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is vs typeof
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@nawfal, I initially thought your point about the boxing penalty made sense for struct types, but given that we're testing an object obj; variable, isn't it already boxed when this tends to be tested? Is there a case where you need to test ...
When do I use a dot, arrow, or double colon to refer to members of a class in C++?
...d for three different scenarios that are always well-defined. Knowing this allows you to immediately know quite a lot about a and b just by looking at a::b, a.b, or a->b, respectively, in any code you look at.
a::b is only used if b is a member of the class (or namespace) a. That is, in this c...
Remote debugging a Java application
...ome people are cutting and pasting the invocation here. The answer I originally gave was relevant for the OP only. Here's a more modern invocation style (including using the more conventional port of 8000):
java -agentlib:jdwp=transport=dt_socket,server=y,address=8000,suspend=n <other arguments&...
How to place and center text in an SVG rectangle
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An easy solution to center text horizontally and vertically in SVG:
Set the position of the text to the absolute center of the element in which you want to center it:
If it's the parent, you could just do x="50%" y ="50%".
If it's another element, x would be th...
Passing data between a fragment and its container activity
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In your fragment you can call getActivity().
This will give you access to the activity that created the fragment. From there you can obviously call any sort of accessor methods that are in the activity.
e.g. for a method called getResult() on your A...
What does CultureInfo.InvariantCulture mean?
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Not all cultures use the same format for dates and decimal / currency values.
This will matter for you when you are converting input values (read) that are stored as strings to DateTime, float, double or decimal. It will also ...
When is “Try” supposed to be used in C# method names?
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Basically, if you have a TryParse method, you should have a Parse method that throws when TryParse would return false. Conversely, if you have a Parse method, you should consider having a TryParse method that return false when Par...
What's the role of GetHashCode in the IEqualityComparer in .NET?
...bjects - so the hash code is not necessarily unique.
A dictionary is a really cool data structure that trades a higher memory footprint in return for (more or less) constant costs for Add/Remove/Get operations. It is a poor choice for iterating over though. Internally, a dictionary contains an arr...
How to add a line break in an Android TextView?
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'\r' actually shows as 'r' in text. So, as others suggested, '\n' does the trick.
– Miha Markic
May 10 '17 at 12:30
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Foreign Key to multiple tables
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You have a few options, all varying in "correctness" and ease of use. As always, the right design depends on your needs.
You could simply create two columns in Ticket, OwnedByUserId and OwnedByGroupId, and have nullable Foreign Keys to each table....