javacript实现类继承的几种方法

<script type="text/javascript">

2 //------------------对象冒充实现继承-----------------

3 function ClassA(sColor)

4 {

5 this.color=sColor;

6 this.showColor=function()

7 {

8 alert(this.color);

9 }

10 }

11 function ClassC(iBig)

12 {

13 this.color=iBig;

14 this.showBig=function()

15 {

16 alert(this.color);

17 }

18

19 }

20 function ClassB(sColor,sName,iBig)

21 {

22 this.newMethed=ClassA;

23 this.newMethed(sColor);

24 delete this.newMethed;

25

26 this.newMethed=ClassC;

27 this.newMethed(iBig);

28 delete this.newMethed;

29

30 this.name=sName;

31 this.sayName=function()

32 {

33 alert(this.name);

34 }

35 }

36 //var oCarA=new ClassA("red");

37 //oCarA.showColor();

38 var oCarB=new ClassB("blue","myTest",100);

39 oCarB.showColor();

40 oCarB.showBig();

41 oCarB.sayName();

42 //----------------call或apply方法实现继承---------------------

43 function ClassA(sColor)

44 {

45 this.color=sColor;

46 this.showColor=function()

47 {

48 alert(this.color);

49 }

50 }

51 function ClassB(sColor,sName)

52 {

53 //this.newMethed=ClassA;

54 //this.newMethed(sColor);

55 //delete this.newMethed;

56 //ClassA.call(this,sColor);

57 //ClassA.apply(this,new Array(sColor));

58 ClassA.apply(this,arguments);

59

60 this.name=sName;

61 this.sayName=function()

62 {

63 alert(this.name);

64 }

65 }

66 var oCarB=new ClassB("blue","myTest");

67 oCarB.showColor();

68 oCarB.sayName();

69 //-------------------原型链实现继承------------------------

70 function ClassA(){}

71 ClassA.prototype.color="red";

72 ClassA.prototype.showColor=function()

73 {

74 alert(this.color);

75 }

76 }

77 function ClassB(){}

78

79 ClassB.prototype=new ClassA();

80 ClassB.prototype.name="smatt";

81 ClassB.prototype.showName=function()

82 {

83 alert(this.name);

84 }

85 var oCar=new ClassB();

86 oCar.showColor();

87 oCar.showName();

88 //----------------------混合方式实现继承-----------------------------

89 function ClassA(sColor)

90 {

91 this.color=sColor;

92 }

93 ClassA.prototype.showColor=function()

94 {

95 alert(this.color);

96 }

97 function ClassB(sColor,sName)

98 {

99 ClassA.call(this,sColor);

100 this.name=sName;

101 }

102 ClassB.prototype=new ClassA();

103 ClassB.prototype.showName=function()

104 {

105 alert(this.name);

106 }

107 var oCar=new ClassB("red","smatt");

108 oCar.showColor();

109 oCar.showName();

110

111 </script>