JavaScript Basic Learning-javascript authoritative Guide-3.5 global objects

Global objects

The properties of the global object can be used directly.

When the JavaScript interpreter starts or any web browser loads a new page, it creates a new global object and gives it a defined set of initial properties:

constructors	description
date	Date object
RegExp	Regular Expression Object
string	string Object
Object	Object Object
Array	object
global object	description
Math	Math class calculation
json	JSON

Global Functions	Description
decodeURI ()	Decodes the URI of an encoding.
decodeURIComponent ()	Decodes a coded URI component.
encodeURI ()	Encodes a string as a URI.
encodeURIComponent ()	Encodes a string as a URI component.
Escape ()	Encodes a string.
Eval ()	Computes the JavaScript string and executes it as script code.
GetClass ()	Returns the Javaclass of a javaobject.
Isfinite ()	Checks if a value is a number that has a poor size.
IsNaN ()	Checks whether a value is a number.
Number ()	Converts the value of an object to a number.
Parsefloat ()	Parses a string and returns a floating-point number.
parseint ()	Parses a string and returns an integer.
String ()	Converts the value of an object to a string.
Unescape ()	Decodes a string encoded by escape ().

Global Properties	Description
Infinity	Represents the numeric value of the positive infinity.
Java	Represents a javapackage at the Java.* package level.
NaN	Indicates whether a value is a numeric value.
Packages	The root Javapackage object.
Undefined	Indicates a value that is not defined.

The Window object acts as a global object in the JavaScript client.

JavaScript Basic Learning-javascript authoritative Guide-3.5 global objects