AS的开发者之一timcharper声明已经在6月18日修好了这个问题。

def export_csv
# find_page is how the List module gets its data. see Actions::List#do_list.
records = find_page().items
return if records.size == 0

# Note this code is very generic. We could move this method and the
# action_link configuration into the ApplicationController and reuse it
# for all our models.
data = “”
cls = records[0].class
data << cls.csv_header << “\r\n”
records.each do |inst|
data << inst.to_csv < ‘text/csv’, :filename => cls.name.pluralize + ‘.csv’
end
end
在model中：
class User < ActiveRecord::Base
…

# The header line lists the attribute names. ID is quoted to work
# around an issue with Excel and CSV files that start with “ID”.
def self.csv_header
“”ID”,Last Name,First Name,Email,Birthdate”
end

# Emit our attribute values as a line of CSVs
def to_csv
id.to_s << “,” << last_name << “,” << first_name << “,” << email <<
“,” << birthdate.to_s
end
end
因为几乎每个表都要打印，在控制器中直接写到application中就可以了。而在model中要把每个字段都列出来，好像有点麻烦。而且在字段值为空的时候会报错。
有没有什么好的方法？