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Create a menu Bar in WPF?
...nel>
<Menu DockPanel.Dock="Top">
<MenuItem Header="_File">
<MenuItem Header="_Open"/>
<MenuItem Header="_Close"/>
<MenuItem Header="_Save"/>
</MenuItem>
</Menu>
<StackPanel></StackPa...
Run a callback only if an attribute has changed in Rails
...
Rails 5.1+
class Page < ActiveRecord::Base
before_save :do_something, if: :will_save_change_to_status_id?
private
def do_something
# ...
end
end
The commit that changed ActiveRecord::Dirty is here: https://github.com/rails/rails/commit/16ae3db5a5c6a08383b974ae...
Can Objective-C switch on NSString?
... @abbood For more information about enum, see the posting NS_ENUM & NS_OPTIONS by Mattt Thompson.
– Basil Bourque
Oct 21 '13 at 21:32
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How do you add a Dictionary of items into another Dictionary
...
@animal_chin Because we have to implement half of the language ourselves? Yes. Impressed. Don't get me wrong I love operator overloading. I just don't love having to use it for basic features that should be built in.
...
How to determine whether a given Linux is 32 bit or 64 bit?
...
Try uname -m. Which is short of uname --machine and it outputs:
x86_64 ==> 64-bit kernel
i686 ==> 32-bit kernel
Otherwise, not for the Linux kernel, but for the CPU, you type:
cat /proc/cpuinfo
or:
grep flags /proc/cpuinfo
Under "flags" parameter, you will see various value...
Generate JSON string from NSDictionary in iOS
...ke easier to read).
@interface NSDictionary (BVJSONString)
-(NSString*) bv_jsonStringWithPrettyPrint:(BOOL) prettyPrint;
@end
.
@implementation NSDictionary (BVJSONString)
-(NSString*) bv_jsonStringWithPrettyPrint:(BOOL) prettyPrint {
NSError *error;
NSData *jsonData = [NSJSONSerial...
How to convert CharSequence to String?
...
Returns a string containing the characters in this sequence in the same order as this sequence. The length of the string will be the length of this sequence.
share
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improve this answer
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Checking if a double (or float) is NaN in C++
...d portable solution. You can even test for -ffast-math by testing for the __FAST_MATH__ macro and switch to a different implementation in that case (e.g. use unions and bit twiddling).
– Adam Rosenfield
Mar 27 '11 at 23:45
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How to get the number of days of difference between two dates on mysql?
...iff(DAY, '2016-04-13 11:00:01', '2016-04-14 11:00:00');
(note the opposite order of arguments compared to datediff).
Some examples:
select timestampdiff(DAY, '2016-04-13 11:00:01', '2016-04-14 11:00:00');
returns 0
select timestampdiff(DAY, '2016-04-13 11:00:00', '2016-04-14 11:00:00');
returns 1
s...
Web Service vs WCF Service
...nce of DataContractSerializer and XmlSerializer is that DCS requires field ordering - which is why I don't use DCS for non-transient serialization or contracts! Thus it's possible to break a service used by clients not using the fixed ordering when moving to DCS (or moving to DCS but in a different ...