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Send and receive messages through NSNotificationCenter in Objective-C?
...
@implementation TestClass
- (void) dealloc
{
// If you don't remove yourself as an observer, the Notification Center
// will continue to try and send notification objects to the deallocated
// object.
[[NSNotificationCenter defaultCenter] removeO...
How do you change the datatype of a column in SQL Server?
...to drop everything and recreate it, which is tedious and grunt work, especially if you have many foreign references on that column. e.g. when changing from tinyint to int.
– Hrvoje Batrnek
Jun 9 '18 at 14:18
...
How to delete migration files in Rails 3
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I usually:
Perform a rake db:migrate VERSION=XXX on all environments, to the version before the one I want to delete.
Delete the migration file manually.
If there are pending migrations (i.e., the migration I removed was not the...
Launch Bootstrap Modal on page load
I don't know javascript at all. The bootstrap documentation says to
18 Answers
18
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PHP session lost after redirect
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First, carry out these usual checks:
Make sure session_start(); is called before any sessions are being called. So a safe bet would be to put it at the beginning of your page, immediately after the opening <?php declaration before anything else. Also ensure there are no whitespaces/tabs be...
How to use a variable inside a regular expression?
...wise we must write "\\\\boundary" in the regex (four backslashes). Additionally, without '\r', \b' would not converted to a word boundary anymore but to a backspace!
re.escape:
Basically puts a backspace in front of any special character. Hence, if you expect a special character in TEXTO, you need...
How to create a GUID/UUID using iOS
...tring = CFUUIDCreateString(NULL, theUUID);
CFRelease(theUUID);
return (__bridge NSString *)string;
}
EDIT: Jan, 29 2014:
If you're targeting iOS 6 or later, you can now use the much simpler method:
NSString *UUID = [[NSUUID UUID] UUIDString];
...
Property getters and setters
...g to backup the computed property. Try this:
class Point {
private var _x: Int = 0 // _x -> backingX
var x: Int {
set { _x = 2 * newValue }
get { return _x / 2 }
}
}
Specifically, in the Swift REPL:
15> var pt = Point()
pt: Point = {
_x = 0
}
16> pt.x = 10...
What are CN, OU, DC in an LDAP search?
...N = Common Name
OU = Organizational Unit
DC = Domain Component
These are all parts of the X.500 Directory Specification, which defines nodes in a LDAP directory.
You can also read up on LDAP data Interchange Format (LDIF), which is an alternate format.
You read it from right to left, the right-m...
Way to ng-repeat defined number of times instead of repeating over array?
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Update (9/25/2018)
Newer versions of AngularJS (>= 1.3.0) allow you to do this with only a variable (no function needed):
<li ng-repeat="x in [].constructor(number) track by $index">
<span>{{ $index+1 }}</span>
</li>
$scope.number = 5;
This was not poss...