Code Question p179

bill.mccullen · January 1st, 2009, 05:42 PM

Hi,

Can anyone give me breakdown of the following code on page 179 please?

if (!string.IsNullOrEmpty (value))

I'm a bit rusty and am puzzled, particularly by the use of the NOT operator. Could you provide a 'plain English' or pseudo code explanation please? Does it check that the string Is Not Null or Not Empty by using the ! operator?

Imar · January 1st, 2009, 05:55 PM

Hi Bill,

Basically it says:

If the variable value is not empty and if the variable value is not an empty string

string.IsNullOrEmpty is a boolean method that returns true when the value you pass in is either null (Nothing in VB.NET) or an empty string ("" / String.Empty).

By reversing its outcome using the ! operator, the code that follows will only be executed when the value variable contains a value that is not empty, and not null; e.g. some string value.

So, it checks that the string is NOT null and NOT empty

Hope this helps,

Imar

bill.mccullen · January 1st, 2009, 06:56 PM

Many Thanks Imar.

Imar · January 2nd, 2009, 05:06 AM

You're welcome...

Imar