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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
...
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...
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...
What are the differences between a multidimensional array and an array of arrays in C#?
...t32 'value') cil managed
{
// Code size 7 (0x7)
.maxstack 8
IL_0000: ldarg.0
IL_0001: ldarg.1
IL_0002: ldelem.ref
IL_0003: ldarg.2
IL_0004: ldarg.3
IL_0005: stelem.i4
IL_0006: ret
} // end of method Program::SetElementAt
.method private hidebysig static void SetElem...
Making macOS Installer Packages which are Developer ID ready
Note: This is for OS X Installer packages only, packages for submission to the Mac App Store follow different rules.
5 ...
Multi-line regex support in Vim
...t of other differences between Vim and Perl regexes.
Instead you can use \_., which means "match any single character including newline". It's a bit shorter than what you have. See :h /\_..
/This\_.*text/
share
...
String.Empty versus “” [duplicate]
...implies, there difference
between String.Empty and “” are pretty
small, but there is a difference. “”
actually creates an object, it will
likely be pulled out of the string
intern pool, but still… while
String.Empty creates no object… so if
you are really looking for ultim...
How do you add an in-app purchase to an iOS application?
How do you add an in-app purchase to an iOS app? What are all the details and is there any sample code?
5 Answers
...
Does a view exist in ASP.NET MVC?
... aside: one of our engineers (since moved on) built a custom view engine (called MultiTenantViewEngine, so you get a sense of its purpose) that implements FindView to throw a HttpException (404) if it can't find the given view. Is this good practice? I have no idea. But wouldn't be surprised if t...
Change private static final field using Java reflection
...get around private and resetting the modifier to get rid of final, and actually modify a private static final field.
Here's an example:
import java.lang.reflect.*;
public class EverythingIsTrue {
static void setFinalStatic(Field field, Object newValue) throws Exception {
field.setAccessibl...