Convert ASCII numbers between curly brackets in multiple places in a string to their char equivalent

I have columns in a database table storing strings where SOME non-alphanumeric characters are stored as ASCII integers between curly braces.

Example: C:\Folder#3\File_1_@.TXT is stored in the DB as C:\Folder{35}3\File{95}1{95}{64}.TXT

I want to write a function where I can pass a string as a parameter and then check if it contains characters # _ ? % @

If it does, I want to treat the string and convert these ASCII to back to their char equivalents.

In brief, if I pass "C:\Folder{35}3\File{95}1{95}{64}.TXT" as the input string, I want "C:\Folder#3\File_1_@.TXT" as the output.

I've been trying to use System.Text.RegularExpressions to solve this but not getting anywhere.

Any help is appreciated.

you just use the lambda expression in Regex.Replace:

        var input = @"C:\Folder{35}3\File{95}1{95}{64}.TXT";
        var output = Regex.Replace(input, @"\{(\d+)\}", m => ((char)int.Parse(m.Groups[1].Value)).ToString());

result for output:

C:\Folder#3\File_1_@.TXT

the function ((char)int.Parse(m.Groups[1].Value)).ToString()) get the character from the ascii value (string here and not int)

I hope this helps.

String address = "C:\\Folder{35}3\\File{95}1{95}{64}.TXT";

while (address.Contains("{")) {
	Int32 start = address.IndexOf("{");
	Int32 end = address.IndexOf("}");

	String subString = address.Substring(start, end - start + 1);

	Char @char =  (Char)Int32.Parse((address.Substring(start + 1, end - start - 1)));

	address = address.Remove(start, end - start + 1);
	address = address.Insert(start, @char.ToString());

	//or
	//address = address.Replace(subString, @char.ToString());
}

Console.WriteLine(address);

I think you were in a good way to solve it.
I can suggest you to use :

public static string Replace (string input, string pattern, System.Text.RegularExpressions.MatchEvaluator evaluator, System.Text.RegularExpressions.RegexOptions options);

where your pattern could be a regex : {.}|{..}|{...} which match all characters (3 characters maximum) inside your braces
And your match evaluator could be just an ascii to char converter.

See the microsoft documentation below:

system-text-regularexpressions-regex-replace