Get string between two strings in a string

Question

I have a string like    super exemple of string key   text I want to keep - end of my string    I want to just keep the string which is between  key     and   -     How can I do that   Must I use a Regex or can I do it in another way

User · Answer

You already have some good answers and I realize the code I am providing is far from the most efficient and clean. However, I thought it might be useful for educational purposes. We can use pre-built classes and libraries all day long. But without understanding the inner-workings, we are simply mimicking and repeating and will never learn anything. This code works and is more basic or "virgin" than some of the others:

char startDelimiter = ':';
char endDelimiter = '-';

Boolean collect = false;

string parsedString = "";

foreach (char c in originalString)
{
    if (c == startDelimiter)
         collect = true;

    if (c == endDelimiter)
         collect = false;

    if (collect == true && c != startDelimiter)
         parsedString += c;
}

You end up with your desired string assigned to the parsedString variable. Keep in mind that it will also capture proceeding and preceding spaces. Remember that a string is simply an array of characters that can be manipulated like other arrays with indices etc.

Take care.

User · Answer

string str  super exemple of string key   text I want to keep - end of my string           int startIndex   str IndexOf  key      key  Length          int endIndex   str IndexOf  -            string newString   str Substring startIndex  endIndex - startIndex

User · Answer

Since the   and the - are unique you could use    string input  string output  input    super example of string key   text I want to keep - end of my string   output   input Split new char           -     1

User · Answer

I think this works       static void Main string   args                String text    One 1 Two 2 ThreeFour 34            Console WriteLine betweenStrings text   One              1         Console WriteLine betweenStrings text   Two              2         Console WriteLine betweenStrings text   ThreeFour             34          Console ReadKey                public static String betweenStrings String text  String start  String end                int p1   text IndexOf start    start Length          int p2   text IndexOf end  p1            if  end        return  text Substring p1            else return text Substring p1  p2 - p1

User · Answer

Regex is overkill here   You could use string Split with the overload that takes a string   for the delimiters but that would also be overkill   Look at Substring and IndexOf - the former to get parts of a string given and index and a length and the second for finding indexed of inner strings characters

User · Answer

var matches   Regex Matches input       lt  key           -       This returns only the value s  between  key    and the following occurance of  -

User · Answer

getStringBetween startStr  endStr  fullStr        string startIndex   fullStr indexOf startStr       string endIndex  fullStr indexOf endStr       return fullStr substring startIndex   startStr length  endIndex

User · Answer

When questions are stated in terms of a single example ambiguities are inevitably be present  This question is no exception  For the example given in the question the desired string is clear  super example of string key   text I want to keep - end of my string                                                    However  this string is but an example of strings and boundary strings for which certain substrings are to be identified  I will consider a generic string with generic boundary strings  represented as follows  abc FF def PP ghi PP jkl FF mno PP pqr FF stu FF vwx PP yza                                            PP is the preceding string  FF is the following string and the party hats indicate which substrings are to be matched   In the example given in the question key    is the preceding string and - is the following string   I have assumed that PP and FF are preceded and followed by word boundaries  so that PPA and FF8 are not matched   My assumptions  as reflected by the party hats  are as follows   The first substring PP may be preceded by one  or more  FF substrings  which  if present  are disregarded  If PP is followed by one or more PPs before FF is encountered  the following PPs are part of the substring between the preceding and following strings  If PP is followed by one or more FFs before a PP is encounter  the first FF following PP is considered to be the following string   Note that many of the answers here deal with only strings of the form abc PP def FF ghi              or abc PP def FF ghi PP jkl FF mno                            One may use a regular expression  code constructs  or a combination of the two to identify the substrings of interest  I make no judgement as to which approach is best  I will only present the following regular expression that will match the substrings of interest     lt   bPP b        bFF b        bFF b   Start your engine 1 I tested this with the PCRE  PHP  regex engine  but as the regex is not at all exotic  I am sure it will work with the  NET regex engine  which is very robust   The regex engine performs the following operations     lt              begin a positive lookbehind    bPP b        match  PP                  end positive lookbehind                 begin a non-capture group                 begin a negative lookahead      bFF b      match  FF                  end negative lookahead                 match any character                 end non-capture group                 execute non-capture group 0  times                 begin positive lookahead     bFF b       match  FF                  end positive lookahead  This technique  of matching one character at a time  following the preceding string  until the character is F and is followed by F  or more generally  the character beings the string that constitutes the following string   is called Tempered Greedy Token Solution  Naturally  the regex would have to be modified  if possible  if the assumptions I set out above are changed  1  Move the cursor around for detailed explanations

User · Answer

If you are looking for a 1 line solution  this is it   s Substring s IndexOf  eT      eT  Length  Split  97  ToCharArray    First     The whole 1 line solution  with System Linq   using System  using System Linq   class OneLiner       static void Main                 string s    TextHereTisImortant973End     Between  eT  and  97          Console WriteLine s Substring s IndexOf  eT      eT  Length                              Split  97  ToCharArray    First

