

C# Using Substring, how do I extract this string?

I want to extract the first folder in the URL below, in this example it is called 'extractThisFolderName' but the folder could have any name and be any length. With this in mind how can I use substring to extract the first folder name?
The string: www.somewebsite.com/extractThisFolderName/leave/this/behind
String folderName = path.Substring(path.IndexOf(#"/"),XXXXXXXXXXX);
It's the length I'm struggling with.

If you're getting a Uri, why not just do uri.Segments[0]?
Or even path.Split(new Char[] { '/' })[1] ?

If you're going to be using each path part, you can use:
String[] parts = path.Split('/');
At which point you can access the "extractThisFolderName" part by accessing parts[1].
Alternatively, you can do this to splice out the foldername:
int firstSlashIndex = path.IndexOf('/');
int secondSlashIndex = path.IndexOf('/', firstSlashIndex + 1);
String folderName = path.Substring(firstSlashIndex + 1, secondSlashIndex - firstSlashIndex);

Daniel's answer gives you other practical ways of doing it. Another alternative using substring:
int start = path.IndexOf('/')+1; // Note that you don't need a verbatim string literal
int secondSlash = path.IndexOf('/', start);
return path.Substring(start, secondSlash-start);
You'll want to add some error checking in there, of course :)

The problem also lends itself to regular expressions. An expression like:
(?<host>.*?)/(?<folder>.*?)/
Is clear about what's going on and you can get the data out by those names.

int start = path.IndexOf('/');
int end = path.IndexOf('/', start + 1);
if (end == -1) end = path.Length;
string folderName = path.Substring(start + 1, end - start - 1);
EDIT: Daniel Schaffer's answer about using uri segments is preferable, but left this in as it may be your path is not really a valid uri.

You could do:
string myStr = "www.somewebsite.com/extractThisFolderName/leave/this/behind";
int startIndex = myStr.IndexOf('/') + 1;
int length = myStr.IndexOf('/', startIndex) - startIndex;
Console.WriteLine(myStr.Substring(startIndex, length));
At the same point I assume this is being done in ASP.Net if so I think there might be another way to get this without doign the querying.

folderName.Split('/')[1]