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Get all column names of a DataTable into string array using (LINQ/Predicate)
...details of your code. But essentially: A DataGrid is not the same as a DataTable.
– Daniel Hilgarth
May 17 '13 at 8:08
3
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Entity Framework code first unique column
...ou will see this error with Entity Framework Code First:
Column 'x' in table 'dbo.y' is of a type that is invalid for use as a key column in an index.
The reason is because of this:
SQL Server retains the 900-byte limit for the maximum total size of all index key columns."
(from: http://...
When should you not use virtual destructors?
...mean every allocated object increases in memory cost by a virtual function table pointer.
So if your program involves allocating a very large number of some object, it would be worth avoiding all virtual functions in order to save the additional 32 bits per object.
In all other cases, you will sav...
How to convert View Model into JSON object in ASP.NET MVC?
...erializer is pretty crap.
doing it in the controller at least makes it testable (although not exactly like the above - you probably want to take an ISerializer as a dependency so you can mock it)
Update also, regarding your JavaScript, it would be good practice to wrap ALL the widget JS you have a...
vertical alignment of text element in SVG
...-direction is the position of the "ideographic"
baseline in the baseline-table of the object being aligned.
W3C Source
Unfortunately, although this is the "correct" way of achieving what you're after it would appear Firefox have not implemented a lot of the presentation attributes for the SVG T...
How can I access Google Sheet spreadsheets only with Javascript?
... even though it's Python code, most API requests have JSON & easily portable to JS):
Migrating SQL data to a Sheet (code deep dive post)
Formatting text using the Sheets API (code deep dive post)
Generating slides from spreadsheet data (code deep dive post)
Those and others in the Sheets API v...
Django ManyToMany filter()
...
another way to do this is by going through the intermediate table. I'd express this within the Django ORM like this:
UserZone = User.zones.through
# for a single zone
users_in_zone = User.objects.filter(
id__in=UserZone.objects.filter(zone=zone1).values('user'))
# for multiple zo...
Detect if an input has text in it using CSS — on a page I am visiting and do not control?
...r spec
The Mozilla/Firefox supported selectors
Cross-browser, CSS3 support table
The :empty selector refers only to child nodes, not input values.
[value=""] does work; but only for the initial state. This is because a node's value attribute (that CSS sees), is not the same as the node's value pr...
MySQL - ORDER BY values within IN()
...
SELECT id, name
FROM mytable
WHERE name IN ('B', 'A', 'D', 'E', 'C')
ORDER BY FIELD(name, 'B', 'A', 'D', 'E', 'C')
The FIELD function returns the position of the first string in the remaining list of strings.
However, it is much better performan...
What is the relative performance difference of if/else versus switch statement in Java?
...ere are more than two if/else blocks glued together or its size is unpredictable, then you may highly consider a switch statement.
Alternatively, you can also grab Polymorphism. First create some interface:
public interface Action {
void execute(String input);
}
And get hold of all implemen...