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Why is there a difference in checking null against a value in VB.NET and C#?
...I don't know yet". Then the comparison of 5 to "I don't know yet". is naturally "I don't know yet"; ie NULL. This has the additional advantage of mirroring the behaviour of NULL in (most if not all) SQL databases. This is also a more standard (than C#'s) interpretation of three-valued logic, as expl...
Why Does OAuth v2 Have Both Access and Refresh Tokens?
... token in order to gain an access token.
Having said that, because every call to both the authorization server and the resource server is done over SSL - including the original client id and secret when they request the access/refresh tokens - I am unsure as to how the access token is any more "com...
Why .NET String is immutable? [duplicate]
As we all know, String is immutable. What are the reasons for String being immutable and the introduction of StringBuilder class as mutable?
...
Output array to CSV in Ruby
...enerate_line(row) }.join("")
#=> "a1,a2,a3\nb1,b2,b3\nc1,c2,c3\n"
Do all of the above and save to a csv, in one line.
File.open("ss.csv", "w") {|f| f.write(rows.inject([]) { |csv, row| csv << CSV.generate_line(row) }.join(""))}
NOTE:
To convert an active record database to csv would...
What is the difference between const and readonly in C#?
...time of a definition for a const VS readonly values can be computed dynamically but need to be assigned before the constructor exits.. after that it is frozen.
'const's are implicitly static. You use a ClassName.ConstantName notation to access them.
There is a subtle difference. Consider a class d...
Difference between window.location.href=window.location.href and window.location.reload()
...
Also note that location.reload() will also force reload all static content (much like a ctrl+f5 style hard refresh) whereas setting location.href back to href (or pathname or URL) does not, which could be a significant (and unnecessary) difference in load time on some pages.
...
MySQL load NULL values from CSV data
...one, two, three, @vfour, five)
SET four = NULLIF(@vfour,'')
;
If they're all possibly empty, then you'd read them all into variables and have multiple SET statements, like this:
LOAD DATA INFILE '/tmp/testdata.txt'
INTO TABLE moo
FIELDS TERMINATED BY ","
LINES TERMINATED BY "\n"
(@vone, @vtwo, @v...
Bootstrap full-width text-input within inline-form
...a
width on the form controls used within.
The default width of 100% as all form elements gets when they got the class form-control didn't apply if you use the form-inline class on your form.
You could take a look at the bootstrap.css (or .less, whatever you prefer) where you will find this part...
Free space in a CMD shell
...unt of free diskspace of a disk or a folder in a CMD
without having to install some thirdparty applications?
9 Answers
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Haversine Formula in Python (Bearing and Distance between two GPS points)
...fy math.pi, math.sin etc. With from math import * you get direct access to all the module contents. Check out "namespaces" in a python tutorial (such as docs.python.org/tutorial/modules.html)
– Michael Dunn
Feb 6 '11 at 21:20
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