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Checking if an object is null in C#
... List<Object>();
Even better: since it's a field, make it private. And if there's nothing preventing you, make it also readonly. Just good practice.
Aside
The correct way to check for nullity is if(data != null). This kind of check is ubiquitous for reference types; even Nullable<T> ...
How to initialize a struct in accordance with C programming language standards
I want to initialize a struct element, split in declaration and initialization. This is what I have:
15 Answers
...
Update value of a nested dictionary of varying depth
...ight general idea, i.e. a recursive solution, but somewhat peculiar coding and at least one bug. I'd recommend, instead:
Python 2:
import collections
def update(d, u):
for k, v in u.iteritems():
if isinstance(v, collections.Mapping):
d[k] = update(d.get(k, {}), v)
...
Position: absolute and parent height?
I have some containers and their children are only absolute / relatively positioned. How to set containers height so their children will be inside of them?
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(413) Request Entity Too Large | uploadReadAheadSize
...ystem with IIS 7.5.
One of the service methods has an 'object' as argument and I'm trying to send a byte[] which contains a picture.
As long as the file size of this picture is less then approx. 48KB, all goes well. But if I'm trying to upload a larger picture, the WCF service returns an error: (41...
Installing multiple instances of the same windows service on a server
So we've produced a windows service to feed data to our client application and everything is going great. The client has come up with a fun configuration request that requires two instances of this service running on the same server and configured to point at separate databases.
...
How to include another XHTML in XHTML using JSF 2.0 Facelets?
....xhtml. Do note that you don't need to repeat <html>, <h:head> and <h:body> inside the include file as that would otherwise result in invalid HTML.
You can use a dynamic EL expression in <ui:include src>. See also How to ajax-refresh dynamic include content by navigation menu...
How do I uninstall a Windows service if the files do not exist anymore?
...xe) included in the Resource Kit.
(included with Windows 7/8)
Open a Command Prompt and enter
sc delete <service-name>
Tool help snippet follows:
DESCRIPTION:
SC is a command line program used for communicating with the
NT Service Controller and services.
delete---------...
NullPointerException accessing views in onCreate()
...d-generated code.
The view is in the fragment layout (fragment_main.xml) and not in the activity layout (activity_main.xml). onCreate() is too early in the lifecycle to find it in the activity view hierarchy, and a null is returned. Invoking a method on null causes the NPE.
The preferred solution...
initialize a numpy array
Is there way to initialize a numpy array of a shape and add to it? I will explain what I need with a list example. If I want to create a list of objects generated in a loop, I can do:
...