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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...
How to get the first column of a pandas DataFrame as a Series?
...c wasn't there yet back then. In 2016, the correct answer is Jeff's (after all he's pandas God, mind you ;-)). I'm not sure what's SO's policy regarding update of answers due to API change; I'm honestly surprised by the number of votes for this answer, didn't think it was that useful to people...
...
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
...
How to reuse an ostringstream?
...
I'm not seeing the failing behavior on VS2012. Furthermore, calling clear will cause the failbit to be set if the stream is empty. While just calling seekp should simply return if no stream exists.
– Jonathan Mee
Jul 8 '14 at...
Why do people put code like “throw 1; ” and “for(;;);” in front of json responses? [du
...ruct, they'll be the attacker's own versions of those objects, with potentially-unexpected behaviour.
For example, you can hack a setter-property into Object, that would betray the values written in object literals:
Object.prototype.__defineSetter__('x', function(x) {
alert('Ha! I steal '+x);
...
Port 80 is being used by SYSTEM (PID 4), what is that?
...P adress is 0.0.0.0, state = LISTENING: means that port 80 is listening to all interfaces (not used)
How to read NETSTAT -AN results:
https://sites.google.com/site/xiangyangsite/home/technical-tips/linux-unix/networks-related-commands-on-linux/how-to-read-netstat--an-results
...
Vertical (rotated) label in Android
...d simple vertical text implementation, extending TextView. This means that all standard styles of TextView may be used, because it is extended TextView.
public class VerticalTextView extends TextView{
final boolean topDown;
public VerticalTextView(Context context, AttributeSet attrs){
...
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...
Can a C# class inherit attributes from its interface?
...h is searched for the attributes.</param>
/// <returns>Returns all attributes.</returns>
public static T[] GetCustomAttributes<T>( this Type type ) where T : Attribute
{
return GetCustomAttributes( type, typeof( T ), false ).Select( arg => (T)arg ).ToArray();
}
/// <...