文件中读取：一次读入全部(设置headers使 CSV#shift() 以CSV::Row对象返回而不是数组；使

require'csv'CSV#read() 返回 CSV::Table 对象而不是数组)CSV.read('test.csv')#=>Array#headers默认为false，如果设置为true，csv的第一行将被视为标题CSV.read('test.csv',headers:true)#=>CSV::Table#headers设置为数组，这个数组将被作为标题CSV.read('test.csv',headers:[1,2,3,4,5])#headers设置为字符串，这个字符串内容将被作为标题CSV.read('test.csv',headers:"1,2,3,4,5")

​ 文件中读取：一次读入一行

#由于headers配置，返回类型发生变化（这个方法默认为第一行是标题，不会进行返回）CSV.foreach'test.csv'do|row|puts row.class#=>ArrayendCSV.foreach('test.csv',headers:true)do|row|puts row.class#=>CSV::Rowend#return_headers:true 返回标题CSV.foreach('test.csv',return_headers:true)do|row|p row#=>返回Arrayend

​ 字符串中读取：一次读取一行

CSV.parse("CSV,data,String")do|row|# use row here...end

​ 字符串中读取：全部读取

CSV.parse("CSV,data,String")#[]方法需要返回的类型为CSV::ROW所以设置参数headers:truecontent = File.read('data.csv') csv = CSV.parse(content,headers:true) sum =0csv.eachdo|row|sum += row['id'].to_iendputs sum

命令行调用rb文件（假设ruby.exe加入了环境变量）：xxx>ruby xx/xx.rb yy/yy.txt

则该参数(yy/yy.rb)通过命令行传给了Ruby解释器，且解释器会将yy/yy.rb赋值给 ARGV[0](ARGV是一个数组常量)，所以可以在程序中引用ARGV[0]来获取命令行中传入的路径(yy/yy.txt)

xx.rb文件可以这样开始：

txt_path = ARGV[0]

#异常处理，判断txt_path是否合法，略！！

text = IO.read(txt_path)

#以下为对文本text的分析.....

f=File.new(File.join("C:","Test.txt"), "w+")

f.puts("I am Jack")

f.puts("Hello World")

文件模式

"r" ：Read-only. Starts at beginning of file (default mode).

"r+" ：Read-write. Starts at beginning of file.

"w" ：Write-only. Truncates existing file to zero length or creates a new file for writing.

"w+" ：Read-write. Truncates existing file to zero length or creates a new file for reading and writing.

"a" ：Write-only. Starts at end of file if file existsotherwise, creates a new file for writing.

"a+" ：Read-write. Starts at end of file if file existsotherwise, creates a new file for reading and writing.

"b" ：(DOS/Windows only.) Binary file mode. May appear with any of the key letters listed above

二、读取文件

file=File.open(File.join("C:","Test.txt"),"r")

file.each { |line| print "#{file.lineno}.", line }

file.close

三、新建、删除、重命名文件

File.new( "books.txt", "w" )

File.rename( "books.txt", "chaps.txt" )

File.delete( "chaps.txt" )

四、目录操作

1     创建目录

Dir.mkdir("c:/testdir")

04     #删除目录

05     Dir.rmdir("c:/testdir")

07     #查询目录里的文件

08     p Dir.entries(File.join("C:","Ruby")).join(' ')

10     #遍历目录

11     Dir.entries(File.join("C:","Ruby")).each {

|e| puts e

}

1、ARGV and ARGF

ARGV

ARGV <<"cnblogslink.txt"

#The gets method is a Kernel method that gets lines from ARGV

print while gets

p ARGV.class

ARGF

while line = ARGF.gets

print line

end

2、文件信息查询

#文件是否存在

p File::exists?( "cnblogslink.txt" ) # =>true

#是否是文件

p File.file?( "cnblogslink.txt" ) # =>true

#是否是目录

p File::directory?( "c:/ruby" ) # =>true

p File::directory?( "cnblogslink.txt" ) # =>false

#文件权限

p File.readable?( "cnblogslink.txt" ) # =>true

p File.writable?( "cnblogslink.txt" ) # =>true

p File.executable?( "cnblogslink.txt" ) # =>false

#是否是零长度

p File.zero?( "cnblogslink.txt" ) # =>false

#文件大小 bytes

p File.size?( "cnblogslink.txt" ) # =>74

p File.size( "cnblogslink.txt" ) # =>74

#文件或文件夹

p File::ftype( "cnblogslink.txt" ) # =>"file"

#文件创建、修改、最后一次存取时间

p File::ctime( "cnblogslink.txt" ) # =>Sat Sep 19 08:05:07 +0800 2009

p File::mtime( "cnblogslink.txt" ) # =>Sat Sep 19 08:06:34 +0800 2009

p File::atime( "cnblogslink.txt" ) # =>Sat Sep 19 08:05:07 +0800 2009

3、查找文件

puts "查找目录下所有文件及文件夹"

Dir["c:/ruby/*"].each {|x|

puts x

}

puts "条件查询"

Dir.foreach('c:/ruby') {

|x| puts x if x != "." &&x != ".."

}

puts "查找某一类型文件"

Dir["*.rb"].each {|x|

puts x

}

puts "Open 查询"

Dir.open('c:/ruby') { |d| d.grep /l/ }.each{|x| puts x}

puts "---------------------------"

puts "正则表达式查询"

Dir["c:/ruby/ruby/[rs]*"].each{|x| puts x}

puts "------------------------"

Dir["c:/ruby/[^s]*"].each{|x| puts x}

puts "------------------------"

Dir["c:/ruby/{ruby,li}*"].each{|x| puts x}

puts "------------------------"

Dir["c:/ruby/?b*"].each{|x| puts x}

puts "查找目录及子目录的文件"

require 'find'

Find.find('./') { |path| puts path }

3、查询目录及子目录文件

require "find"

Find.find("/etc/passwd", "/var/spool/lp1", ".") do |f|

Find.prune if f == "."

puts f

end

原型：ref.find( [ aName ]* ) {| aFileName | block }

prune：Skips the current file or directory, restarting the loop with the next entry. If the current file is a directory, that directory will not be recursively entered. Meaningful only within the block associated with Find::find.

4、文件比较 复制等

require 'ftools'

File.copy 'testfile', 'testfile1'  » true

File.compare 'testfile', 'testfile1'  » true