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C# elegant way to check if a property's property is null
...rom b in a.PropertyB
from c in b.PropertyC
select c.Value;
This returns null, if any of the nullable properties are null; otherwise, the value of Value.
class A { public B PropertyB { get; set; } }
class B { public C PropertyC { get; set; } }
class C { public strin...
When someone writes a new programming language, what do they write it IN?
...
If you select an unsuited language for a task, it's your own fault. This can happen for any project, not just compilers/interpreters.
– ziggystar
Oct 27 '09 at 11:09
...
What is the difference between Strategy pattern and Dependency Injection?
...rn) is a particular software
design pattern, whereby algorithms can
be selected at runtime.
The strategy pattern is intended to
provide a means to define a family of
algorithms, encapsulate each one as an
object, and make them interchangeable.
The strategy pattern lets the
algorit...
Visual Studio replace tab with 4 spaces?
... spaces in Visual Studio 2010 instead of going to Edit->Advanced->Untabify Selected Lines?
5 Answers
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Swift compiler error: “non-modular header inside framework module”
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Is your header public?
Select the header file in the project explorer. Then in the section on the right in xcode, you'll notice there is a dropdown next to the target. Change that from "project" to "public". This worked for me.
...
Reload django object from database
...k=self.pk)
# You may want to clear out the old dict first or perform a selective merge
self.__dict__.update(new_self.__dict__)
# Use it like this
bar.foo = foo
assert bar.foo.pk is None
foo.save()
foo.reload()
assert bar.foo is foo and bar.foo.pk is not None
...
Use a normal link to submit a form
...
just for the record: you should select the appropriate input element using CSS selectors without attaching a class to the HTML element.
– Erik Kaplun
Jul 6 '14 at 13:37
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Interface vs Abstract Class (general OO)
...e strategy pattern. A Pilot would have a collection of certifications, and select the correct one at runtime. The certifications would be coded as behaviors that would implement the IFlyPlane interface, with TakeOff, Land, Eject methods.
– Michael Blackburn
Dec...
Bootstrap 3 Navbar Collapse
...rs for /css, /js, /fonts. Customizing it just gives the compiled files you selected.
– jmbertucci
Sep 16 '13 at 14:41
...
PHP Redirect with POST data
... the output of a
POST-activated script to redirect the
user agent to a selected resource. The
new URI is not a substitute reference
for the originally requested resource.
The 303 response MUST NOT be cached,
but the response to the second
(redirected) request might be
cacheable.
Th...