65 řádky
1,7 KiB
Ruby
65 řádky
1,7 KiB
Ruby
#---
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# Excerpted from "Agile Web Development with Rails",
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# published by The Pragmatic Bookshelf.
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# Copyrights apply to this code. It may not be used to create training material,
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# courses, books, articles, and the like. Contact us if you are in doubt.
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# We make no guarantees that this code is fit for any purpose.
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# Visit http://www.pragmaticprogrammer.com/titles/rails4 for more book information.
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#---
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$: << File.dirname(__FILE__)
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require "connect"
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require "logger"
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require "pp"
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#ActiveRecord::Base.logger = Logger.new(STDERR)
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require "rubygems"
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require "active_record"
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class LineItem < ActiveRecord::Base
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end
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LineItem.delete_all
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LineItem.create(:quantity => 1, :product_id => 27, :order_id => 13, :unit_price => 29.95)
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LineItem.create(:quantity => 2, :unit_price => 29.95)
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LineItem.create(:quantity => 1, :unit_price => 44.95)
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result = LineItem.find(:first)
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p result.quantity
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p result.unit_price
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result = LineItem.find_by_sql("select quantity, quantity*unit_price " +
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"from line_items")
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pp result[0].attributes
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result = LineItem.find_by_sql("select quantity,
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quantity*unit_price as total_price " +
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"from line_items")
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pp result[0].attributes
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p result[0].total_price
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sales_tax = 0.07
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p result[0].total_price * sales_tax
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class LineItem < ActiveRecord::Base
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def total_price
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Float(read_attribute("total_price"))
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end
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CUBITS_TO_INCHES = 2.54
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def quantity
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read_attribute("quantity") * CUBITS_TO_INCHES
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end
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def quantity=(inches)
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write_attribute("quantity", Float(inches) / CUBITS_TO_INCHES)
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end
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end
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p result[0].quantity
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result[0].quantity = 500
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p result[0].save
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