1. #import <Foundation/Foundation.h>
   
2. #import "Student.h"
   
3. 
   
4. int main(int argc, const char * argv[])
   
5. {
   
6.     Student *p1 = [[Student alloc] initWithName:@"Jim" andAge:18 andScore:78];
   
7.    
   
8.    
   
9. //    Student *p2 = [[Student alloc] initWithName:@"Jack" andAge:19 andScore:82];
   
10. //   
    
11. //    Student *p3 = [[Student alloc] initWithName:@"May" andAge:17 andScore:99];
    
12. //   
    
13. //    Student *p4 = [[Student alloc] initWithName:@"Lily" andAge:18 andScore:60];
    
14. //   
    
15. //    Student *p5 = [[Student alloc] initWithName:@"Candy" andAge:18 andScore:75];
    
16.    
    
17.    
    
18.    
    
19.    
    
20.     NSLog(@"%@",p1);
    
21.    
    
22.    
    
23.    
    
24.    
    
25. //    [p1 release];
    
26. //    [p2 release];
    
27. //    [p3 release];
    
28. //    [p4 release];
    
29. //    [p5 release];
    
30.    
    
31.     return 0;
    
32. }
    
33. 
    
34. #import <Foundation/Foundation.h>
    
35. 
    
36. @interface Student : NSObject
    
37. {
    
38.     int _age;
    
39.     int _score;
    
40.     NSString *_name;
    
41. }
    
42. //年龄 分数 姓名的get  set
    
43. -(void)setAge:(int)age;
    
44. -(int)age;
    
45. 
    
46. -(void)setScore:(int)score;
    
47. -(int)score;
    
48. 
    
49. -(void)setName:(NSString *)name;
    
50. -(NSString *)name;
    
51. 
    
52. //快速构造器的声明
    
53. -(id)initWithName:(NSString *)name andAge:(int)age andScore:(int)score;
    
54. 
    
55. 
    
56. @end
    
57. 
    
58. 
    
59. #import "Student.h"
    
60. 
    
61. @implementation Student
    
62. 
    
63. //年龄 分数 姓名的set get的实现
    
64. -(void)setAge:(int)age
    
65. {
    
66.     _age = age;
    
67. }
    
68. -(int)age
    
69. {
    
70.     return _age;
    
71. }
    
72. 
    
73. 
    
74. -(void)setScore:(int)score
    
75. {
    
76.     _score = score;
    
77. }
    
78. -(int)score
    
79. {
    
80.     return _score;
    
81. }
    
82. 
    
83. 
    
84. -(void)setName:(NSString *)name
    
85. {
    
86.     if ( name != _name)
    
87.     {
    
88.         [_name release];
    
89.         _name = [name retain];
    
90.     }
    
91. }
    
92. -(NSString *)name
    
93. {
    
94.     return _name;
    
95. }
    
96. 
    
97. //输出整个学生信息
    
98. - (NSString *)description
    
99. {
    
100.     return [NSString stringWithFormat:@"My Name Is %@,Age Is %d.Score Is %d.",_name,_age,_score];
     
101. }
     
102. 
     
103. //快速构造器的实现
     
104. -(id)initWithName:(NSString *)name andAge:(int)age andScore:(int)score
     
105. {
     
106.     if ( self = [super init])
     
107.     {
     
108.         _name = name;
     
109.         _age = age;
     
110.         _score = score;
     
111.     }
     
112.     return  self;
     
113. }
     
114. @end
     

复制代码

ndefined symbols for architecture x86_64:
  "_OBJC_CLASS_$_Student", referenced from:
      objc-class-ref in main.o
ld: symbol(s) not found for architecture x86_64
clang: error: linker command failed with exit code 1 (use -v to see invocation)


网上说是用第三方框架什么的，但是我什么都没用啊，这个怎么回事？

为嘛你的成员变量也要relsase？

温天恩 发表于 2014-7-19 23:21
为嘛你的成员变量也要relsase？

name是字符串，在OC里是对象。所以要release

为什么我换个文件，同样的代码又可以了？这是为什么？

Moebius 发表于 2014-7-19 23:54
name是字符串，在OC里是对象。所以要release

假如你初始化NSString时候没有用alloc，就不用release。