_.now()

93

_.now()

_.now获取从Unix纪元（1970年1月1日）开始一直到现在的经历的时间的毫秒数

参数

返回值

(number): 返回时间戳

例子

_.defer(function(stamp) {
  console.log(_.now() - stamp);
}, _.now());
// => Logs the number of milliseconds it took for the deferred invocation.

源代码：

/**
 * lodash (Custom Build) <https://lodash.com/>
 * Build: `lodash modularize exports="npm" -o ./`
 * Copyright jQuery Foundation and other contributors <https://jquery.org/>
 * Released under MIT license <https://lodash.com/license>
 * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE>
 * Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
 */

/** Detect free variable `global` from Node.js. */
var freeGlobal = typeof global == 'object' && global && global.Object === Object && global;
//检查nodejs环境中的global对象

/** Detect free variable `self`. */
var freeSelf = typeof self == 'object' && self && self.Object === Object && self;
//检查self对象

/** Used as a reference to the global object. */
var root = freeGlobal || freeSelf || Function('return this')();
//对全局对象的引用

/**
 * Gets the timestamp of the number of milliseconds that have elapsed since
 * the Unix epoch (1 January 1970 00:00:00 UTC).
 *
 * @static
 * @memberOf _
 * @since 2.4.0
 * @category Date
 * @returns {number} Returns the timestamp.
 * @example
 *
 * _.defer(function(stamp) {
 *   console.log(_.now() - stamp);
 * }, _.now());
 * // => Logs the number of milliseconds it took for the deferred invocation.
 */
//获取从Unix纪元（1970年1月1日）开始一直到现在的经历的时间的毫秒数
var now = function() {
  return root.Date.now();
};

module.exports = now;