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nodejs命令行參數處理模塊commander使用實例

   誠然,之前處理都是使用內置的process.agrv ,這個能work,但是不好使,於是tj大神給寫了一個,my god,完全的高大上:

  1、安裝

  代碼如下:

  npm install commander

  2、option 解析

  Options with commander are defined with the .option() method, also serving as documentation for the options. The example below parses args and options from process.argv, leaving remaining args as the program.args array which were not consumed by options.

  代碼如下:

  #!/usr/bin/env node

  /**

  * Module dependencies.

  */

  var program = require('commander');

  program

  .version('0.0.1')

  .option('-p, --peppers', 'Add peppers')

  .option('-P, --pineapple', 'Add pineapple')

  .option('-b, --bbq', 'Add bbq sauce')

  .option('-c, --cheese [type]', 'Add the specified type of cheese [marble]', 'marble')

  .parse(process.argv);

  console.log('you ordered a pizza with:');

  if (program.peppers) console.log(' - peppers');

  if (program.pineapple) console.log(' - pineapple');

  if (program.bbq) console.log(' - bbq');

  console.log(' - %s cheese', program.cheese);

  Short flags may be passed as a single arg, for example -abc is equivalent to -a -b -c. Multi-word options such as “–template-engine” are camel-cased, becoming program.templateEngine etc.

  3、自動生成help信息

  代碼如下:

  $ ./examples/pizza --help

  Usage: pizza [options]

  Options:

  -V, --version output the version number

  -p, --peppers Add peppers

  -P, --pineapple Add pineapple

  -b, --bbq Add bbq sauce

  -c, --cheese Add the specified type of cheese [marble]

  -h, --help output usage information

  當然你也可以手動生成:

  代碼如下:

  #!/usr/bin/env node

  /**

  * Module dependencies.

  */

  var program = require('../');

  function list(val) {

  return val.split(',').map(Number);

  }

  program

  .version('0.0.1')

  .option('-f, --foo', 'enable some foo')

  .option('-b, --bar', 'enable some bar')

  .option('-B, --baz', 'enable some baz');

  // must be before .parse() since

  // node's emit() is immediate

  program.on('--help', function(){

  console.log(' Examples:');

  console.log('');

  console.log(' $ custom-help --help');

  console.log(' $ custom-help -h');

  console.log('');

  });

  program.parse(process.argv);

  console.log('stuff');

  4、舉個完整的例子

  代碼如下:

  function range(val) {

  return val.split('..').map(Number);

  }

  function list(val) {

  return val.split(',');

  }

  function collect(val, memo) {

  memo.push(val);

  return memo;

  }

  function increaseVerbosity(v, total) {

  return total + 1;

  }

  program

  .version('0.0.1')

  .usage('[options] ')

  .option('-i, --integer ', 'An integer argument', parseInt)

  .option('-f, --float ', 'A float argument', parseFloat)

  .option('-r, --range ..', 'A range', range)

  .option('-l, --list ', 'A list', list)

  .option('-o, --optional [value]', 'An optional value')

  .option('-c, --collect [value]', 'A repeatable value', collect, [])

  .option('-v, --verbose', 'A value that can be increased', increaseVerbosity, 0)

  .parse(process.argv);

  console.log(' int: %j', program.integer);

  console.log(' float: %j', program.float);

  console.log(' optional: %j', program.optional);

  program.range = program.range || [];

  console.log(' range: %j..%j', program.range[0], program.range[1]);

  console.log(' list: %j', program.list);

  console.log(' collect: %j', program.collect);

  console.log(' verbosity: %j', program.verbose);

  console.log(' args: %j', program.args);

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