C#

Re: string.Empty vs ""

Xiaoth — Tue, 30 Sep 2008 07:22:57 GMT

As far as I'm concerned, it's a question of productivity vs. performance, not a question of performance or correctness alone. If you really want to sit there and type S-t-r-i-n-g-.-E-m-p-t-y, go right ahead. It's worth it if you have an awful lot of empty strings in loops. ;)

That said, I once created a macro (as a result of reading this thread, a couple years ago), that would detect when I typed "" and replace it with String.Empty. I removed it after a few weeks because it was so distracting and I never got use to the fugly presence of all that code ("String.Empty") for such a simple thing.

Re: string.Empty vs ""

TATWORTH — Sat, 27 Sep 2008 11:30:16 GMT

StyleCop requires string.Empty over an empty string. - Given its pedigree, I accept its advice in the matter.

Re: string.Empty vs ""

devbrat_ghosh — Fri, 26 Sep 2008 11:29:23 GMT

Thanks to all contributors. This question arise several times . I took Ryan reply as answer of my long lasting doubt.

Re: string.Empty vs ""

nberardi — Fri, 07 Apr 2006 14:38:06 GMT

bitmask:
KraGiE:
Since "" is actually a value type, it'll create that object anyways, but yeah. I tend to use String.Empty also.

Actually, since it is still a string, it's a reference type ;)

However strings are immutable, which in a high level over view means they act like a value type. In addition I also think the compiler checkes for other strings with the same signature to cut down on memory use. I could be wrong on the previous statement, however all that being said I am still an advocate of String.Empty because it is cleaner and on the off chance an empty string ever changes to "*" my programs are all set.

Re: string.Empty vs ""

StrongTypes — Fri, 07 Apr 2006 12:58:10 GMT

Xiaoth:
Why is it pointless? String.Empty is a whole lot more typing than "".
There is a performance difference but it's pretty minor.

1) I've read this too many times, but nobody has the research to proove it when they claim it.
2) The difference is really minor. I can see how this might be important in a large scale project, but other than that it's like comparing apples and oranges.

Ryan

Re: string.Empty vs ""

Xiaoth — Fri, 07 Apr 2006 08:51:20 GMT

StrongTypes:

This is a pointless debate in the developer world, but "" creates an object instance while String.Empty does not. I generally tend to use String.Empty over "".

HTH,
Ryan

Why is it pointless? String.Empty is a whole lot more typing than "".

There is a performance difference but it's pretty minor. In the tests below, the "" operations loop took up 15.85 to 15.88 seconds, while the String.Empty operations loop took up 15.82 to 15.87 seconds.

        private void button3_Click(object sender, EventArgs e)
        {
            DateTime dt = DateTime.Now;
            string s = "";
            for (int i = 0; i < 1000000000; i++)
            {
                if (s == "")
                {
                    s = "";
                }
            }
            TimeSpan ts = new TimeSpan(DateTime.Now.Ticks - dt.Ticks);
            textBox1.Text = ts.ToString();
        }

        private void button4_Click(object sender, EventArgs e)
        {
            DateTime dt = DateTime.Now;
            string s = String.Empty;
            for (int i = 0; i < 1000000000; i++)
            {
                if (s == String.Empty)
                {
                    s = String.Empty;
                }
            }
            TimeSpan ts = new TimeSpan(DateTime.Now.Ticks - dt.Ticks);
            textBox1.Text = ts.ToString();
        }

Re: string.Empty vs ""

KraGiE — Thu, 06 Apr 2006 22:34:51 GMT

what does int? have to do with ""? a nullable type doesn't dignify anything in regards to using "" in place of an ANSI SQL's null value.. int? x = DBNull.Value returns Error 2 Cannot implicitly convert type 'System.DBNull' to 'int?' So where are you going with this?

edited:
Caddre, did you read that blog? It talks about nullable types that was introduced to c#2.0. Meaning..

int xyz;

if (xyz != null) {
// this was not possible in previous versions of .net
}

It's to remove the need to explicitly set a value to value types.

Re: string.Empty vs ""

Caddre — Thu, 06 Apr 2006 19:16:44 GMT

I will not dignify that with an answer.

http://blogs.msdn.com/somasegar/archive/2005/08/11/450640.aspx

Re: string.Empty vs ""

KraGiE — Thu, 06 Apr 2006 18:40:48 GMT

Caddre:
Kay,
This is the beauty of these forums because when you tell other people they are confused about something for making a mistake you can make the same mistake, '''' is sometimes used by object developers to deal with ANSI SQL null because as the CLR team's head Brad Abrams said Strings are reference types that thinks they are value types. We are human.

Caddre, that is the beauty of the forums. The string being a reference type instead of value type is a common one, and it's something I did know. I just jumped the gun and typed before thinking. This is quite a bit different than being "confused".

Also, I believe ANSI Sql's Nulls are totally different from an empty string. Where in the world do people actually use "" to deal with ANSI SQL null? I always thought "object developers" had objects defined to map efficiently and correctly to other objects.. being that "" in ANSI SQL is completely different than "<null>"

Re: string.Empty vs ""

Caddre — Thu, 06 Apr 2006 18:29:06 GMT

Strings are Immutable that is the CS term for it. LOL And have a nice day.

Re: string.Empty vs ""

KraGiE — Thu, 06 Apr 2006 18:25:59 GMT

You're absolutely right. I'm actually blushing. haha It's just one of those things that basically creates a shallow copy when entering methods. It's one of those reference types that doesn't really pass around a reference, but rather creates a shallow copy so any changes in the called method doesn't refect the altered value in the calling method.

If that makes sense. :)

Re: string.Empty vs ""

Caddre — Thu, 06 Apr 2006 18:21:30 GMT

bitmask:

KraGiE:
Since "" is actually a value type, it'll create that object anyways, but yeah. I tend to use String.Empty also.

Actually, since it is still a string, it's a reference type ;)

Kay,

This is the beauty of these forums because when you tell other people they are confused about something for making a mistake you can make the same mistake, '''' is sometimes used by object developers to deal with ANSI SQL null because as the CLR team's head Brad Abrams said Strings are reference types that thinks they are value types. We are human.

Re: string.Empty vs ""

bitmask — Thu, 06 Apr 2006 15:26:07 GMT

KraGiE:
Since "" is actually a value type, it'll create that object anyways, but yeah. I tend to use String.Empty also.

Actually, since it is still a string, it's a reference type ;)

Re: string.Empty vs ""

KraGiE — Fri, 31 Mar 2006 20:58:58 GMT

Yeah. String.Empty is a read-only that returns "". Since "" is actually a value type, it'll create that object anyways, but yeah. I tend to use String.Empty also. I believe it's faster, but I really don't have the core internals to prove it.

Re: string.Empty vs ""

StrongTypes — Fri, 31 Mar 2006 14:53:37 GMT

This is a pointless debate in the developer world, but "" creates an object instance while String.Empty does not. I generally tend to use String.Empty over "".

HTH,
Ryan