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Difference between Select and ConvertAll in C#
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Select is a LINQ extension method and works on all IEnumerable<T> objects whereas ConvertAll is implemented only by List<T>. The ConvertAll method exists since .NET 2.0 whereas LINQ was introduced with 3.5.
You s...
Can someone explain collection_select to me in clear, simple terms?
I am going through the Rails API docs for collection_select and they are god-awful.
2 Answers
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Fastest way to check if a file exist using standard C++/C++11/C?
...r. This does not use many fancy features of C++:
bool is_file_exist(const char *fileName)
{
std::ifstream infile(fileName);
return infile.good();
}
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How to escape apostrophe (') in MySql?
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Here's an example:
SELECT * FROM pubs WHERE name LIKE "%John's%"
Just use double quotes to enclose the single quote.
If you insist in using single quotes (and the need to escape the character):
SELECT * FROM pubs WHERE name LIKE '%John\'s%'...
Why does AngularJS include an empty option in select?
...efined in the specification at http://docs.angularjs.org/api/ng.directive:select , I still get an empty option as the first child of select element.
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Getting value of select (dropdown) before change
The thing I want to achieve is whenever the <select> dropdown is changed I want the value of the dropdown before change. I am using 1.3.2 version of jQuery and using on change event but the value I am getting over there is after change.
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How to auto-indent code in the Atom editor?
...auto-indent your code in the Atom editor? In other editors you can usually select some code and auto-indent it.
11 Answers...
How to disable/enable select field using jQuery?
...gt;
<label for="pizza">I would like to order a</label>
<select id="pizza_kind" name="pizza_kind">
<option>(choose one)</option>
<option value="margaritha">Margaritha</option>
<option value="hawai">Hawai</option>
</select>
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quick random row selection in Postgres
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You might want to experiment with OFFSET, as in
SELECT myid FROM mytable OFFSET floor(random()*N) LIMIT 1;
The N is the number of rows in mytable. You may need to first do a SELECT COUNT(*) to figure out the value of N.
Update (by Antony Hatchkins)
You must use floor he...
Can an int be null in Java?
... primitive types,we have fixed memory size i.e for int we have 4 bytes and char we have 2 bytes. And null is used only for objects because there memory size is not fixed.
So by default we have,
int a=0;
and not
int a=null;
Same with other primitive types and hence null is only used for...