4、编程中的间接性与面向对象编程

编程中的间接性与面向对象编程

1. 变量与代码优化

编程中，添加变量能让代码更简洁、易于扩展。比如，修改循环值时，只需改变变量的值，而无需仔细检查代码中每个具体数字的使用情况。

2. 文件间接性示例：单词长度程序

2.1 Word - Length - 1

该程序打印单词及其长度，代码如下：

#import <Foundation/Foundation.h>
int main (int argc, const char * argv[])
{
    const char *words[4] = { "aardvark", "abacus",
        "allude", "zygote" };
    int wordCount = 4;
    for (int i = 0; i < wordCount; i++) {
        NSLog (@"%s is %lu characters long", words[i], strlen(words[i]));
    }
    return (0);
} // main

运行结果：

aardvark is 8 characters long
abacus is 6 characters long
allude is 6 characters long
zygote is 6 characters long

2.2 Word - Length - 2

当需要更换