Lektion 10: lösningsförslag

1. // 1
2. class Person
3. {
4. private int age;
5. public int Age
6. {
7. get
8. {
9. return age;
10. }
11. set
12. {
13. if (value >= 0)
14. {
15. age = value;
16. }
17. else
18. {
19. throw new ArgumentException("Invalid age");
20. }
21. }
22. }
23. }
25. // 2
26. class Account
27. {
28. private double balance;
30. public void Deposit(double amount)
31. {
32. balance += amount;
33. }
35. public void Withdraw(double amount)
36. {
37. if (amount <= balance)
38. {
39. balance -= amount;
40. }
41. else
42. {
43. throw new ArgumentException("Balance too low");
44. }
45. }
46. }
48. // 2.1
49. class Account2
50. {
51. private double balance;
53. public void Deposit(double amount)
54. {
55. balance += amount;
56. }
58. public void Withdraw(double amount)
59. {
60. if (amount > balance)
61. {
62. balance -= 100;
63. }
64. balance -= amount;
65. }
66. }
68. // 3
69. class SquareLike
70. {
71. private double width;
72. private double height;
74. public SquareLike(double width, double height)
75. {
76. // This calculation can probably be made in a more elegant way (and maybe even a more correct way?), but the details are not relevant for this exercise.
77. if (width / height <= 1.2 && height / width <= 1.2)
78. {
79. // "this" needed to distinguish between argument and field.
80. this.width = width;
81. this.height = height;
82. }
83. else
84. {
85. throw new ArgumentException("Width and height too different");
86. }
87. }
88. }
90. // 3.1
91. class SquareLike2
92. {
93. private double width;
94. private double height;
96. public SquareLike2(double width, double height)
97. {
98. ChangeSize(width, height);
99. }
101. public void ChangeSize(double width, double height)
102. {
103. if (width / height <= 1.2 && height / width <= 1.2)
104. {
105. this.width = width;
106. this.height = height;
107. }
108. else
109. {
110. throw new ArgumentException("Width and height too different");
111. }
112. }
113. }
115. // 4
116. class Temperature
117. {
118. // We choose Celsius as our "canonical" representation.
119. public double Celsius { get; set; }
121. public double Fahrenheit
122. {
123. // We use the 5/9 fraction below for greater accuracy; 0.56 is also fine for our purposes.
124. get
125. {
126. // Convert from Celsius to Fahrenheit.
127. return (Celsius / (5.0 / 9)) + 32;
128. }
129. set
130. {
131. // Convert from Fahrenheit to Celsius.
132. Celsius = (value - 32) * (5.0 / 9);
133. }
134. }
135. }