Is string.IsNullOrEmpty same as String.IsNullOrEmpty?

Question

Look at the following code. Are they the same? Is there any difference? If yes what?

    string f = textBox5.Text;
    if (string.IsNullOrEmpty(f))
    {
        MessageBox.Show("string");
    }
    if (String.IsNullOrEmpty(f))
    {
        MessageBox.Show("String");
    }

Edit: Is a null or empty string test exactly the same as null or empty String test?

Why are people voting to reopen this? The duplicate answers the question exactly, or *all* uses of `string` and `String`, *which includes this type of usage*. — Servy, Oct 24 '13 at 16:53
As per this [_this existing question_](http://stackoverflow.com/questions/7074/whats-the-difference-between-string-and-string) `string` is merely an *alias* for `System.String` as is true for all of the other primitive types. Given this, both statements will call the exact same method so no, there is no difference. — User 12345678, Oct 24 '13 at 16:53
@FloodGravemind I *did* mark it as a duplicate. See below, "marked as duplicate by Servy [...]". I do have a problem with people inappropriately reopening a question that is correctly closed. Why shouldn't I be? Why should I ignore something like that? — Servy, Oct 24 '13 at 16:58

score 2 · Answer 1 · answered Oct 24 '13 at 16:45

2

string is just an alias for System.String, just like object is an alias for System.Object, so in short, they refer to exactly the same thing.

answered Oct 24 '13 at 16:45

Will Faithfull

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score 2 · Answer 2 · answered Oct 24 '13 at 16:45

2

Yes they are the same. string is just an alias to System.String.

answered Oct 24 '13 at 16:45

Reda

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score 2 · Accepted Answer · answered Oct 24 '13 at 16:45

2

As ByteBlast said - they are the same thing but string is a keyword (and alias) for String (which is a class). but remember, if you are porting over apps to WinRT, then String does not work - only string.

answered Oct 24 '13 at 16:45

Ahmed ilyas

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Is string.IsNullOrEmpty same as String.IsNullOrEmpty?

3 Answers3