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What to add for the update portion in ConcurrentDictionary AddOrUpdate
...f an update. I guess in your case (since you don't distinguish between add and update) this would be:
var sessionId = a.Session.SessionID.ToString();
userDic.AddOrUpdate(
authUser.UserId,
sessionId,
(key, oldValue) => sessionId);
I.e. the Func always returns the sessionId, so that both A...
Psql list all tables
...in all schemas. This will include tables in pg_catalog, the system tables, and those in information_schema. There's no built-in way to say "all tables in all user-defined schemas"; you can, however, set your search_path to a list of all schemas of interest before running \dt.
You may want to do thi...
How do I create a datetime in Python from milliseconds?
...
What about this? I presume it can be counted on to handle dates before 1970 and after 2038.
target_date_time_ms = 200000 # or whatever
base_datetime = datetime.datetime( 1970, 1, 1 )
delta = datetime.timedelta( 0, 0, 0, target_date_time_ms )
target_date = base_datetim...
How to write a multidimensional array to a text file?
... read back in with numpy.loadtxt. Therefore, we can be a bit more verbose, and differentiate the slices using commented out lines. By default, numpy.loadtxt will ignore any lines that start with # (or whichever character is specified by the comments kwarg). (This looks more verbose than it actually...
How to read data from a zip file without having to unzip the entire file
...Zip does in the constructor is seek to the "directory" inside the zipfile, and then read it and populate the list of entries. At that point, if your app calls Extract() on one entry, DotNetZip seeks to the proper place in the zip file, and decompresses the data for just that entry.
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Converting NSString to NSDate (and back again)
... NSString like " 01/02/10 " (meaning 1st February 2010) into an NSDate ? And how could I turn the NSDate back into a string?
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Programming with white text on black background?
...e? Is it any better than the traditional black on white? What are the pros and cons?
14 Answers
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What can I do with a moved-from object?
Does the standard define precisely what I can do with an object once it has been moved from? I used to think that all you can do with a moved-from object is do destruct it, but that would not be sufficient.
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Datatype for storing ip address in SQL Server
...s (no, not even an INT32/INT(4), the numeric textual form that we all know and love (255.255.255.255) being just the display conversion of its binary content).
If you do it this way, you will want functions to convert to and from the textual-display format:
Here's how to convert the textual displa...
Styling text input caret
...e caret of a focused <input type='text'/> . Specifically, the color and thickness.
5 Answers
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