方法说明：

将多个参数组合成一个 path （详细请看例子）

语法：

复制代码 代码如下:

path.join([path1], [path2], [...])

由于该方法属于path模块，使用前需要引入path模块（var path= require(“path”) ）

例子：

复制代码 代码如下:

path.join('/foo', 'bar', 'baz/asdf', 'quux', '..')

// returns

'/foo/bar/baz/asdf'

path.join('foo', {}, 'bar')

// throws exception

TypeError: Arguments to path.join must be strings

源码：

复制代码 代码如下:

// windows version

exports.join = function() {

function f(p) {

if (!util.isString(p)) {

throw new TypeError('Arguments to path.join must be strings');

}

return p;

}

var paths = Array.prototype.filter.call(arguments, f);

var joined = paths.join('');

// Make sure that the joined path doesn't start with two slashes, because

// normalize() will mistake it for an UNC path then.

//

// This step is skipped when it is very clear that the user actually

// intended to point at an UNC path. This is assumed when the first

// non-empty string arguments starts with exactly two slashes followed by

// at least one more non-slash character.

//

// Note that for normalize() to treat a path as an UNC path it needs to

// have at least 2 components, so we don't filter for that here.

// This means that the user can use join to construct UNC paths from

// a server name and a share name; for example:

// path.join('//server', 'share') -> 'servershare')

if (!/^[/]{2}[^/]/.test(paths[0])) {

joined = joined.replace(/^[/]{2,}/, '');

}

return exports.normalize(joined);

};