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Why Would I Ever Need to Use C# Nested Classes [duplicate]
...third parties to create their own subclasses. I have complete control over all the code that runs in any bankaccount object. And all my subclasses can share implementation details via the base class.
share
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Should I call Close() or Dispose() for stream objects?
... StreamWriter etc implements IDisposable interface. That means, we can call Dispose() method on objects of these classes. They've also defined a public method called Close() . Now that confuses me, as to what should I call once I'm done with objects? What if I call both?
...
Oracle: If Table Exists
...her reason (that might be important) the exception is still raised to the caller:
BEGIN
EXECUTE IMMEDIATE 'DROP TABLE ' || table_name;
EXCEPTION
WHEN OTHERS THEN
IF SQLCODE != -942 THEN
RAISE;
END IF;
END;
ADDENDUM
For reference, here are the equivalent blocks for other...
View the Task's activity stack
...
is there a nice way to show all of the tasks&activities stack of the current app via logcat? do we really need to parse the adb command ?
– android developer
Feb 13 '12 at 6:36
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What is Express.js?
...deling) to provide a backend for your Node.js application. Express.js basically helps you manage everything, from routes, to handling requests and views.
Redis is a key/value store -- commonly used for sessions and caching in Node.js applications. You can do a lot more with it, but that's what I'm ...
SVN - Checksum mismatch while updating
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This is not a specific fix at all. You can always delete all your local data and start with a fresh copy from the repo.
– tim
Sep 12 '16 at 9:43
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Is it possible to decrypt MD5 hashes?
...gorithms), it is a one way hash function. Much of the original data is actually "lost" as part of the transformation.
Think about this: An MD5 is always 128 bits long. That means that there are 2128 possible MD5 hashes. That is a reasonably large number, and yet it is most definitely finite. And y...
Extracting text from HTML file using Python
...'d like to extract the text from an HTML file using Python. I want essentially the same output I would get if I copied the text from a browser and pasted it into notepad.
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Why can't Python find shared objects that are in directories in sys.path?
...le LD_LIBRARY_PATH works on many
Unix-like systems, it doesn't work on
all; for example, this functionality
is available on HP-UX but as the
environment variable SHLIB_PATH, and
on AIX this functionality is through
the variable LIBPATH (with the same
syntax, a colon-separated list).
...
Rails: How do I create a default value for attributes in Rails activerecord's model? [duplicate]
...
add_column :status, :string, :default => "P"
....
OR
You can use a callback, before_save
class Task < ActiveRecord::Base
before_save :default_values
def default_values
self.status ||= 'P' # note self.status = 'P' if self.status.nil? might be safer (per @frontendbeauty)
end
end
...