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How expensive is the lock statement?
I've been experimenting with multi threading and parallel processing and I needed a counter to do some basic counting and statistic analysis of the speed of the processing. To avoid problems with concurrent use of my class I've used a lock statement on a private variable in my class:
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Why do we always prefer using parameters in SQL statements?
...uld be
SELECT empSalary from employee where salary = 0 or 1=1
whereby all empSalaries would be returned.
Further, a user could perform far worse commands against your database, including deleting it If they wrote 0; Drop Table employee:
SELECT empSalary from employee where salary = 0; Drop Ta...
Searching if value exists in a list of objects using Linq
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Because not all collections have Exists, and it does not take a lambda expression, but rather the object we are looking for itself.
– zvolkov
Jul 9 '14 at 12:10
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PHP Remove elements from associative array
...',
4 => 'Completed',
5 => 'Mark As Spam',
);
That would allow you to use your values of key as indexes to access the array...
And you'd be able to use functions to search on the values, such as array_search() :
$indexCompleted = array_search('Completed', $array);
unset($array[$...
How can I disable ARC for a single file in a project?
... objects) where the rules of ARC are a little more fragile right now. I recall hearing that there was a way to disable ARC on a per-file basis, though I have been unable to find this option.
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Why can't an anonymous method be assigned to var?
...type of a lambda or anonymous method is Func of something. We'd still have all kinds of problems. What types would you like to be inferred for the following cases?
var x1 = (ref int y)=>123;
There is no Func<T> type that takes a ref anything.
var x2 = y=>123;
We don't know the type...
How to iterate over a JSONObject?
I use a JSON library called JSONObject (I don't mind switching if I need to).
15 Answers
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Select N random elements from a List in C#
... time you get to the end you will have your 5 items, and often you'll have all of them before that.
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How to get client's IP address using JavaScript?
...that can return JSON (along with jQuery to make things simpler). Below are all the free active IP lookup services I could find and the information they return. If you know of any more, then please add a comment and I'll update this answer.
Cloudflare
Try it: https://www.cloudflare.com/cdn-cgi/trace...
psql - save results of command to a file
I'm using psql's \dt to list all tables in a database and I need to save the results.
10 Answers
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