How to remove all white space from the beginning or end of a string?

Question

How can I remove all white space from the beginning and end of a string?

Like so:

"hello" returns "hello"
"hello " returns "hello"
" hello " returns "hello"
" hello world " returns "hello world"

Solution 1

String.Trim() returns a string which equals the input string with all white-spaces trimmed from start and end:

"   A String   ".Trim() -> "A String"

String.TrimStart() returns a string with white-spaces trimmed from the start:

"   A String   ".TrimStart() -> "A String   "

String.TrimEnd() returns a string with white-spaces trimmed from the end:

"   A String   ".TrimEnd() -> "   A String"

None of the methods modify the original string object.

(In some implementations at least, if there are no white-spaces to be trimmed, you get back the same string object you started with:

csharp> string a = "a"; csharp> string trimmed = a.Trim(); csharp> (object) a == (object) trimmed; returns true

I don't know whether this is guaranteed by the language.)

Solution 2

take a look at Trim() which returns a new string with whitespace removed from the beginning and end of the string it is called on.

Solution 3

string a = "   Hello   ";
string trimmed = a.Trim();

trimmed is now "Hello"

Solution 4

use the String.Trim() function.

string foo = "   hello ";
string bar = foo.Trim();

Console.WriteLine(bar); // writes "hello"

Solution 5

Use String.Trim method.

View more solutions

Comments

[Hi-Angel]

⁺¹ for the MS definition of whitespace. I met a weird behavior that .TrimEnd() doesn't work (for non-breaking space character), but in the end is just that the character not listed in documentation.

[Admin]

There are numerous ways to trim strings, and quite a few are bench-marked. Still, I like .Trim() as being the quickest to write and easiest to read.

[Nash Carp]

Maybe it is usefull to know this: If you have multiply lines like in a TextArea. And you press the enter key, you get something like: " A String \r\n " .Trim() does recognize this as a space too.

[huha]

@NashCarp: That´s because \r and \n are also whitespace characters