trim all strings in an array

Question

I have a string that comes in like:

string email = "a@a.com, b@b.com, c@c.com";

I want to split it into an array of strings

If I do this:

string[] emails = email.Split(',');

I get spaces in front of each email address (after the first one):

emails[0] = "a@a.com"
emails[1] = " b@b.com"
emails[2] = " c@c.com"

What is the best way to get this (either a better way to parse or a way to trim all strings in an array)?

emails[0] = "a@a.com"
emails[1] = "b@b.com"
emails[2] = "c@c.com"

Answer 1

emails.Split(',').Select(email => email.Trim()).ToArray()

Answer 2

You could also replace all occurrences of spaces, and so avoid the foreach loop:

string email = "a@a.com, b@b.com, c@c.com";    
string[] emails = email.Replace(" ", "").Split(',');

Answer 3

Either one of the following would work. I'd recommend the first since it more accurately expresses the joining string.

string[] emails = email.Split(new string[] { ", " }, StringSplitOptions.None);
string[] emails = email.Split(new char[] { ' ', ',' }, StringSplitOptions.RemoveEmptyEntries);

Answer 4

You can use Trim():

string email = "a@a.com, b@b.com, c@c.com";
string[] emails = email.Split(',');
emails = (from e in emails
          select e.Trim()).ToArray();

Answer 5

Use Regex.Split to avoid trimming

var emails = Regex.Split(email, @",\s*");

Answer 6

You can use a one line solution like this:

string[] emails = text.Split(',', StringSplitOptions.RemoveEmptyEntries);
Array.ForEach<string>(emails, x => emails[Array.IndexOf<string>(emails, x)] = x.Trim());

Answer 7

.NET 5 has arrived and with it, a modern solution to this problem:

string[] emails = email.Split(',', StringSplitOptions.TrimEntries);

Answer 8

If you just need to manipulate the entries, without returning the array:

string[] emails = text.Split(',');
Array.ForEach(emails, e => e.Trim());

Answer 9

Alternatively, you can split using a regular expression of the form:

\s*,\s*

i.e.

string[] emails = Regex.Split(email, @"\s*,\s*");

It will consume the surrounding spaces directly.

Regular expressions are usually a performance hit, but the example you gave indicates that this is something you plan to do once in your code for a short array.

Answer 10

The answer from Bryan Watts is elegant and simple. He implicitly refers to the array of strings created by the Split().

Also note its extensibility if you are reading a file, and want to massage the data while building an array.

string sFileA = @"C:\Documents and Settings\FileA.txt";
string sFileB = @"C:\Documents and Settings\FileB.txt";

// Trim extraneous spaces from the first file's data
string[] fileAData = (from line in File.ReadAllLines( sFileA )
                      select line.Trim()).ToArray();

// Strip a second unneeded column from the second file's data
string[] fileBData = (from line in File.ReadAllLines( sFileB )
                      select line.Substring( 0, 21 ).Trim()).ToArray();

Of course, you can use the Linq => notation if you prefer.

string[] fileBData = File.ReadAllLines( sFileB ).Select( line =>
                             line.Substring( 0, 21 ).Trim()).ToArray();

Although my answer should have been posted as a comment, I don't have enough reputation points to comment yet. But I found this discussion invaluable in figuring out how to massage data while using ReadAllLines().

Answer 11

Use String.Trim in a foreach loop, or if you are using .NET 3.5+ a LINQ statement.

Answer 12

In .NET 5, they added StringSplitOptions.TrimEntries.

You can use it like

string[] emails = email.Split(',', StringSplitOptions.TrimEntries);

Which will give you

emails[0] = "a@a.com"
emails[1] = "b@b.com"
emails[2] = "c@c.com"