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Capture substring within delimiters and excluding characters using regex

How could a regex pattern look like to capture a substring between 2 delimiters, but excluding some characters (if any) after first delimiter and before last delimiter (if any)?
The input string looks for instance like this:
var input = #"Not relevant {
#AddInfoStart Comment:String:=""This is a comment"";
AdditionalInfo:String:=""This is some additional info"" ;
# } also not relevant";
The capture should contain the substring between "{" and "}", but excluding any spaces, newlines and "#AddInfoStart" string after start delimiter "{" (just if any of them present), and also excluding any spaces, newlines and ";" and "#" characters before end delimiter "}" (also if any of them present).
The captured string should look like this
Comment:String:=""This is a comment"";
AdditionalInfo:String:=""This is some additional info""
It is possible that there are blanks before or after the ":" and ":=" internal delimiters, and also that the value after ":=" is not always marked as a string, for instance something like:
{ Val1 : Real := 1.7 }
For arrays is used the following syntax:
arr1 : ARRAY [1..5] OF INT := [2,5,44,555,11];
arr2 : ARRAY [1..3] OF REAL

This is my solution:
Remove the content outside the brackets
Use a regular expression to get the values inside the brackets
Code:
var input = #"Not relevant {
#AddInfoStart Comment:String:=""This is a comment"";
Val1 : Real := 1.7
AdditionalInfo:String:=""This is some additional info"" ;
# } also not relevant";
// remove content outside brackets
input = Regex.Replace(input, #".*\{", string.Empty);
input = Regex.Replace(input, #"\}.*", string.Empty);
string property = #"(\w+)";
string separator = #"\s*:\s*"; // ":" with or without whitespace
string type = #"(\w+)";
string equals = #"\s*:=\s*"; // ":=" with or without whitespace
string text = #"""?(.*?)"""; // value between ""
string number = #"(\d+(\.\d+)?)"; // number like 123 or with a . separator such as 1.45
string value = $"({text}|{number})"; // value can be a string or number
string pattern = $"{property}{separator}{type}{equals}{value}";
var result = Regex.Matches(input, pattern)
.Cast<Match>()
.Select(match => new
{
FullMatch = match.Groups[0].Value, // full match is always the 1st group
Property = match.Groups[1].Value,
Type = match.Groups[2].Value,
Value = match.Groups[3].Value
})
.ToList();

Adding whitespaces to a string in C#

I'm getting a string as a parameter.
Every string should take 30 characters and after I check its length I want to add whitespaces to the end of the string.
E.g. if the passed string is 25 characters long, I want to add 5 more whitespaces.
The question is, how do I add whitespaces to a string?

You can use String.PadRight for this.
Returns a new string that left-aligns the characters in this string by padding them with spaces on the right, for a specified total length.
For example:
string paddedParam = param.PadRight(30);

You can use String.PadRight method for this;
Returns a new string of a specified length in which the end of the
current string is padded with spaces or with a specified Unicode
character.
string s = "cat".PadRight(10);
string s2 = "poodle".PadRight(10);
Console.Write(s);
Console.WriteLine("feline");
Console.Write(s2);
Console.WriteLine("canine");
Output will be;
cat feline
poodle canine
Here is a DEMO.
PadRight adds spaces to the right of strings. It makes text easier to
read or store in databases. Padding a string adds whitespace or other
characters to the beginning or end. PadRight supports any character
for padding, not just a space.

Use String.PadRight which will space out a string so it is as long as the int provided.
var str = "hello world";
var padded = str.PadRight(30);
// padded = "hello world "

you can use Padding in C#
eg
string s = "Example";
s=s.PadRight(30);
I hope It will resolve your problem.

Search for a newline Character C#.net

How do i search a string for a newline character? Both of the below seem to be returning -1....!
theJ = line.IndexOf(Environment.NewLine);
OR
theJ = line.IndexOf('\n');
The string it's searching is "yo\n"
the string i'm parsing contains this "printf("yo\n");"
the string i see contained during the comparison is this: "\tprintf(\"yo\n\");"

"yo\n" // output as "yo" + newline
"yo\n".IndexOf('\n') // returns 2
"yo\\n" // output as "yo\n"
"yo\\n".IndexOf('\n') // returns -1
Are you sure you're searching yo\n and not yo\\n?
Edit
Based on your update, I can see that I guessed correctly. If your string says:
printf("yo\n");
... then this does not contain a newline character. If it did, it would look like this:
printf("yo
");
What it actually has is an escaped newline character, or in other words, a backslash character followed by an 'n'. That's why the string you're seeing when you debug is "\tprintf(\"yo\\n\");". If you want to find this character combination, you can use:
line.IndexOf("\\n")
For example:
"\tprintf(\"yo\\n\");" // output as " printf("yo\n");"
"\tprintf(\"yo\\n\");".IndexOf("\\n") // returns 11

Looks like your line does not contain a newline.
If you are using File.ReadAllLines or string.Split on newline, then each line in the returned array will not contain the newline. If you are using StreamReader or one of the classes inheriting from it, the ReadLine method will return the string without the newline.
string lotsOfLines = #"one
two
three";
string[] lines = lotsOfLines.Split('\n');
foreach(string line in lines)
{
Console.WriteLine(line.IndexOf('\n'); // prints -1 three times
}

That should work although in Windows you'll have to search for '\r\n'.
-1 simply means that no enter was found.

