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onKeyPress Vs. onKeyUp and onKeyDown
... an empty input element:
The value of the input element will be an empty string (old value) inside the keypress handler
The value of the input element will be 1 (new value) inside the keyup handler.
This is of critical importance if you are doing something that relies on knowing the new value af...
Intel HAXM installation error - This computer does not support Intel Virtualization Technology (VT-x
...the file is stored under C:\Program Files (x86)\Android\android-studio\sdk\extras\intel\Hardware_Accelerated_Execution_Manager, then I need to copy it to somewhere else.
– User
Sep 4 '14 at 8:14
...
SQL order string as number
...o number
select col from yourtable
order by col + 0
BTW MySQL converts strings from left to right. Examples:
string value | integer value after conversion
--------------+--------------------------------
'1' | 1
'ABC' | 0 /* the string does not contain a number, so the re...
BestPractice - Transform first character of a string into lower case
I'd like to have a method that transforms the first character of a string into lower case.
11 Answers
...
Best way to add “current” class to nav in Rails 3
...nst the current page uri and returns either your current class or an empty string.
I've not tested this thoroughly and I'm very new to RoR (moving over after a decade with PHP) so if this has a major flaw I'd love to hear it.
At least this way you only need 1 helper function and a simple call in e...
Batch file to delete files older than N days
...amples with hundreds of lines of code, and others that required installing extra command line utilities to accomplish the task.
...
Representing graphs (data structure) in Python
...should be expressed only in terms of existence, or whether they carry some extra information.
From Python built-in data types point-of-view, any value contained elsewhere is expressed as a (hidden) reference to the target object. If it is a variable (i.e. named reference), then the name and the ref...
ActiveRecord: size vs count
...many association, size will use the cached count directly, and not make an extra query at all.
class Image < ActiveRecord::Base
belongs_to :product, counter_cache: true
end
class Product < ActiveRecord::Base
has_many :images
end
> product = Product.first # query, load product into m...
List of all special characters that need to be escaped in a regex
... It's safer to escape it. For example, the patterns [-] and [-)] match the string - but not with [(-)].
– Kenston Choi
Sep 12 '16 at 5:28
...
How to pass parameters correctly?
...ssing an rvalue (in this case, one move will be performed).
Account(std::string number, float amount, CreditCard const& creditCard)
: number(number), amount(amount), creditCard(creditCard) // copy here
{ }
Account(std::string number, float amount, CreditCard&& creditCard)
: number(n...