1.回憶C語言中5大區的地址
(1)棧區
int a=10;
NSLog(@”%p”,&a);
2015-07-28 19:06:00.999 OC10_Block[3922:303] 0x7fff5fbff85c
(2)堆區
int *p=malloc(40);
NSLog(@”%p”,p);
2015-07-28 19:06:01.001 OC10_Block[3922:303] 0x100200500
(3)全局靜態區
static int b=10;
NSLog(@”%p”,&b);
2015-07-28 19:06:01.001 OC10_Block[3922:303] 0x1000023f0
(4)常量區
// 常量字符串:保存常量字符串首字母地址
char *str=”iPhone”;
NSLog(@”%p”,str);
2015-07-28 19:56:14.311 OC10_Block[4272:303] 0x100001f75
(5)代碼區
main.m
import
import
import
import “BaseModel.h”
@implementation BaseModel
-(id)initWithName:(NSString *)name
sex:(NSString *)sex{
self=[super init];
if (self) {
self.name=name;
self.sex=sex;
}
return self;
}
+(id)baseWithName:(NSString *)name
sex:(NSString *)sex{
// 多態的方式完成對象的創建
id obj=[[[self class] alloc] initWithName:name sex:sex];
return obj;
}
@end
// 創建BaseModel 的子類 Person
6.多態
Person *per=[Person baseWithName:@”張三” sex:@”男”];
NSLog(@”%@”,per.sex);
2015-07-28 20:25:41.672 OC10_Block[4581:303] 男
7.數組排序
(1)數組對字符串的排序
[1]不可變數組
NSArray *arr=@[@”zhangsan”,@”lisi”,@”wangermazi”,@”zhaoliu”,@”wangwu”];
// SEL是方法選擇器,它是方法選擇器的類型
NSArray *arrNew=[arr sortedArrayUsingSelector:@selector(compare:)];
NSLog(@”%@”,arrNew);
NSLog(@”%@”,arr);
2015-07-28 20:27:08.687 OC10_Block[4613:303] (
lisi,
wangermazi,
wangwu,
zhangsan,
zhaoliu
)
2015-07-28 20:27:08.689 OC10_Block[4613:303] (
zhangsan,
lisi,
wangermazi,
zhaoliu,
wangwu
)
[2]可變數組
NSMutableArray *arr=[NSMutableArray arrayWithObjects:@”zhangsan”,@”lisi”,@”wangermazi”,@”zhaoliu”,@”wangwu”, nil];
[arr sortUsingSelector:@selector(compare:)];
NSLog(@”%@”,arr);
2015-07-28 20:27:59.836 OC10_Block[4624:303] (
lisi,
wangermazi,
wangwu,
zhangsan,
zhaoliu
)
(2)對對象進行排序
// 新建四個人的對象
Person *per1=[Person baseWithName:@”張三” sex:@”男”];
Person *per2=[Person baseWithName:@”李四” sex:@”男”];
Person *per3=[Person baseWithName:@”王五” sex:@”女”];
Person *per4=[Person baseWithName:@”趙六” sex:@”女”];
[1]不可變數組
// 以學生的姓名作爲排序的依據
// 加個”-“號 降序,否則爲升序
NSArray *arr=@[per1,per2,per3,per4];
NSArray newArr=[arr sortedArrayUsingComparator:^NSComparisonResult(Person obj1, Person * obj2) {
return -[obj1.name compare:obj2.name];
}];
for (Person *per in newArr) {
NSLog(@”%@”,per.name);
}
2015-07-28 20:30:15.080 OC10_Block[4651:303] 趙六
2015-07-28 20:30:15.098 OC10_Block[4651:303] 王五
2015-07-28 20:30:15.099 OC10_Block[4651:303] 李四
2015-07-28 20:30:15.099 OC10_Block[4651:303] 張三
[2]可變數組
// id不改,下面就得轉換
NSMutableArray *arr=[NSMutableArray arrayWithObjects:per1,per2,per3,per4, nil];
[arr sortUsingComparator:^NSComparisonResult(id obj1, id obj2) {
Person per11=(Person )obj1;
Person per22=(Person )obj2;
return [per11.name compare:per22.name];
}];
for (Person *per in arr) {
NSLog(@”%@”,per.name);
}
2015-07-28 20:31:52.934 OC10_Block[4684:303] 張三
2015-07-28 20:31:52.936 OC10_Block[4684:303] 李四
2015-07-28 20:31:52.936 OC10_Block[4684:303] 王五
2015-07-28 20:31:52.937 OC10_Block[4684:303] 趙六