User · Answer

If you want to handle multiple occurrences of substring pairs  it won t be easy without RegEx   Regex Matches input    String Empty      key           lt   -     RegexOptions Singleline           input    String Empty avoids argument null exception       keeps 1st substring and   lt   keeps 2nd substring   RegexOptions Singleline allows newline between substring pair        If order  amp  occurrence count of substrings doesn t matter  this quick  amp  dirty one may be an option    var parts   input  Split new string      key        -      StringSplitOptions None   string result   parts  Length  gt   3   result 1    input    At least it avoids most exceptions  by returning the original string if none single substring match

User · Answer

You can use the extension method below   public static string GetStringBetween this string token  string first  string second                            if   token Contains first   return              var afterFirst   token Split new     first    StringSplitOptions None  1            if   afterFirst Contains second   return              var result   afterFirst Split new     second    StringSplitOptions None  0            return result          Usage is    var token    super exemple of string key   text I want to keep - end of my string   var keyValue   token GetStringBetween  key        -

User · Answer

You can do it without regex   input Split new string     key     StringSplitOptions None  1         Split  -   0         Trim

User · Answer

As I  always say nothing is impossible   string value     super exemple of string key   text I want to keep - end of my string   Regex regex   new Regex    key                 Match match   regex Match value   if  match Success        Messagebox Show match Value          Remeber that should add reference of System Text RegularExpressions   Hope That I Helped

User · Answer

private string gettxtbettwen string txt  string first  string last                 StringBuilder sb   new StringBuilder txt           int pos1   txt IndexOf first     first Length          int len    txt Length   - pos1           string reminder   txt Substring pos1  len             int pos2   reminder IndexOf last  - last Length  1                       return reminder Substring 0  pos2

User · Answer

Something like this perhaps  private static string Between string text  string from  string to        return text  text IndexOf from  from Length   text IndexOf to  text IndexOf from

User · Answer

Perhaps  a good way is just to cut out a substring   String St    super exemple of string key   text I want to keep - end of my string    int pFrom   St IndexOf  key         key     Length  int pTo   St LastIndexOf   -      String result   St Substring pFrom  pTo - pFrom

User · Answer

I used the code snippet from Vijay Singh Rana which basically does the job  But it causes problems if the firstString does already contain the lastString  What I wanted was extracting a access token from a JSON Response  no JSON Parser loaded   My firstString was   access token       and my lastString was     I ended up with a little modification   string Between string str  string firstString  string lastString            int pos1   str IndexOf firstString    firstString Length      int pos2   str Substring pos1  IndexOf lastString       return str Substring pos1  pos2

User · Answer

Here is the way how i can do that     public string Between string STR   string FirstString  string LastString                       string FinalString               int Pos1   STR IndexOf FirstString    FirstString Length          int Pos2   STR IndexOf LastString           FinalString   STR Substring Pos1  Pos2 - Pos1           return FinalString

User · Answer

string input    super exemple of string key   text I want to keep - end of my string   var match   Regex Match input    key        -   Groups 1  Value    or with just string operations  var start   input IndexOf  key        6  var match2   input Substring start  input IndexOf  -   - start

User · Answer

In C  8 0 and above  you can use the range operator    as in var s    quot header-THE TARGET STRING 7z quot   var from   s IndexOf  quot - quot      quot - quot  Length  var to   s IndexOf  quot  7z quot    var versionString   s from  to       THE TARGET STRING  See documentation for details

User · Answer

Depending on how robust flexible you want your implementation to be  this can actually be a bit tricky  Here s the implementation I use   public static class StringExtensions            lt summary gt          takes a substring between two anchor strings  or the end of the string if that anchor is null           lt  summary gt           lt param name  this  gt a string lt  param gt           lt param name  from  gt an optional string to search after lt  param gt           lt param name  until  gt an optional string to search before lt  param gt           lt param name  comparison  gt an optional comparison for the search lt  param gt           lt returns gt a substring based on the search lt  returns gt      public static string Substring this string  this  string from   null  string until   null  StringComparison comparison   StringComparison InvariantCulture                var fromLength    from    string Empty  Length          var startIndex    string IsNullOrEmpty from                  this IndexOf from  comparison    fromLength               0           if  startIndex  lt  fromLength    throw new ArgumentException  from  Failed to find an instance of the first anchor                   var endIndex    string IsNullOrEmpty until                  this IndexOf until  startIndex  comparison                  this Length           if  endIndex  lt  0    throw new ArgumentException  until  Failed to find an instance of the last anchor               var subString    this Substring startIndex  endIndex - startIndex           return subString              usage  var between    a - to keep x more stuff  Substring from   -   until   x       returns   to keep

User · Answer

A working LINQ solution  string str    quot super example of string key   text I want to keep - end of my string quot   string res   new string str SkipWhile c   gt  c                                     Skip 1                              TakeWhile c   gt  c     -                               ToArray    Trim    Console WriteLine res      text I want to keep

User · Answer

or  with a regex   using System Text RegularExpressions        var value       Regex Match           super exemple of string key   text I want to keep - end of my string            key        -         Groups 1  Value    with a running example   You can decide if its overkill   or  as an under validated extension method  using System Text RegularExpressions   public class Test       public static void Main                 var value                    super exemple of string key   text I want to keep - end of my string                       Between                           key                                -              Console WriteLine value            public static class Ext       static string Between this string source  string left  string right                return Regex Match                  source                  string Format   0      1    left  right                Groups 1  Value

[c#] Get string between two strings in a string

Examples related to c#

Examples related to regex

Examples related to string