Ruby

Class method The essence of a class method is a single piece method that lives in a single piece of the class. There are three ways to define them, respectively: # method One def Myclass.a_class_method end # Two class MyClass def

Algorithm principle: Compare the adjacent elements. If the first one is bigger than the second one, swap them both.Do the same work for each pair of adjacent elements, from the first pair to the end of the last couple. At this point, the final

Proc Objects Proc are objects that are converted by blocks. There are four ways to create a proc, respectively: Sample code # Law one inc = Proc.new {| x | x + 1} Inc.call (2) #=> 3 # method two inc = Lambda {| x | x + 1} Inc.call (2) # =>

In a file there are many of the following: This topic selected D. .... .... .... And I want to achieve the function is to replace it: This topic selected D. ..... ..... ..... This thing looks a little bit simple, but

Scope Ruby does not have the characteristics of a nested scope (that is, an internal scope that can see an external scope), its scope is completely separate, and once you enter a new scope, the original binding is replaced with a new set of

A constant begins with a capital letter. It should be assigned up to one time. In the current version of Ruby, the re-assignment of constants produces only warnings rather than errors (the Non-ansi version of EVAL.RB does not report this

Global variables begin with $. They can be accessed anywhere in the program. The global variable has a special value nil before initialization. Ruby> $foo Nil ruby> $foo = 5 5 Ruby> $foo 5 Global variables should be used with caution. They are

In general, the definition of the observer pattern should be this: building a clean interface between the source of news that some object has changed and the Consumers O F that news. The Observer pattern establishes a clean interface between the

Regular match Speaking of Ruby, of course, the regular expression mechanism of the regular expression as a strong matching language has been more and more used in different fields, from string verification, matching, to Web page extraction and so

Accept user Input First_Name = Gets.chomp Capitalize first letter first_name.capitalize! Uppercase letters first_name.upcase! The letter becomes lowercase first_name.downcase! Multi-line output

Language-related settings and strings should not be used in views, models, and controllers. These words should be moved to a language file under the Config/locales. When the label of the ActiveRecord model needs to be translated, use the

Keep the schema.rb under version control.Use Rake db:scheme:load instead of rake db:migrate to initialize the empty database.Use rake db:test:prepare to update the schema of the test database. Avoid setting default data in the table. Use the model

When you need to add one or more actions to a RESTful resource (do you really need it?) ), using the member and collection routing. # get ' subscriptions/:id/unsubscribe ' resources:subscriptions # good resources:subscriptions do

Some difficulties in learning ruby language learning comprehension The Ruby language is a relatively simple language because all of its design principles are object-oriented, so it's especially handy to use. Of course, the main reason is

Directly on the code#!/usr/bin/env ruby#encoding:utf-8filename = Argv[0]file = File.Open (filename) =begin column-wise print =endfile.each_line do |line|  Myline = line.chomp! ary = Myline.readlines puts Ary[1]endfile.closeIterate through the rows

Recently doing a scan code login function, for this I also searched the internet about the implementation of the scan login. When this function was completed, I decided to organize the whole realization, so that I can see it later and also

Ruby's garbage collectorIn Ruby, almost everything you do requires memory.The job of the Ruby garbage collector is to manage memory and eventually release objects that are no longer in use. But this would sacrifice a bit of performance, and it would

#将ARGV [0] convert to regular expression typePattern= regexp.new (argv[0])#Devise Gem PackDevise is one of the most widely used authentication gem packages in Ruby. Devise provides us with complete features from registration to login, from forgotten

#encoding: Utf-8Require ' mail 'def Send_email sum,fail,case_path,name,receive SMTP = {: Address = ' smtp.mobanker.com ',:p ort =,:d omain = ' mobanker.com ', : user_name = ' [email protected] ',:p assword = ' nl102thxfd2z! ', :

Ruby saves the data queried by mysql to excel and rubymysql Require "win32ole" require 'pathname' require 'mysql2' excel = WIN32OLE. new ('excel. application ') excel. visible = true # in case you want to see what happensclient = Mysql2: Client. new