我只是希望有人可以提供以下代码来帮助我：

def write(aFile,number)
  index = 1
  while (index < number)
   aFile.puts(index.to_s)
   index += 1
  end
end

def read(aFile)

  count = aFile.gets
  if (is_numeric?(count))
    count = count.to_i
  else
    count = 0
    puts "Error: first line of file is not a number"
  end

  index = 0
  while (count < index)
    line = aFile.gets
    puts "Line read: " + line
  end
end

# Write data to a file then read it in and print it out
def main
  aFile = File.new("mydata.txt","w") 
  if aFile  
    write(aFile,11)
    aFile.close
  else
    puts "Unable to open file to write!"
  end

  aFile = File.new("mydata.txt","r") 
  if aFile
    read(aFile)
    aFile.close
  else
    puts "Unable to open file to read!"
  end
end

# returns true if a string contains only digits
def is_numeric?(obj)
  if /[^0-9]/.match(obj) == nil
    true
  end
  false
end

main

我想要得到的结果是：

Line read: 0

Line read: 1

...

Line read: 10

但是我得到：

Error: first line of file is not a number

为什么会这样？我的代码一定有问题。