A class is a specific subdivision of an object, and an instance is a specific thing in a class.
Basic data types and reference data types
Basic data type: numble string undefined null
Reference data types: objects and functions
The object data type is also subdivided into: object Class (Objects) array class (array) regular Class (REG). )
Characteristics of basic data types: operation by value
Characteristics of reference data types: first open a space, the browser assigns it an address, then saves the content in space, and finally assigns the address to the variable.
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How objects are created
1. Literal type
var obj={}
Cases:
var person={
Name= "Li Xiao Jing",
Age=24
};
How instances are created
var obj=new Object ();
Obj.name= "LXJ";
obj.age=24;
}
The distinguished data type of the object class instance in JS Create object