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javascript check for not null
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Try to check with 'null'
if ('null' != val)
For an explanation of when and why this works, see the details below.
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LINQ to SQL - Left Outer Join with multiple join conditions
...ull || c.Displaythrudate > date)
// Content is NOT draft, and IS published
&& c.Isdraft == "N" && c.Publishedon != null
orderby c.Sortorder ascending, c.Heading ascending
select c;
// Get the content specific to ...
How do you create nested dict in Python?
I have 2 CSV files: 'Data' and 'Mapping':
4 Answers
4
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How to change Vagrant 'default' machine name?
... of them to see exactly what they do.
I'm using VirtualBox 4.2.16-r86992 and Vagrant 1.3.3.
I created a directory called nametest and ran
vagrant init precise64 http://files.vagrantup.com/precise64.box
to generate a default Vagrantfile. Then I opened the VirtualBox GUI so I could see what na...
Enable 'xp_cmdshell' SQL Server
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Works really, well simple and effective!
– indofraiser
Nov 9 '15 at 10:38
2
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Export to CSV via PHP
.... is there a way I can export what I have from the database to a CSV file (and text file [if possible]) via PHP?
7 Answers
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Passport.js - Error: failed to serialize user into session
I got a problem with the Passport.js module and Express.js.
6 Answers
6
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Method call if not null in C#
...ke();
or:
obj?.SomeMethod();
The ?. is the null-propagating operator, and will cause the .Invoke() to be short-circuited when the operand is null. The operand is only accessed once, so there is no risk of the "value changes between check and invoke" problem.
===
Prior to C# 6, no: there is no...
How to get awaitable Thread.Sleep?
...ds.
You should instead use Task.Delay which doesn't require a new thread, and was designed precisely for this purpose:
// Execution of the async method will continue one second later, but without
// blocking.
await Task.Delay(1000);
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How to loop through a directory recursively to delete files with certain extensions
I need to loop through a directory recursively and remove all files with extension .pdf and .doc . I'm managing to loop through a directory recursively but not managing to filter the files with the above mentioned file extensions.
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