It depends what you are trying to do. Both may no be identical on some platforms.
Environment.NewLine returns:
A string containing "\r\n" for non-Unix platforms, or a string
containing "\n" for Unix platforms.
Also:
If you want to search for the \n char (new line on Unix), use \n
If you want to search for the \r\n chars (new line on Windows), use \r\n
If your search depend on the current platform, use Environment.NewLine
If it returns -1 in both cases you mentioned, then you don't have a new line in your string.

When I was in college and I did a WebForms aplication to order referencies.
And the line break/carriage return it was what I used to break a referense.
//Text from TextBox
var text = textBox1.Text;
//Create an array with the text between the carriage returns
var references = text.Split(new string[] { "\r\n", "\r" }, StringSplitOptions.RemoveEmptyEntries);
//Simple OrderBy(Alphabetical)
var ordered = references.ToList<string>().OrderBy(ff => ff);
//Return the entry text ordered alphabetical em with a carriage return between every result
var valueToReturn = String.Join(Environment.NewLine, ordered);
textBox1.Text = valueToReturn;

The Environment.NewLine is not the same as \n. It is a CRLF (\r\n). However, I did try with the \n using IndexOf and my test did find the value. Are you sure what you're searching for is a \n rather than a \r? View your text in hexadecimal format and see what the hex value is.

Unquote string in C#

I have a data file in INI file like format that needs to be read by both some C code and some C# code. The C code expects string values to be surrounded in quotes. The C# equivalent code is using some underlying class or something I have no control over, but basically it includes the quotes as part of the output string. I.e. data file contents of
MY_VAL="Hello World!"
gives me
"Hello World!"
in my C# string, when I really need it to contain
Hello World!
How do I conditionally (on having first and last character being a ") remove the quotes and get the string contents that I want.

On your string use Trim with the " as char:
.Trim('"')

I usually call String.Trim() for that purpose:
string source = "\"Hello World!\"";
string unquoted = source.Trim('"');

My implementation сheck that quotes are from both sides
public string UnquoteString(string str)
{
if (String.IsNullOrEmpty(str))
return str;
int length = str.Length;
if (length > 1 && str[0] == '\"' && str[length - 1] == '\"')
str = str.Substring(1, length - 2);
return str;
}

Just take the returned string and do a Trim('"');

Being obsessive, here (that's me; no comment about you), you may want to consider
.Trim(' ').Trim('"').Trim(' ')
so that any, bounding spaces outside of the quoted string are trimmed, then the quotation marks are stripped and, finally, any, bounding spaces for the contained string are removed.
If you want to retain contained, bounding white space, omit the final .Trim(' ').
Should there be embedded spaces and/or quotation marks, they will be preserved. Chances are, such are desired and should not be deleted.
Do some study as to what a no argument Trim() does to things like form feed and/or tabulation characters, bounding and embedded. It could be that one and/or the other Trim(' ') should be just Trim().

If you know there will always be " at the end and beginning, this would be the fastest way.
s = s.Substring(1, s.Length - 2);

Use string replace function or trim function.
If you just want to remove first and last quotes use substring function.
string myworld = "\"Hello World!\"";
string start = myworld.Substring(1, (myworld.Length - 2));

I would suggest using the replace() method.
string str = "\"HelloWorld\"";
string result = str.replace("\"", string.Empty);

