ruby文件读取写入相关操作

http://www.cnblogs.com/cnblogsfans/archive/2009/09/19/1569918.html

http://www.cnblogs.com/cnblogsfans/archive/2009/09/17/1568804.html

二、读取文件

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print?

1
file=File.open(File.join("C:","Test.txt"),"r")

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

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file.close

一、新建文件

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print?

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

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f.puts("I am Jack")

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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 exists; otherwise, creates a new file for writing.

"a+" ：Read-write. Starts at end of file if file exists; otherwise, 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