JS 中如何区分空和falsetypeof(undefined) undefined typeof(null) object typeof() stri
JS 中如何区分空和false
typeof(undefined) == 'undefined' typeof(null) == 'object' typeof("") == 'string' typeof(0) == 'number' typeof(false) == 'boolean'记下..
JS 中如何区分空和false
typeof(undefined) == 'undefined' typeof(null) == 'object' typeof("") == 'string' typeof(0) == 'number' typeof(false) == 'boolean'