Rails 笔试题

1.What is the notation used for denoting class variables in Ruby?

2.How is class methods defined in Ruby?

3. Whats the difference between symbol and string? 

4.What  it's print in screen?

def multiplier(n) 
  lambda {|data| data.collect{|x| x*n } }
end
doubler = multiplier(2)     # Get a lambda that knows how to double
puts doubler.call([1,2,3])  

5.What is the use of load and require in Ruby?
6.How do Dynamic define a Methods  and call a methods dynamically
7.Use  method_missing()  implement dynamic attribute

  class AccessorUtil
  def initialize
      #1 you could write your code here
  end

  def method_missing(name,*args)
      #2 you could write your code here
  end
end 
class StepUtil<AccessorUtil  end
test = StepUtil.new
test.send "a1=",9333
aaa= test.send "a1"
puts aaa

8.How do hook method work, please give example of hook method

9.What is the result after execution.

   "ruby123"[/\d+/] 
    "ruby123"[/([a-z]+)(\d+)/,1]  
"ruby123"[/([a-z]+)(\d+)/,2]

10. Point out the wrong code of Watir

require 'watir'

class WebPageUtil
  def initialize(ie)
    @dAttr=Hash.new
    @ie=ie
    @arr = ["text_field","checkbox","select_list","area","radio"]
    @filter = ["exampleid"]
  end

  def fill_form
    @dAttr.each do |name,value|
      if(!@filter.include?(name))
        @arr.each do |watir_method|
          begin
            el=@ie.send watir_method,:name,name
            if el.exist?
              case watir_method
              when "text_field"
                el.set value.to_s
              when "checkbox"
                if value.to_s =""
                  el.clear
                else
                  el.set
                end
              when "select_list"
                el.getAllContents
                el.set value.to_s
              when "area"
                el.append value.to_s
              when "radio"
                if value.to_s ==""
                  el.clear
                else
                  el.set
                end
              end
            end
          rescue
          end
        end
      end
    end

  end

  def method_missing(name,*args)
    key = name.to_s
    if name.to_s.include?("=")
      key = name.to_s.chop
      @dAttr[key]=args
    else
      if @dAttr.has_key?(name.to_s)
        return @dAttr[key].to_s
      else
        return nil
      end
    end
  end
end

ie = Watir::Browser.new
ie.goto "http://www.google.com"
dm= WebPageUtil.new(ie)
dm.q="goole"
dm.fill_form

11.Assumption you do the follow code refactor, what is your comment

require 'win32ole'
require 'lib/util/step_util'
require 'watir'
require 'lib/util/web_page_util'

class ExcelUtil
  def getAbsolutePath filename
    fso = WIN32OLE.new('Scripting.FileSystemObject')
    return fso.GetAbsolutePathName(filename)
  end
  def read_step (filename,sheet)
      filename = getAbsolutePath(filename)
      puts filename
      xl = WIN32OLE.new('Excel.Application')
      book = xl.Workbooks.Open(filename)
      record = []
      begin
        sheet = book.Sheets(sheet)
        head = StepUtil.new
        index = 0
        sheet.UsedRange.Rows(1).Cells.each do |cells|
           index+=1
           head.send "column#{index}=",cells.value
        end
          sheet.UsedRange.Rows.each do |row|
           if(row.Cells(1).value!="xpath")
              step = StepUtil.new
              index_1 = 0
             row.Cells.each do |cell|
               index_1+=1
               attr = head.send "column#{index_1}"
               
               step.send "#{attr}=",cell.value
             end
             
            record<<step  
           end
          end
      ensure
        book.Close
        xl.Quit
      end
      return record
    end
    
  def read_example (filename,sheet,ie)
        filename = getAbsolutePath(filename)
        puts filename
        xl = WIN32OLE.new('Excel.Application')
        book = xl.Workbooks.Open(filename)
        record = []
        begin
          sheet = book.Sheets(sheet)
          head = WebPageUtil.new(ie)
          index = 0
          sheet.UsedRange.Rows(1).Cells.each do |cells|
             index+=1
             head.send "column#{index}=",cells.value
          end
            sheet.UsedRange.Rows.each do |row|
             if(row.Cells(1).value!="exampleid")
                example = WebPageUtil.new(ie)
                index_1 = 0
               row.Cells.each do |cell|
                 index_1+=1
                 attr = head.send "column#{index_1}"
                 
                 example.send "#{attr}=",cell.value
               end
               
              record<<example 
             end
            end
        ensure
          book.Close
          xl.Quit
        end
        return record
      end
end


example = ExcelUtil.new
ie = Watir::Browser.new
ie.goto "http://www.google.com"
arr_ex = example.read_example("dos/example_group.xls","product_template",ie)
  arr_ex.each do |example|
    example.fill_form
    puts example       
    puts "_________________________"
  End

12.There is an error in the following code, please correct

require 'rubygems'
require 'active_record'  

ActiveRecord::Base.establish_connection(
    :adapter => "oci", 
    :username => "admin", 
    :password => "123456", 
    :host => "t31a.consys.prognet.com:1839/CTD09.real.com")

    
class Account < ActiveRecord::Base
  set_table_name "ADMIN_TOOL_ACCOUNT"
  set_primary_key "id"
  
end

temp = Account.find_by_user_name("Admin")
puts temp.id
puts temp.USER_NAME

13.Explain how Spec::Mocks work,and give an example
14. In ruby world, who hold object instance variable

A. Kernel  B. Class  C. Object  D. Module

15.Write down "my_method" Method lookup chain

class  A
end

class  B<A
   def my_method
          puts  "do something here"
       end
end

 obj = B.new
  obj.send("my_method")