What you are trying to do is often called "stripping" or "unquoting". Usually, when the value is quoted that means not only that it is surrounded by quotation characters (like " in this case) but also that it may or may not contain special characters to include quotation character itself inside quoted text.
In short, you should consider using something like:
string s = #"""Hey ""Mikey""!";
s = s.Trim('"').Replace(#"""""", #"""");
Or when using apostrophe mark:
string s = #"'Hey ''Mikey''!";
s = s.Trim('\'').Replace("''", #"'");
Also, sometimes values that don't need quotation at all (i.e. contains no whitespace) may not need to be quoted anyway. That's the reason checking for quotation characters before trimming is reasonable.
Consider creating a helper function that will do this job in a preferable way as in the example below.
public static string StripQuotes(string text, char quote, string unescape)a
{
string with = quote.ToString();
if (quote != '\0')
{
// check if text contains quote character at all
if (text.Length >= 2 && text.StartsWith(with) && text.EndsWith(with))
{
text = text.Trim(quote);
}
}
if (!string.IsNullOrEmpty(unescape))
{
text = text.Replace(unescape, with);
}
return text;
}
using System;
public class Program
{
public static void Main()
{
string text = #"""Hello World!""";
Console.WriteLine(text);
// That will do the job
// Output: Hello World!
string strippedText = text.Trim('"');
Console.WriteLine(strippedText);
string escapedText = #"""My name is \""Bond\"".""";
Console.WriteLine(escapedText);
// That will *NOT* do the job to good
// Output: My name is \"Bond\".
string strippedEscapedText = escapedText.Trim('"');
Console.WriteLine(strippedEscapedText);
// Allow to use \" inside quoted text
// Output: My name is "Bond".
string strippedEscapedText2 = escapedText.Trim('"').Replace(#"\""", #"""");
Console.WriteLine(strippedEscapedText2);
// Create a function that will check texts for having or not
// having citation marks and unescapes text if needed.
string t1 = #"""My name is \""Bond\"".""";
// Output: "My name is \"Bond\"."
Console.WriteLine(t1);
// Output: My name is "Bond".
Console.WriteLine(StripQuotes(t1, '"', #"\"""));
string t2 = #"""My name is """"Bond"""".""";
// Output: "My name is ""Bond""."
Console.WriteLine(t2);
// Output: My name is "Bond".
Console.WriteLine(StripQuotes(t2, '"', #""""""));
}
}
https://dotnetfiddle.net/TMLWHO

Here's my solution as extension method:
public static class StringExtensions
{
public static string UnquoteString(this string inputString) => inputString.TrimStart('"').TrimEnd('"');
}
It's just trimming at the start an the end...

How to remove leading and trailing spaces from a string

I have the following input:
string txt = " i am a string "
I want to remove space from start of starting and end from a string.
The result should be: "i am a string"
How can I do this in c#?

String.Trim
Removes all leading and trailing white-space characters from the current String object.
Usage:
txt = txt.Trim();
If this isn't working then it highly likely that the "spaces" aren't spaces but some other non printing or white space character, possibly tabs. In this case you need to use the String.Trim method which takes an array of characters:
char[] charsToTrim = { ' ', '\t' };
string result = txt.Trim(charsToTrim);
Source
You can add to this list as and when you come across more space like characters that are in your input data. Storing this list of characters in your database or configuration file would also mean that you don't have to rebuild your application each time you come across a new character to check for.
NOTE
As of .NET 4 .Trim() removes any character that Char.IsWhiteSpace returns true for so it should work for most cases you come across. Given this, it's probably not a good idea to replace this call with the one that takes a list of characters you have to maintain.
It would be better to call the default .Trim() and then call the method with your list of characters.

You can use:
String.TrimStart - Removes all leading occurrences of a set of characters specified in an array from the current String object.
String.TrimEnd - Removes all trailing occurrences of a set of characters specified in an array from the current String object.
String.Trim - combination of the two functions above
Usage:
string txt = " i am a string ";
char[] charsToTrim = { ' ' };
txt = txt.Trim(charsToTrim)); // txt = "i am a string"
EDIT:
txt = txt.Replace(" ", ""); // txt = "iamastring"

I really don't understand some of the hoops the other answers are jumping through.
var myString = " this is my String ";
var newstring = myString.Trim(); // results in "this is my String"
var noSpaceString = myString.Replace(" ", ""); // results in "thisismyString";
It's not rocket science.

txt = txt.Trim();

Or you can split your string to string array, splitting by space and then add every item of string array to empty string.
May be this is not the best and fastest method, but you can try, if other answer aren't what you whant.

text.Trim() is to be used
string txt = " i am a string ";
txt = txt.Trim();

Use the Trim method.

static void Main()
{
// A.
// Example strings with multiple whitespaces.
string s1 = "He saw a cute\tdog.";
string s2 = "There\n\twas another sentence.";
// B.
// Create the Regex.
Regex r = new Regex(#"\s+");
// C.
// Strip multiple spaces.
string s3 = r.Replace(s1, #" ");
Console.WriteLine(s3);
// D.
// Strip multiple spaces.
string s4 = r.Replace(s2, #" ");
Console.WriteLine(s4);
Console.ReadLine();
}
OUTPUT:
He saw a cute dog.
There was another sentence.
He saw a cute dog.

You Can Use
string txt = " i am a string ";
txt = txt.TrimStart().TrimEnd();
Output is "i am a string"