如果第一行后跟一个空行,Ruby CSV不会找到文件头 [英] Ruby CSV doesn't find file headers if first line is followed by an empty one
问题描述
我遇到了一个奇怪的问题,我的脚本不能在一些CSV文件上工作。问题是以下,我需要访问列名称(文件头)来正确处理文件。我一直在使用以下(测试)代码列出标题:
I have encountered an odd issue where my script wouldn't work on some CSV files. Problem is the following, I need to access the column names (file headers) to properly process the file. I've been using the following (test) code to list the headers :
CSV file = CSV.read(argument, :headers => true)
if file.headers() == nil
puts "According to the doc : Headers will not be used"
elsif file.headers() == true
puts "According to the doc : Headers will be used, but not read yet"
else
puts "Headers were read, this is an array : #{file.headers.to_s}"
end
现在,应用于第一个csv:
Now, applied to the first csv :
key,fr
edit,Éditer
close,Fermer
我得到:
Headers were read, this is an array : ["key", "fr"]
但是,如果我知道在标题和内容之间添加一个空行如下:
But, if I know add an empty line between the headers and the content itself, like so :
key,fr
edit,Éditer
close,Fermer
它不再工作:
Headers were read, this is an array : []
这让我很生气。这是预期的行为吗?有什么我能做的吗?我一直在阅读ruby CSV文件,但找不到任何东西。
它可能是一些csv文件规格我不知道?
在ruby 1.9.3和2.1.1上测试
This baffles me. Is this expected behavior ? Is there anything I can do about it ? I've been reading the ruby CSV doc but cannot find anything. Could it be some csv file specs I don't know about ? Tested on ruby 1.9.3 and 2.1.1
推荐答案
添加选项:skip_blanks =>
Add the option :skip_blanks => true
when you are reading the CSV file.
file = CSV.read(path, :headers => true,:skip_blanks => true)
此选项:skip_blanks => true
,将跳过所有这样的空行,如果你有任何现在,你会得到正常的输出。
This option :skip_blanks => true
, will skip all such blank lines if any present like you are having, and you will get the normal output.
这里是我的尝试同样:
require 'csv'
content = <<_
key,fr
edit,Éditer
close,Fermer
_
File.write('test',content)
file = CSV.read('test', :headers => true,:skip_blanks => true)
if file.headers() == nil
puts "According to the doc : Headers will not be used"
elsif file.headers() == true
puts "According to the doc : Headers will be used, but not read yet"
else
puts "Headers were read, this is an array : #{file.headers.to_s}"
end
# >> Headers were read, this is an array : ["key", "fr"]
你说,我也同意你,下面一个:
Working correctly as you said, and I also agreed with you, below one :
require 'csv'
content = <<_
key,fr
edit,Éditer
close,Fermer
_
File.write('test',content)
file = CSV.read('test', :headers => true)
file.headers # => ["key", "fr"]
file.to_a # => [["key", "fr"], ["edit", "Éditer"], ["close", "Fermer"]]
当您设置:headers => true
是CSV数据的第一行,您将会看到标题。考虑到这个定义,上面的内容很好。但下面一个矛盾:
When you set :headers => true
, the first row of the CSV data, you have will be tread as header. With this definition in mind, The above goes well. But the below one contradicts :
require 'csv'
File.write('test',content)
file = CSV.read('test', :headers => true)
file.headers # => ["key", "fr"]
file.to_a # => [["key", "fr"], ["edit", "Éditer"], ["close", "Fermer"]]
content = <<_
key,fr
edit,Éditer
close,Fermer
_
File.write('test1',content)
file = CSV.read('test1', :headers => true)
file.headers # => [] # <~~~~~~~~~~~ Is this a bug ?
file.to_a # => [[], [], ["edit", "Éditer"], ["close", "Fermer"]]
b $ b
file.headers
给出一个空数组 []
,你可以看到, strong> 0 th 输出 file.to_a
的索引也是一个空数组( []
)。但它似乎是一个错误。因此,我提出了 。
file.headers
gives an empty array []
, as you can see that in the 0th index of the output of file.to_a
is also an empty array([]
). But it seems to a bug. Thus I raised the issue.
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