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How to TryParse for Enum value?
...type.IsDefined(typeof(FlagsAttribute), true)) && (input.IndexOfAny(_enumSeperators) < 0))
return EnumToObject(type, underlyingType, names, values, input, out value);
// multi value enum
string[] tokens = input.Split(_enumSeperators, StringSplitOptions.RemoveEm...
How to prevent ifelse() from turning Date objects into numeric objects
...
You may use data.table::fifelse (data.table >= 1.12.3) or dplyr::if_else.
data.table::fifelse
Unlike ifelse, fifelse preserves the type and class of the inputs.
library(data.table)
dates <- fifelse(dates == '2011-01-01', dates - 1, dates)
str(dates)
# Date[1:5], format: "2010-12-31" "2...
Is there a max array length limit in C++?
... the size thereof). It is given by the maximum value the system's std::size_t can take. This data type is large enough to contain the size in bytes of any object
The other limit is a physical memory limit. The larger your objects in the array are, the sooner this limit is reached because memory is ...
AtomicInteger lazySet vs. set
...erve as a soft barrier costing 20 cycles on nehelem intel cpu)
on x86 (x86_64) such a barrier is much cheaper performance-wise than volatile or AtomicLong getAndAdd ,
In an one producer, one consumer queue scenario, xchg soft barrier can force the line of codes before the lazySet(sequence+1) for ...
MySql Table Insert if not exist otherwise update
... if an existing row is set to its current values. If you specify the CLIENT_FOUND_ROWS flag to mysql_real_connect() when connecting to mysqld, the affected-rows value is 1 (not 0) if an existing row is set to its current values...
...
NULL vs nullptr (Why was it replaced?) [duplicate]
...ough I suppose there are still cases it cannot replace such as std::nullptr_t as an overload. Also, I don't think I'd use (int)NULL since semantically NULL is supposed to be pointer and may be actually be defined as nullptr. You're not guaranteed to get a 0 when to cast nullptr to int. Perhaps (i...
How to safely call an async method in C# without await
...it completes, then you can do this:
public string GetStringData()
{
var _ = MyAsyncMethod();
return "hello world";
}
BTW, this is not a "common problem". It's very rare to want to execute some code and not care whether it completes and not care whether it completes successfully.
Update:
Sin...
Force browser to clear cache
... changes, one way is to to "cache busting" is by appending something like "_versionNo" to the file name for each release. For example:
script_1.0.css // This is the URL for release 1.0
script_1.1.css // This is the URL for release 1.1
script_1.2.css // etc.
Or alternatively do it after the fil...
How to completely uninstall Visual Studio 2010?
...tudio 2010 Uninstall Utility. It comes with three options:
Default (VS2010_Uninstall-RTM.ENU.exe)
Full (VS2010_Uninstall-RTM.ENU.exe /full)
Complete (VS2010_Uninstall-RTM.ENU.exe /full /netfx)
The above link explains the uninstaller in greater detail - I recommend reading the comments on the artic...
How does this giant regex work?
...36\x34\x5F\x64\x65\x63\x6F\x64\x65\x28
is acutally:
eval(gzinflate(base64_decode(
This is the code will print out the source code for this backdoor. However i would not execute the resulting PHP code, unless it is on a disposable virtual machine.
<?php
print gzinflate(base64_decode("7b1tV...