Can I convert a C# string value to an escaped string literal?

In C#, can I convert a string value to a string literal, the way I would see it in code? I would like to replace tabs, newlines, etc. with their escape sequences.

If this code:

Console.WriteLine(someString);

produces:

Hello
World!

I want this code:

Console.WriteLine(ToLiteral(someString));

to produce:

\tHello\r\n\tWorld!\r\n

Solution 1:

I found this:

private static string ToLiteral(string input)
{
    using (var writer = new StringWriter())
    {
        using (var provider = CodeDomProvider.CreateProvider("CSharp"))
        {
            provider.GenerateCodeFromExpression(new CodePrimitiveExpression(input), writer, null);
            return writer.ToString();
        }
    }
}

This code:

var input = "\tHello\r\n\tWorld!";
Console.WriteLine(input);
Console.WriteLine(ToLiteral(input));

Produces:

    Hello
    World!
"\tHello\r\n\tWorld!"

Solution 2:

Use Regex.Escape(String):

Regex.Escape escapes a minimal set of characters (, *, +, ?, |, {, [, (,), ^, $,., #, and white space) by replacing them with their escape codes.

Solution 3:

A more structured approach, including all escape sequences for strings and chars, is:

It doesn't replace Unicode characters with their literal equivalent. It doesn't cook eggs, either.

public class ReplaceString
{
    static readonly IDictionary<string, string> m_replaceDict
        = new Dictionary<string, string>();

    const string ms_regexEscapes = @"[\a\b\f\n\r\t\v\\""]";

    public static string StringLiteral(string i_string)
    {
        return Regex.Replace(i_string, ms_regexEscapes, match);
    }

    public static string CharLiteral(char c)
    {
        return c == '\'' ? @"'\''" : string.Format("'{0}'", c);
    }

    private static string match(Match m)
    {
        string match = m.ToString();
        if (m_replaceDict.ContainsKey(match))
        {
            return m_replaceDict[match];
        }

        throw new NotSupportedException();
    }

    static ReplaceString()
    {
        m_replaceDict.Add("\a", @"\a");
        m_replaceDict.Add("\b", @"\b");
        m_replaceDict.Add("\f", @"\f");
        m_replaceDict.Add("\n", @"\n");
        m_replaceDict.Add("\r", @"\r");
        m_replaceDict.Add("\t", @"\t");
        m_replaceDict.Add("\v", @"\v");

        m_replaceDict.Add("\\", @"\\");
        m_replaceDict.Add("\0", @"\0");

        //The SO parser gets fooled by the verbatim version
        //of the string to replace - @"\"""
        //so use the 'regular' version
        m_replaceDict.Add("\"", "\\\"");
    }

    static void Main(string[] args){

        string s = "here's a \"\n\tstring\" to test";
        Console.WriteLine(ReplaceString.StringLiteral(s));
        Console.WriteLine(ReplaceString.CharLiteral('c'));
        Console.WriteLine(ReplaceString.CharLiteral('\''));

    }
}