javascript怎么判断是否为对象

let obj = {}

typeof obj === Object

// 根据typeof判断对象也不太准确

表达式                       返回值

typeof undefined           'undefined'

typeof null                'object'

typeof true                'boolean'

typeof 123                 'number'

typeof "abc"               'string'

typeof function() {}       'function'

typeof {}                  'object'

typeof []                  'object'