1.try 永远不会抛出异常 在 没有的时候 返回 nil
2.find(:first, :condotions) 方法 不言而与
3.find(:all, :select, :conditions)
4.发送post请求 可以在shell中执行
5.Ruby 中纯数据结构 ( Struct 与 OpenStruct )
讲一下它俩之间的区别:
Struct 需要开头明确声明字段; 而 OpenStruct 人如其名, 随时可以添加属性
Struct 性能优秀; 而 OpenStruct 差点, 具体的性能差距可看这里:http://stackoverflow.com/questions/1177594/ruby-struct-vs-openstruct
Struct 是 Ruby 解释器内置, 用 C 实现; OpenStruct 是 Ruby 标准库, Ruby 实现
API 不同: Struct API 与 OpenStruct
6. MIme::Type.register
7.config/initializers/secure_problem_solved.rb
8.config/initializers/new_rails_default.rb
# Store the full class name (including module namespace) in STI type column.
ActiveRecord::Base.store_full_sti_class = true
end
ActionController::Routing.generate_best_match = false
# Use ISO 8601 format for JSON serialized times and dates.
ActiveSupport.use_standard_json_time_format = true
# Don't escape HTML entities in JSON, leave that for the #json_escape helper.
# if you're including raw json in an HTML page.
ActiveSupport.escape_html_entities_in_json = false
9.MemCacheStore 缓存
localhost::callback_lock
@_cache.write(pay_channel.channel_id,'true')
v = @_cache.read(pay_channel.channel_id)
if v.nil? || v != 'true'
return false
else
return true
end
end
10.联合索引
https://github.com/momoplan
0.Hash assert_valid_keys 白名单
11.puma -C puma_service_qa.rb
12.pow
13. Time
14.merchant.instance_of? MplusMerchant
15.will_paginate rails
安装之后需要修改config/environment.rb文件
在文件的最后添加:
最好有个include
16. # Excel Generator
MONTH = 1.upto(12).to_a
def self.total_to_xls(year = '2012', opts = {})
book = Spreadsheet::Workbook.new
sheet1 = book.create_worksheet
months = MONTH
months = opts[:month].to_s.split(/,/) if opts[:month]
fixed_row = months.collect{ |m| m.to_s + '月' }.insert(0, '')
sheet1.row(0).concat(fixed_row)
row1 = ['']
(months.size - 1).times { row1 << ['用户数', '金额', '订单数'] }
sheet1.row(1).concat(row1.flatten!)
row = 2
sheet1.row(row).insert(0, '全国')
months.each_with_index do |m, i|
sheet1.row(row).insert(i*3 + 1, self.monthly_users_count(m))
sheet1.row(row).insert(i*3 + 2, self.monthly_amount(m))
sheet1.row(row).insert(i*3 + 3, self.monthly_orders_count(m))
end
PROVINCE.each do |province|
row += 1
sheet1.row(row).insert(0, province)
months.each_with_index do |m, i|
sheet1.row(row).insert(i*3 + 1, self.monthly_users_count_by_province(m, province))
sheet1.row(row).insert(i*3 + 2, self.monthly_amount_by_province(m, province))
sheet1.row(row).insert(i*3 + 3, self.monthly_orders_count_by_province(m, province))
end
end
path = "tmp/phone_recharge.xls"
book.write path
path
end
17. inject({})
18.time_str.instance_of?
19.Person.instance_eval
20.class_eval
21.Ruby中 respond_to? 和 send 的用法
http://galeki.is-programmer.com/posts/183.html
因为obj对象没法响应talk这个消息,如果使用 respond_to? 这个方法,就可以实现判断对象能否响应给定的消息了
22.method_missing,一个 Ruby 程序员的梦中情人
23.chomp
chomp方法是移除字符串尾部的分离符,例如/n,/r等...而gets默认的分离符是/n
24. hash.each_pair{|k,v|} & send()
25.config.middleware 通过 rake -T 可以查看, 在config/ - 去除不必的 middleware
26.1.day.ago.strftime('%Y%m%d')
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