《objective-c基础教程》学习笔记 （一）—— 开发环境配置和简单类型输出

 1 //
 2 //  main.m
 3 //  ch1
 4 //
 5 //  Created by pcbeta on 14-11-14.
 6 //  Copyright (c) 2014年 julian. All rights reserved.
 7 //
 8 
 9 #import <Foundation/Foundation.h>
10 
11 BOOL areIntsDifferent (int thing1, int thing2)
12 {
13     if (thing1 == thing2)
14     {
15         return (NO);
16     }
17     else
18     {
19         return (YES);
20     }
21 } //最基本的判断两个变量是否不同的函数。如果相同，返回NO；如果不同，返回YES
22 
23 NSString *boolString(BOOL yesNO)
24 {
25     if(yesNO == NO)
26     {
27         return (@"NO");
28     }
29     else
30     {
31         return (@"YES");
32     }
33 } //在函数前面要添加 “＊”号。表示返回的内容是字符串。
34 
35 
36 int main(int argc, const char * argv[])
37 {
38     
39 //    @autoreleasepool {
40 //        
41 //        // insert code here...
42 //        NSLog(@"Hello, World!");
43 //        
44 //    }
45     
46     BOOL areTheyDifferent;
47     int v_thing1 = 5;
48     int v_thing2 = 5;
49     //函数调用
50     areTheyDifferent = areIntsDifferent(v_thing1, v_thing2);
51     //输出结果
52     NSLog(@"Are %d and %d different? %@", v_thing1, v_thing2, boolString(areTheyDifferent));
53     
54     //定义第三个变量
55     int v_thing3 = 10;
56     //重新赋值
57     areTheyDifferent = areIntsDifferent(v_thing1, v_thing3);
58     //输出结果
59     NSLog(@"Are %d and %d different? %@", v_thing1, v_thing3, boolString(areTheyDifferent));
60     
61     return 0;
62 }