Python command line parameter parsing module Optparse use instance _python

Example

Copy Code code as follows:

From Optparse import Optionparser
[...]
def main ():
Usage = "Usage:%prog [options] arg"
Parser = Optionparser (usage)
Parser.add_option ("F", "--file", dest= "filename",
help= "read data from FILENAME")
Parser.add_option ("-V", "--verbose",
Action= "Store_true", dest= "verbose")
Parser.add_option ("Q", "--quiet",
Action= "Store_false", dest= "verbose")
[...]
(options, args) = Parser.parse_args ()
If Len (args)!= 1:
Parser.error ("Incorrect number of arguments")
If Options.verbose:
Print "Reading%s ..."% Options.filename
[...]

if __name__ = = "__main__":
Main ()

Add Options (Add_option ())

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Optionparser.add_option (option)
Optionparser.add_option (*opt_str, Attr=value, ...)

Define short options

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Parser.add_option ("F", Attr=value, ...)

Define long Options

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Parser.add_option ("–foo", Attr=value, ...)

If you define

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Parser.add_option ("F", "--file", action= "store", type= "string", dest= "filename")

The command line format can have the following form

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-ffoo
-F foo
--file=foo
--file Foo

After parsing results

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Options.filename = "Foo"

Parsing (Parse_args ())

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(options, args) = Parser.parse_args ()

Options parsed parameters, saved in dictionary form
Args arguments that cannot be resolved, saved as a list

Behavior (Action)

Store default behavior, save value to Dest
"Store_const" Save constants
"Append" append this option ' s argument to a list
"Count" increment a counter by one
"Callback" call a specified function

Set defaults (default)

Copy Code code as follows:

Parser.add_option ("-V", action= "Store_true", dest= "verbose", default=true)
Parser.set_defaults (Verbose=true)

Generate Help Tips

The Help option is available and can be printed with parser.print_help ()

Copy Code code as follows:

Parser.add_option ("F", "–file", dest= "filename", help= "write to File", metavar= "file")

set a Boolean value

Support for Store_true and store_false two behaviors

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Parser.add_option ("-V", action= "Store_true", dest= "verbose")
Parser.add_option ("Q", action= "Store_false", dest= "verbose")

If you encounter-v,verbose=true; if you encounter-q,verbose=false

Error handling

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(options, args) = Parser.parse_args ()
[...]
If OPTIONS.A and options.b:
Parser.error ("Options-a and-b are mutually exclusive")

option group (Grouping options)

Format is as follows

Class Optparse. OptionGroup (parser, title, Description=none)

Copy Code code as follows:

Group = OptionGroup (parser, "Dangerous Options",
"Caution:use options at your own risk. "
"It is believed that some of them bite.")
Group.add_option ("G", action= "Store_true", help= "Group option.")
Parser.add_option_group (Group)

The results of the prompts are as follows

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Usage: <yourscript> [options] arg1 arg2

Options:
-H,--help show this Help and exit
-V,--verbose make lots of noise [default]
-Q,--quiet be vewwy quiet (I ' m hunting wabbits)
-F FILE,--filename=file
Write output to FILE
-M MODE,--mode=mode interaction mode:novice, intermediate, or
Expert [Default:intermediate]

Dangerous Options:
Caution:use options at your own risk. It is believed that some
of them bite.

-G Group option.