1. The new keyword in JavaScript is used to create an instance of an object and link it to a constructor function. It sets the object's internal [[Prototype]] property to the constructor function's prototype property. 2. The prototype property allows methods and properties to be shared among all instances of objects created with a constructor function. Changes to the prototype property are visible to all object instances. 3. In older versions of Internet Explorer, the __proto__ property serves a similar purpose to the prototype property for sharing properties among objects, but __proto__ has been deprecated and prototype should be used instead.

2. 1.

6. var a= b

7. new

8. var a = new String(“text”);

9. var a = new String(“text”);
• new
• new
String

10. String
new

11. new

12. this

14. function test(x,y){
this.x = x;
this.y = y;
}
var a = new test(1,2);
new test(1,2) test
new
new this

15. this

17. var a= obj;
a obj

18. this

19. this=

24. •
• function(){
…
}
•
•

25. var test = function(x,y){
this.x = x;
this.y = y;
};
function test(x,y){
this.x = x;
this.y = y;
}

28. var test = function(){
this.a = “abc”;
};
test.text = “ ”;
test.text2 = “ ”;

30. new

31. new

32. test

33. var test = function(){
this.a = "abc";
};
test.text = " ";
var a = new test();
console.log(a.a);
console.log(text.text);
console.log(a.text);

35. text

36. this
text

37. new

41. prototype

42. prototype

43. prototype

45. constructor
prototype

46. var test = function(){
this.a = "abc";
};
//test.prototype
test.prototype = {
constructor:function(){
this.a= "abc"
},
__proto__:Object //IE
};

48. __proto__
prototype
IE __proto__

49. prototype
new
prototype

54. a.text = "1234"
a text

55. 2.

58. var a = {
abc:"text"
};
{}

59. new

61. prototype
new

62. var test = {
test : "text"
};
var Creator = function(){};
Creator.prototype = test;
var a = new Creator();
console.log(a.test);//text

63. CSS cascade

64. new

65. jQuery

66. • new
• prototype
• prototype
• prototype
•
prototype