CODEWITHSUNDEEP
c#stringfind
Wilson
Wilson

Reputation: 8768

Find text in string with C#

How can I find given text within a string? After that, I'd like to create a new string between that and something else. For instance, if the string was:

This is an example string and my data is here

And I want to create a string with whatever is between "my " and " is" how could I do that? This is pretty pseudo, but hopefully it makes sense.

Upvotes: 107

Views: 683915

Answers (17)

user12116884
user12116884

Reputation:

for .net 6 can use next code

public static string? Crop(string? text, string? start, string? end = default)
{
    if (text == null) return null;

    string? result;

    var startIndex = string.IsNullOrEmpty(start) ? 0 : text.IndexOf(start);

    if (startIndex < 0) return null;

    startIndex += start?.Length ?? 0;

    if (string.IsNullOrEmpty(end))
    {
        result = text.Substring(startIndex);
    }
    else
    {
        var endIndex = text.IndexOf(end, startIndex);

        if (endIndex < 0) return null;

        result = text.Substring(startIndex, endIndex - startIndex);
    }

    return result;
}

Upvotes: 0

Dr. Rahul Jha
Dr. Rahul Jha

Reputation: 1054

Correct answer here without using any pre-defined method.

    static void WordContainsInString()
    {
        int f = 0;
        Console.WriteLine("Input the string");
        string str = Console.ReadLine();
        Console.WriteLine("Input the word to search");
        string word = Console.ReadLine();
        int l = str.Length;
        int c = word.Length;

        for (int i = 0; i < l; i++)
        {
            if (str[i] == word[0])
            {
                for (int K = i + 1, j = 1; j < c; j++, K++)
                {
                    if (str[K] == word[j])
                    {
                        f++;
                    }
                    else 
                    { 
                        f = 0; 
                    }
                }
            }
        }
        if (f == c - 1)
        {
            Console.WriteLine("matching");
        }
        else
        {
            Console.WriteLine("not found");
        }
        Console.ReadLine();
    }

Upvotes: 0

009topersky
009topersky

Reputation: 101

I have different approach on ReplaceTextBetween() function.

public static string ReplaceTextBetween(this string strSource, string strStart, string strEnd, string strReplace)
        {
            if (strSource.Contains(strStart) && strSource.Contains(strEnd))
            {
                var startIndex = strSource.IndexOf(strStart, 0) + strStart.Length;

                var endIndex = strSource.IndexOf(strEnd, startIndex);

                var strSourceLength = strSource.Length;

                var strToReplace = strSource.Substring(startIndex, endIndex - startIndex);

                var concatStart = startIndex + strToReplace.Length;

                var beforeReplaceStr = strSource.Substring(0, startIndex);

                var afterReplaceStr = strSource.Substring(concatStart, strSourceLength - endIndex);

                return string.Concat(beforeReplaceStr, strReplace, afterReplaceStr);
            }

            return strSource;
        }

Upvotes: 0

Oscar Jara
Oscar Jara

Reputation: 14187

Use this method:

public static string getBetween(string strSource, string strStart, string strEnd)
{
    if (strSource.Contains(strStart) && strSource.Contains(strEnd))
    {
        int Start, End;
        Start = strSource.IndexOf(strStart, 0) + strStart.Length;
        End = strSource.IndexOf(strEnd, Start);
        return strSource.Substring(Start, End - Start);
    }

    return "";
}

How to use it:

string source = "This is an example string and my data is here";
string data = getBetween(source, "my", "is");

Upvotes: 222

Rokonz Zaz
Rokonz Zaz

Reputation: 176

Simply add this code:

if (string.Contains("search_text")) { MessageBox.Show("Message."); }

Upvotes: 1

Jo&#227;o Ox Oc
Jo&#227;o Ox Oc

Reputation: 83

This is the correct way to replace a portion of text inside a string (based upon the getBetween method by Oscar Jara):

public static string ReplaceTextBetween(string strSource, string strStart, string strEnd, string strReplace)
    {
        int Start, End, strSourceEnd;
        if (strSource.Contains(strStart) && strSource.Contains(strEnd))
        {
            Start = strSource.IndexOf(strStart, 0) + strStart.Length;
            End = strSource.IndexOf(strEnd, Start);
            strSourceEnd = strSource.Length - 1;

            string strToReplace = strSource.Substring(Start, End - Start);
            string newString = string.Concat(strSource.Substring(0, Start), strReplace, strSource.Substring(Start + strToReplace.Length, strSourceEnd - Start));
            return newString;
        }
        else
        {
            return string.Empty;
        }
    }

The string.Concat concatenates 3 strings:

  1. The string source portion before the string to replace found - strSource.Substring(0, Start)
  2. The replacing string - strReplace
  3. The string source portion after the string to replace found - strSource.Substring(Start + strToReplace.Length, strSourceEnd - Start)

Upvotes: 2

Taran
Taran

Reputation: 3221

First find the index of text and then substring

        var ind = Directory.GetCurrentDirectory().ToString().IndexOf("TEXT To find");

        string productFolder = Directory.GetCurrentDirectory().ToString().Substring(0, ind);

Upvotes: 0

Kemal Duran
Kemal Duran

Reputation: 1522

This is the simplest way:

if(str.Contains("hello"))

Upvotes: 89

Johnny Cee
Johnny Cee

Reputation: 434

Here's my function using Oscar Jara's function as a model.

public static string getBetween(string strSource, string strStart, string strEnd) {
   const int kNotFound = -1;

   var startIdx = strSource.IndexOf(strStart);
   if (startIdx != kNotFound) {
      startIdx += strStart.Length;
      var endIdx = strSource.IndexOf(strEnd, startIdx);
      if (endIdx > startIdx) {
         return strSource.Substring(startIdx, endIdx - startIdx);
      }
   }
   return String.Empty;
}

This version does at most two searches of the text. It avoids an exception thrown by Oscar's version when searching for an end string that only occurs before the start string, i.e., getBetween(text, "my", "and");.

