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Passing two command parameters using a WPF binding
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Firstly, if you're doing MVVM you would typically have this information available to your VM via separate properties bound from the view. That saves you having to pass any parameters at all to your commands.
However, you could also multi-bind and use a converter to cre...
How do I write a custom init for a UIView subclass in Swift?
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The init(frame:) version is the default initializer. You must call it only after initializing your instance variables. If this view is being reconstituted from a Nib then your custom initializer will not be called, and instead the init?(coder:) version will be called. Since Swift now req...
How do you make an array of structs in C?
...bout the placement between the declaration of the struct type and then actually making an instance of it - I have a different struct, one that I defined the contents of below where I first make an instance of it (just one this time, not an array), so why didn't this make the massive series of errors...
Git diff between current branch and master but not including unmerged master commits
I want a diff of all changes in a branch that is not merged to master yet.
3 Answers
3...
What to add for the update portion in ConcurrentDictionary AddOrUpdate
...d] = sessionId;
Store a key/value pair into the dictionary unconditionally, overwriting any value for that key if the key already exists: Use the indexer’s setter
(See: http://blogs.msdn.com/b/pfxteam/archive/2010/01/08/9945809.aspx)
The indexer is atomic, too. If you pass a function inst...
What is the difference between setUp() and setUpClass() in Python unittest?
...erence (as noted in the answer by Benjamin Hodgson) is that setUpClass is called only once and that is before all the tests, while setUp is called immediately before each and every test. (NB: The same applies to the equivalent methods in other xUnit test frameworks, not just Python's unittest.)
From...
CSS div element - how to show horizontal scroll bars only?
...nless you make the content large enough to require them.
However you typically do in IE due to a bug. Check in other browsers (Firefox etc.) to find out whether it is in fact only IE that is doing it.
IE6-7 (amongst other browsers) supports the proposed CSS3 extension to set scrollbars independent...
How do you append to a file in Python?
...n C++. If you forget close(), it might take a while before the file is actually closed. It is easier that you might think to forget it when the code has multiple exit points, exceptions and so on.
– Petter
Jun 13 '13 at 17:37
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Integer.toString(int i) vs String.valueOf(int i)
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String.valueOf(int) just calls Integer.toString(i) directly. So best to call Integer.toString(int).
– djchapm
May 21 '19 at 16:21
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T-SQL - function with default parameters
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you have to call it like this
SELECT dbo.CheckIfSFExists(23, default)
From Technet:
When a parameter of the function has a default value, the keyword
DEFAULT must be specified when the function is called in order to
retrieve th...