has

key

Signature

has.key (obj, key)

Description

Check if an object has a specific own property. Throws a TypeError if obj is not a plain object or key is not a string.

Parameters

Name	Type	Required	Description
obj	object	yes	The object to check
key	string	yes	The property name to look for

Returns

Type	Description
boolean	True if the object has the specified own property

Examples

has.key({ name: 'Alice' }, 'name') // true
has.key({ name: 'Alice' }, 'age')  // false
has.key({ name: null }, 'name')    // true

keys

Signature

has.keys (obj, keys)

Description

Check if an object has all of the specified own properties. Throws a TypeError if obj is not a plain object or keys is not a non-empty array of strings.

Parameters

Name	Type	Required	Description
obj	object	yes	The object to check
keys	string[]	yes	Array of property names to look for

Returns

Type	Description
boolean	True if the object has all the specified own properties

Examples

has.keys({ name: 'Alice', age: 25 }, ['name', 'age']) // true
has.keys({ name: 'Alice' }, ['name', 'age'])           // false
has.keys({ name: 'Alice', age: 25 }, ['name'])         // true

keyWithValue

Signature

has.keyWithValue (obj, key)

Description

Check if an object has a specific own property and its value is defined (not null or undefined).

Parameters

Name	Type	Required	Description
obj	object	yes	The object to check
key	string	yes	The property name to look for

Returns

Type	Description
boolean	True if the object has the property and its value is not null or undefined

Examples

has.keyWithValue({ name: 'Alice' }, 'name')  // true
has.keyWithValue({ name: null }, 'name')      // false
has.keyWithValue({ name: undefined }, 'name') // false
has.keyWithValue({ age: 25 }, 'name')         // false