问题描述
options.filename = dbPath+’picker’; pickerDB = new Datastore(options); options.filename = dbPath+’data’; dataDB = new Datastore(options); options.filename = dbPath+’web’; webDB = new Datastore(options); options.filename = dbPath+’url’; urlDB = new Datastore(options); options.filename = dbPath+’attach’; attachDB = new Datastore(options); options.filename = dbPath+’cacheUrl’; cacheUrlDB = new Datastore(options); options.filename = dbPath+’cache’; cacheDB = new Datastore(options); options.filename = dbPath+’cron’; cronDB = new Datastore(options); options.filename = dbPath+’log’; logDB = new Datastore(options); options.filename = dbPath+’cronLog’; cronLogDB = new Datastore(options);
请教一下，这一大段，都是复制粘贴。能用更简洁的代码一次搞定吗？
问题解答
回答1：不知道算不算你心中的简写，我觉得从重复的角度看，把不同的部分提取出来做个数组，把相同的部分抽象，如下：
let options = {}, dbPath = ’’; //TBD by yourselflet stores = [ ’picker’, ’data’, ’web’, ’url’, ’attach’, ’cacheUrl’, ’cache’, ’cron’, ’log’, ’cronLog’] .map(key => (options.filename = dbPath + key, new Datastore(options)));console.log(stores); //stores you want回答2：
/*options == ?dbPath == ? */ var _Datastore = {}; _Datastore._opts = options; _Datastore._path = dbPath; _Datastore.Create = function(pathAddon){this._opts.filename = this._path + pathAddon;return new Datastore(this.options); };pickerDB = _Datastore.Create(’picker’); dataDB = _Datastore.Create(’data’); webDB = _Datastore.Create(’web’); urlDB = _Datastore.Create(’url’); attachDB = _Datastore.Create(’attach’); cacheUrlDB = _Datastore.Create(’cacheUrl’); cacheDB = _Datastore.Create(’cache’); cronDB = _Datastore.Create(’cron’); logDB = _Datastore.Create(’log’); cronLogDB = _Datastore.Create(’cronLog’);
不知道你接下来的代码怎么用？如果后边的逻辑代码好改，可以改成：
var _Datastore = {}; _Datastore._opts = options; _Datastore._path = dbPath; _Datastore._cache = {}; _Datastore.Create = function(pathAddon){this._opts.filename = this._path + pathAddon;return new Datastore(this.options); }; _Datastore.DB = function(pathAddon){this._cache[pathAddon] = this._cache[pathAddon] || this.Create(pathAddon);return this._cache[pathAddon]; };//调用 cronLogDB 时 改成 _Datastore.DB(’cronLog’);//第一次 会创建，第二次直接用之前创建的实例
