nodejs命令行参数处理模块commander使用实例_node.js

1、安装

代码如下:
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.

代码如下:
#!/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、自动生成help信息

代码如下:
$ ./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

当然你也可以手动生成：
代码如下:
#!/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、举个完整的例子

代码如下:
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);