Replace multiple characters in a C# string

Is there a better way to replace strings?

I am surprised that Replace does not take in a character array or string array. I guess that I could write my own extension but I was curious if there is a better built in way to do the following? Notice the last Replace is a string not a character.

myString.Replace(';', '\n').Replace(',', '\n').Replace('\r', '\n').Replace('\t', '\n').Replace(' ', '\n').Replace("\n\n", "\n");

Solution 1:

You can use a replace regular expression.

s/[;,\t\r ]|[\n]{2}/\n/g

• s/ at the beginning means a search
• The characters between [ and ] are the characters to search for (in any order)
• The second / delimits the search-for text and the replace text

In English, this reads:

"Search for ; or , or \t or \r or (space) or exactly two sequential \n and replace it with \n"

In C#, you could do the following: (after importing System.Text.RegularExpressions)

Regex pattern = new Regex("[;,\t\r ]|[\n]{2}");
pattern.Replace(myString, "\n");

Solution 2:

If you are feeling particularly clever and don't want to use Regex:

char[] separators = new char[]{' ',';',',','\r','\t','\n'};

string s = "this;is,\ra\t\n\n\ntest";
string[] temp = s.Split(separators, StringSplitOptions.RemoveEmptyEntries);
s = String.Join("\n", temp);

You could wrap this in an extension method with little effort as well.

Edit: Or just wait 2 minutes and I'll end up writing it anyway :)

public static class ExtensionMethods
{
   public static string Replace(this string s, char[] separators, string newVal)
   {
       string[] temp;

       temp = s.Split(separators, StringSplitOptions.RemoveEmptyEntries);
       return String.Join( newVal, temp );
   }
}

And voila...

char[] separators = new char[]{' ',';',',','\r','\t','\n'};
string s = "this;is,\ra\t\n\n\ntest";

s = s.Replace(separators, "\n");

Solution 3:

You could use Linq's Aggregate function:

string s = "the\nquick\tbrown\rdog,jumped;over the lazy fox.";
char[] chars = new char[] { ' ', ';', ',', '\r', '\t', '\n' };
string snew = chars.Aggregate(s, (c1, c2) => c1.Replace(c2, '\n'));

Here's the extension method:

public static string ReplaceAll(this string seed, char[] chars, char replacementCharacter)
{
    return chars.Aggregate(seed, (str, cItem) => str.Replace(cItem, replacementCharacter));
}

Extension method usage example:

string snew = s.ReplaceAll(chars, '\n');