Prototype attribute interpretation of JS and its common methods

The object-oriented features that JavaScript can implement are: • Public properties (public field) • Publicly available method • Private attribute (private field) • Method overload ( Method overload) • Constructor (constructor) • Event • Single-Inherit • Subclass overrides the parent class's property or method (override) • Static property or method (static member)

Example One (the type of behavior that is allowed to be added in JavaScript): You can use Proptotype on a type to add behavior to a type. These behaviors can only be represented on instances of the type. The allowable types in JS are array, Boolean, Date, Enumerator, Error, Function, number, Object, REGEXP, String

JS Code

1. <script type= "Text/javascript" >
2. Object.prototype.Property = 1;
3. Object.prototype.Method = function ()
4. {
5. Alert (1);
6. }
8. var obj = new Object ();
9. Alert (obj. property);
10. Obj. Method ();
11. </script>

Example two (restrictions used by prototype): prototype cannot be used on an instance, or a compilation error occurs

JS Code

1. <script type= "Text/javascript" >
2. var obj = new Object ();
3. Obj.prototype.Property = 1; //error
4. Error
5. Obj.prototype.Method = function()
6. {
7. Alert (1);
8. }
9. </script>

example three (how to define a static member on a type): You can define a "static" property and method for the type, which is called directly on the type

JS Code

1. <script type= "Text/javascript" >
2. Object.property = 1;
3. Object.Method = function()
4. {
5. Alert (1);
6. }
8. alert (object.property);
9. Object.Method ();
10. </script>

Example Five (): This example demonstrates the usual way to define a type in JavaScript

JS Code

1. <script type= "Text/javascript";
2. function  aclass ()
3. {
4. this . Property = 1;
5. this . Method =&NBSP; function ()
6. {
7. alert (1);
8. }
9. }
10. var  obj =&NBSP; new  aclass ();
11. alert (obj. property);
12. obj. Method ();
13. </script>

example Six (the type of behavior allowed in JavaScript): You can use prototype to add properties and methods to a custom type externally.

JS Code

2. <script type= "Text/javascript" >
4. function AClass ()
6. {
8. this. Property = 1;
10. this. Method = function()
12. {
14. Alert (1);
16. }
18. }
20. Aclass.prototype.Property2 = 2;
22. Aclass.prototype.Method2 = function
24. {
26. Alert (2);
28. }
30. var obj = new aclass ();
32. Alert (obj. Property2);
34. Obj. METHOD2 ();
36. </script>

Example Eight (): You can change properties on an object. (This is yes) you can also change the method on the object. (Different from the universal object-oriented concept)

JS Code

2. <script type= "Text/javascript" >
4. function AClass ()
6. {
8. this. Property = 1;
10. this. Method = function()
12. {
14. Alert (1);
16. }
18. }
20. var obj = new aclass ();
22. Obj. Property = 2;
24. Obj. Method = function()
26. {
28. Alert (2);
30. }
32. Alert (obj. property);
34. Obj. Method ();
36. </script>

Example Nine (): You can add properties or methods on an object

JS Code

2. <script type= "Text/javascript" >
4. function AClass ()
6. {
8. this. Property = 1;
10. this. Method = function()
12. {
14. Alert (1);
16. }
18. }
20. var obj = new aclass ();
22. Obj. Property = 2;
24. Obj. Method = function()
26. {
28. Alert (2);
30. }
32. Alert (obj. property);
34. Obj. Method ();
36. </script>

Example 10 (How to inherit one type from another): This example shows how a type inherits from another type.

JS Code

2. <script type= "Text/javascript" >
4. function AClass ()
6. {
8. this. Property = 1;
10. this. Method = function()
12. {
14. Alert (1);
16. }
18. }
22. function AClass2 ()
24. {
26. this. Property2 = 2;
28. this. Method2 = function()
30. {
32. Alert (2);
34. }
36. }
38. Aclass2.prototype = new aclass ();
42. var obj = new AClass2 ();
44. Alert (obj. property);
46. Obj. Method ();
48. Alert (obj. Property2);
50. Obj. METHOD2 ();
52. </script>

Example 11 (How to redefine a member of a parent class in a subclass): This example shows how subclasses can override the properties or methods of a parent class.

JS Code

2. <script type= "Text/javascript" >
4. function AClass ()
6. {
8. this. Property = 1;
10. this. Method = function()
12. {
14. Alert (1);
16. }
18. }
22. function AClass2 ()
24. {
26. this. Property2 = 2;
28. this. Method2 = function()
30. {
32. Alert (2);
34. }
36. }
38. Aclass2.prototype = new aclass ();
40. AClass2.prototype.Property = 3;
42. AClass2.prototype.Method = function()
44. {
46. Alert (4);
48. }
50. var obj = new AClass2 ();
52. Alert (obj. property);
54. Obj. Method ();
56. </script>

Prototype attribute interpretation of JS and its common methods