Develop Reference

Remove characters from a specific index character

I would like to know how can i remove characters in a string from a specific index like :
string str = "this/is/an/example"
I want to remove all characters from the third '/' including so it would be like this:
str = "this/is/an"
I tried with substring and regex but i cant find a solution.

Using string operations:
str = str.Substring(0, str.IndexOf('/', str.IndexOf('/', str.IndexOf('/') + 1) + 1));
Using regex:
str = Regex.Replace(str, #"^(([^/]*/){2}[^/]*)/.*$", "$1");

To get "this/is/an":
string str = "this/is/an/example";
string new_string = str.Remove(str.LastIndexOf('/'));
If you need to keep the slash:
string str = "this/is/an/example";
string new_string = str.Remove(str.LastIndexOf('/')+1);
This expects there to be at least one slash. If none are present, you should check it beforehand to not throw an exception:
string str = "this.s.an.example";
string newStr = str;
if (str.Contains('/'))
newStr = str.Remove(str.LastIndexOf('/'));
If its importaint to get the third one, make a dynamic method for it, like this. Input the string, and which "folder" you want returned. 3 in your example will return "this/is/an":
static string ReturnNdir(string sDir, int n)
{
while (sDir.Count(s => s == '/') > n - 1)
sDir = sDir.Remove(sDir.LastIndexOf('/'));
return sDir;
}

This regex is the answer: ^[^/]*\/[^/]*\/[^/]*. It will capture the first three chunks.
var regex = new Regex("^[^/]*\\/[^/]*\\/[^/]*", RegexOptions.Compiled);
var value = regex.Match(str).Value;

I think the best way of doing that it's creating a extension
string str = "this/is/an/example";
str = str.RemoveLastWord();
//specifying a character
string str2 = "this.is.an.example";
str2 = str2.RemoveLastWord(".");
With this static class:
public static class StringExtension
{
public static string RemoveLastWord(this string value, string separator = "")
{
if (string.IsNullOrWhiteSpace(value))
return string.Empty;
if (string.IsNullOrWhiteSpace(separator))
separator = "/";
var words = value.Split(Char.Parse(separator));
if (words.Length == 1)
return value;
value = string.Join(separator, words.Take(words.Length - 1));
return value;
}
}

Retrieving string from a string which is in between two String?

i have a string Like
"Hello i want to go."
my code give "want to go."
but i need string between " i " and " to " how can i get this? my code is as below.
string[] words = Regex.Split("Hello i want to go.", " i ");
string respons = words[1];

string input = "Hello i want to go.";
Regex regex = new Regex(#".*\s[Ii]{1}\s(\w*)\sto\s.*");
Match match = regex.Match(input);
string result = string.Empty;
if (match.Success)
{
result = match.Groups[1].Value;
}
This regex will match any 'word' between 'i' (not case sensitive) and 'to'.
EDIT: changed ...to.* => to\s.* as suggested in the comments.

string input = "Hello I want to go.";
string result = input.Split(" ")[2];
If you want the word after the "i" then:
string result = input.Split(" i ")[1].Split(" ")[0];

Use
string s = "Hello i want to go.";
string[] words = s.split(' ');
string response = wor

just do it with one simple line of code
var word = "Hello i want to go.".Split(' ')[2];
//Returns the word "want"

string input = "Hello I want to go.";
string[] sentenceArray = input.Split(' ');
string required = sentenceArray[2];

Here's an example using Regex which gives you the index of each occurrence of "want":
string str = "Hello i want to go. Hello i want to go. Hello i want to go.";
Match match = Regex.Match(str, "want");
while(match.Success){
Console.WriteLine(string.Format("Index: {0}", match.Index));
match = match.NextMatch();
}

Nowhere does it say Regex...
string result = input.Split.Skip(2).Take(1).First()

it's work
public static string Between(this string src, string findfrom, string findto)
{
int start = src.IndexOf(findfrom);
int to = src.IndexOf(findto, start + findfrom.Length);
if (start < 0 || to < 0) return "";
string s = src.Substring(
start + findfrom.Length,
to - start - findfrom.Length);
return s;
}
and it can be called as
string respons = Between("Hello i want to go."," i "," to ");
it return want

How to split string using Substring

I have a string like '/Test1/Test2', and i need to take Test2 separated from the same. How can i do that in c# ?