Usage is the same:

string text = "This is an example string and my data is here";
string data = getBetween(text, "my", "is");

Upvotes: 7

Debendra Dash
Debendra Dash

Reputation: 5596

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Threading;
using System.Diagnostics;

namespace oops3
{


    public class Demo
    {

        static void Main(string[] args)
        {
            Console.WriteLine("Enter the string");
            string x = Console.ReadLine();
            Console.WriteLine("enter the string to be searched");
            string SearchText = Console.ReadLine();
            string[] myarr = new string[30];
             myarr = x.Split(' ');
            int i = 0;
            foreach(string s in myarr)
            {
                i = i + 1;
                if (s==SearchText)
                {
                    Console.WriteLine("The string found at position:" + i);

                }

            }
            Console.ReadLine();
        }


    }












        }

Upvotes: 3

Reza Taibur
Reza Taibur

Reputation: 261

  string WordInBetween(string sentence, string wordOne, string wordTwo)
        {

            int start = sentence.IndexOf(wordOne) + wordOne.Length + 1;

            int end = sentence.IndexOf(wordTwo) - start - 1;

            return sentence.Substring(start, end);


        }

Upvotes: 2

Fandango68
Fandango68

Reputation: 4838

Except for @Prashant's answer, the above answers have been answered incorrectly. Where is the "replace" feature of the answer? The OP asked, "After that, I'd like to create a new string between that and something else".

Based on @Oscar's excellent response, I have expanded his function to be a "Search And Replace" function in one.

I think @Prashant's answer should have been the accepted answer by the OP, as it does a replace.

Anyway, I've called my variant - ReplaceBetween().

public static string ReplaceBetween(string strSource, string strStart, string strEnd, string strReplace)
{
    int Start, End;
    if (strSource.Contains(strStart) && strSource.Contains(strEnd))
    {
        Start = strSource.IndexOf(strStart, 0) + strStart.Length;
        End = strSource.IndexOf(strEnd, Start);
        string strToReplace = strSource.Substring(Start, End - Start);
        string newString = strSource.Concat(Start,strReplace,End - Start);
        return newString;
    }
    else
    {
        return string.Empty;
    }
}

Upvotes: 3

MichelZ
MichelZ

Reputation: 4394

You could use Regex:

var regex = new Regex(".*my (.*) is.*");
if (regex.IsMatch("This is an example string and my data is here"))
{
    var myCapturedText = regex.Match("This is an example string and my data is here").Groups[1].Value;
    Console.WriteLine("This is my captured text: {0}", myCapturedText);
}

Upvotes: 29

Lori Lalonde - MSFT
Lori Lalonde - MSFT

Reputation: 368

If you know that you always want the string between "my" and "is", then you can always perform the following:

string message = "This is an example string and my data is here";

//Get the string position of the first word and add two (for it's length)
int pos1 = message.IndexOf("my") + 2;

//Get the string position of the next word, starting index being after the first position
int pos2 = message.IndexOf("is", pos1);

//use substring to obtain the information in between and store in a new string
string data = message.Substring(pos1, pos2 - pos1).Trim();

Upvotes: 0

Prashant
Prashant

Reputation: 41

You can do it compactly like this:

string abc = abc.Replace(abc.Substring(abc.IndexOf("me"), (abc.IndexOf("is", abc.IndexOf("me")) + 1) - abc.IndexOf("size")), string.Empty);

Upvotes: 4

RAMESH
RAMESH

Reputation: 31

static void Main(string[] args)
    {

        int f = 0;
        Console.WriteLine("enter the string");
        string s = Console.ReadLine();
        Console.WriteLine("enter the word to be searched");
        string a = Console.ReadLine();
        int l = s.Length;
        int c = a.Length;

        for (int i = 0; i < l; i++)
        {
            if (s[i] == a[0])
            {
                for (int K = i + 1, j = 1; j < c; j++, K++)
                {
                    if (s[K] == a[j])
                    {
                        f++;
                    }
                }
            }
        }
        if (f == c - 1)
        {
            Console.WriteLine("matching");
        }
        else
        {
            Console.WriteLine("not found");
        }
        Console.ReadLine();
    }

Upvotes: 3

Kevin DiTraglia
Kevin DiTraglia

Reputation: 26058

 string string1 = "This is an example string and my data is here";
 string toFind1 = "my";
 string toFind2 = "is";
 int start = string1.IndexOf(toFind1) + toFind1.Length;
 int end = string1.IndexOf(toFind2, start); //Start after the index of 'my' since 'is' appears twice
 string string2 = string1.Substring(start, end - start);

Upvotes: 9

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