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Overriding fields or properties in subclasses
I have an abstract base class and I want to declare a field or a property that will have a different value in each class that inherits from this parent class.
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Best way to create an empty object in JSON with PHP?
...result in an empty object, some might therefor say that your code is valid and that it's the method to use.
PHP: Objects - Manual
If a value of any other type is converted to an object, a new instance of the stdClass built-in class is created. If the value was NULL, the new instance will be empty.
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Writing data into CSV file in C#
...a simple solution to a simple question), however due to this becoming more and more popular, I'd recommend using the library CsvHelper that does all the safety checks, etc.
CSV is way more complicated than what the question/answer suggests.
Original Answer
As you already have a loop, consider d...
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.
You could create M:M referen...
The purpose of Model View Projection Matrix
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The model, view and projection matrices are three separate matrices. Model maps from an object's local coordinate space into world space, view from world space to camera space, projection from camera to screen.
If you compose all three, you...
How to send a stacktrace to log4j?
Say you catch an exception and get the following on the standard output (like, say, the console) if you do a e.printStackTrace() :
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Format SQL in SQL Server Management Studio
...h complete T-SQL batch/script support (any DDL, any DML), SSMS Plugin, command-line bulk formatter, and other options.
It's available for immediate/online use at http://poorsql.com, and just today graduated to "version 1.0" (it was in beta version for a few months), having just acquired support for...
How to loop through an array containing objects and access their properties
I want to cycle through the objects contained in an array and change the properties of each one. If I do this:
15 Answers
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Why does 'git commit' not save my changes?
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As the message says:
no changes added to commit (use "git add" and/or "git commit -a")
Git has a "staging area" where files need to be added before being committed, you can read an explanation of it here.
For your specific example, you can use:
git commit -am "save arezzo files"
(...
PowerShell and the -contains operator
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The -Contains operator doesn't do substring comparisons and the match must be on a complete string and is used to search collections.
From the documentation you linked to:
-Contains
Description: Containment operator. Tells whether a collection of reference values includes a...