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What to add for the update portion in ConcurrentDictionary AddOrUpdate
...sionID.ToString();
userDic.AddOrUpdate(
authUser.UserId,
sessionId,
(key, oldValue) => sessionId);
I.e. the Func always returns the sessionId, so that both Add and Update set the same value.
BTW: there is a sample on the MSDN page.
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Convert audio files to mp3 using ffmpeg
...u could use this command:
ffmpeg -i input.wav -vn -ar 44100 -ac 2 -b:a 192k output.mp3
Explanation of the used arguments in this example:
-i - input file
-vn - Disable video, to make sure no video (including album cover image) is included if the source would be a video file
-ar - Set the audio ...
Error Dropping Database (Can't rmdir '.test\', errno: 17)
...nted the database. It will not, however, remove non-table files, whereby making it not possible to remove the directory.
MySQL displays an error message when it cannot remove the directory
you can really drop the database manually by removing any remaining files in the database directory and then...
Is there a Mutex in Java?
Is there a Mutex object in java or a way to create one?
I am asking because a Semaphore object initialized with 1 permit does not help me.
Think of this case:
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Java / Android - How to print out a full stack trace?
In Android (Java) how do I print out a full stack trace? If my application crashes from nullPointerException or something, it prints out a (almost) full stack trace like so:
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is it possible to select EXISTS directly as a bit?
I was wondering if it's possible to do something like this (which doesn't work):
9 Answers
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What is PostgreSQL explain telling me exactly?
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Milen A. RadevMilen A. Radev
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How do I write unencoded Json to my View using Razor?
...'m trying to write an object as JSON to my Asp.Net MVC View using Razor, like so:
3 Answers
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In vim, how do I go back to where I was before a search?
Programming in vim I often go search for something, yank it, then go back to where I was, insert it, modify it.
7 Answers
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Is there an expression for an infinite generator?
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ncoghlanncoghlan
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