大约有 23,000 项符合查询结果（耗时：0.0468秒） [XML]
Rails 4 multiple image or file upload using carrierwave
...avatar:string
rake db:migrate
In post.rb
class Post < ActiveRecord::Base
has_many :post_attachments
accepts_nested_attributes_for :post_attachments
end
In post_attachment.rb
class PostAttachment < ActiveRecord::Base
mount_uploader :avatar, AvatarUploader
belongs_to :post
end...
How can I find all of the distinct file extensions in a folder hierarchy?
...folder):
for f in *.*; do printf "%s\n" "${f##*.}"; done | sort -u
I've based this upon this forum post, credit should go there.
share
|
improve this answer
|
follow
...
Is unsigned integer subtraction defined behavior?
...n the two expressions we are discussing is performed in type unsigned int, based on the operand types. The result of the addition is unsigned int. Then that result is implicitly converted to the type required in context, a conversion which fails because the value is not representable in the new ty...
Difference between Observer, Pub/Sub, and Data Binding
...the functions stored in that array.
If we want to group observers handlers based on different events. We just need to modify that observersList to an Object like
var events = {
"event1": [handler1, handler2],
"event2": [handler3]
}
see this pubsub example for details.
and people call this v...
Can you create nested WITH clauses for Common Table Expressions?
...s a recursive query:
WITH y
AS
(
SELECT x, y, z
FROM MyTable
WHERE [base_condition]
UNION ALL
SELECT x, y, z
FROM MyTable M
INNER JOIN y ON M.[some_other_condition] = y.[some_other_condition]
)
SELECT *
FROM y
You may not need this functionality. I've done the following just to o...
Removing duplicate objects with Underscore for Javascript
...
If you're looking to remove duplicates based on an id you could do something like this:
var res = [
{id: 1, content: 'heeey'},
{id: 2, content: 'woah'},
{id: 1, content:'foo'},
{id: 1, content: 'heeey'},
];
var uniques = _.map(_.groupBy(res,function(doc)...
Using build types in Gradle to run same app that uses ContentProvider on one device
...uthority renaming
I guess all of you have heard of the new Android Gradle-based build system. Let's be honest, this new build system is a huge step forward compared to the previous one. It is not final yet (as of this writing, the latest version is 0.4.2) but you can already use it safely in most o...
Is there a job scheduler library for node.js? [closed]
...
agenda is based on node-cron with a persisten layer (mongo). so the answer above is better.
– drdrej
Feb 6 '14 at 14:57
...
How to debug a maven goal with intellij idea?
...a negative score, it did help me fix the issue I had (how to debug a maven-based project in IntelliJ), and when "Googling" the issue it led me to this page.
– gbmhunter
Oct 17 '16 at 21:31
...
what is the difference between a portlet and a servlet?
... Source: Servlets Vs Portlets
Similarities
Servlets and Portlets are web based components which use Java for
their implementation.
Portlets are managed by a portlet container just like servlet is
managed by servlet container.
Both static and dynamic content can be generated by Portlets and
Servl...