Try this:
string toSplit= "/Test1/Test2";
toSplit.Split('/');
or
toSplit.Split(new [] {'/'}, System.StringSplitOptions.RemoveEmptyEntries);
to split, the latter will remove the empty string.
Adding .Last() will get you the last item.
e.g.
toSplit.Split('/').Last();

Use .Split().
string foo = "/Test1/Test2";
string extractedString = foo.Split('/').Last(); // Result Test2
This site have quite a few examples of splitting strings in C#. It's worth a read.

Using .Split and a little bit of LINQ, you could do the following
string str = "/Test1/Test2";
string desiredValue = str.Split('/').Last();
Otherwise you could do
string str = "/Test1/Test2";
string desiredValue = str;
if(str.Contains("/"))
desiredValue = str.Substring(str.LastIndexOf("/") + 1);
Thanks Binary Worrier, forgot that you'd want to drop the '/', darn fenceposts

string[] arr = string1.split('/');
string result = arr[arr.length - 1];

string [] split = words.Split('/');
This will give you an array split that will contain "", "Test1" and "Test2".

If you just want the Test2 portion, try this:
string fullTest = "/Test1/Test2";
string test2 = test.Split('/').ElementAt(1); //This will grab the second element.

string inputString = "/Test1/Test2";
string[] stringSeparators = new string[] { "/Test1/"};
string[] result;
result = inputString.Split(stringSeparators,
StringSplitOptions.RemoveEmptyEntries);
foreach (string s in result)
{
Console.Write("{0}",s);
}
OUTPUT : Test2

Format "12345678" to "1234-5678"

How to format a string of numbers "12345678" to "1234-5678".
string str = "12345678";
//I want to format it like below
res = "1234-5678";
Thanks

You can use string.Insert:
string res = "12345678".Insert(4, "-");
The parameters are the index to insert into and the string to insert.

In case you need to format numbers, you can use String.Format() method:
int test = 12345678;
string res = String.Format("{0:####-####}", test); // res == "1234-5678"

How I could understand your desirable format is: to insert a hyphen after first four symbols in the string. if so, then It is very simple:
res = str.Length > 4 ? string.Concat (str.Substring (0, 4), "-", str.Substring (4)) : str;
If your format is other, please descride it in details.

You can also use .Substring like so:
string str1 = str.Substring(0,4);
string str2 = str.Substring(4,4);
string res = str1 + "-" + str2;

I used Visual Basic Code
It is not hard to convert on C#
Dim str As String = "12345678"
Dim num As Long = CLng(str)
Dim strOut As String = Format(num, "####-####")

Remove 2 or more blank spaces from a string in c#..?

what is the efficient mechanism to remove 2 or more white spaces from a string leaving single white space.
I mean if string is "a____b" the output must be "a_b".

You can use a regular expression to replace multiple spaces:
s = Regex.Replace(s, " {2,}", " ");

Something like below maybe:
var b=a.Split(new char[] {' '}, StringSplitOptions.RemoveEmptyEntries);
var noMultipleSpaces = string.Join(" ",b);

string tempo = "this is a string with spaces";
RegexOptions options = RegexOptions.None;
Regex regex = new Regex(#"[ ]{2,}", options);
tempo = regex.Replace(tempo, #" ");

You Can user this method n pass your string value as argument
you have to add one namespace also using System.Text.RegularExpressions;
public static string RemoveMultipleWhiteSpace(string str)
{
// A.
// Create the Regex.
Regex r = new Regex(#"\s+");
// B.
// Remove multiple spaces.
string s3 = r.Replace(str, #" ");
return s3;
}