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Do you need to dispose of objects and set them to null?
... of scope (such as a static field whose value you no longer need), but overall there is usually no need to set to null.
Regarding disposing objects, I agree with @Andre. If the object is IDisposable it is a good idea to dispose it when you no longer need it, especially if the object uses unmanaged...
What is the difference between “Class.forName()” and “Class.forName().newInstance()”?
...demo = (Demo) clazz.newInstance();
}
}
As explained in its javadoc, calling Class.forName(String) returns the Class object associated with the class or interface with the given string name i.e. it returns test.Demo.class which is affected to the clazz variable of type Class.
Then, calling cla...
PHP + MySQL transactions examples
I really haven't found normal example of PHP file where MySQL transactions are being used. Can you show me simple example of that?
...
Rails extending ActiveRecord::Base
...the ActiveSupport::Concern documentation for more details.
Create a file called active_record_extension.rb in the lib directory.
require 'active_support/concern'
module ActiveRecordExtension
extend ActiveSupport::Concern
# add your instance methods here
def foo
"foo"
end
# add y...
Unable to simultaneously satisfy constraints, will attempt to recover by breaking constraint
...the memory pointers are the same. So we know what is going on now. Additionally you can find NSLayoutConstraint in view hierarchy. Since it is selected in View, it selected in Navigator also.
If you need you may also print it on console using address pointer:
(lldb) po 0x17dce920
<UIView: 0x1...
How do I parse a string with a decimal point to a double?
...
Well, XmlConvert is not really intended to be used to parse a single double value in code. I prefer to use double.Parse or Convert.ToDouble that make my intention obvious.
– Mehrdad Afshari
Aug 30 '09 at 21:29
...
Calc of max, or max of calc in CSS
...
min(), max(), and clamp() are finally available!
Starting in Firefox 75, Chrome 79, and Safari 11.1 (except clamp).
min() and max() take any number of arguments.
clamp() has syntax clamp(MIN, VAL, MAX) and is equivalent to max(MIN, min(VAL, MAX)).
min() ...
How can I backup a remote SQL Server database to a local drive?
... script" to "Schema and data" value
In the next four windows, hit 'select all' and then next,
Choose to script to a new query window
Once it's done its thing, you'll have a backup script ready in front of you. Create a new local (or remote) database, and change the first 'USE' statement in the s...
Mockito: Trying to spy on method is calling the original method
... = new LinkedList();
List spy = spy(list);
// Impossible: real method is called so spy.get(0) throws IndexOutOfBoundsException (the list is yet empty)
when(spy.get(0)).thenReturn("foo");
// You have to use doReturn() for stubbing
doReturn("foo").when(spy).get(0);
In your case it goes something l...
JavaScript by reference vs. by value [duplicate]
...
My understanding is that this is actually very simple:
Javascript is always pass by value, but when a variable refers to an object (including arrays), the "value" is a reference to the object.
Changing the value of a variable never changes the underlying prim...