Objective-C笔记大全
Posted Johnay_xiao
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1.0 Basic Operations
srand((unsigned)time(0)); //种种子
int index = arc4random() % poker.allCads.count;//不需要种子取随机数
[p retain]; //查看引用计数值
__weak => [p release]; p = nil; //不能分配空间,马上释放1.1 CopyWithZone
- (id)copyWithZone:(NSZone *)zone {
Integer *i = [[Integer allocWithzone:zone] initWithInteger:self.ingeger];
return i;
}1.2 The judgement of class
- [square isKindOfClass:[TRSquare class]] == YES; //判断是否为子类对象
- [square isMemberOfClass:[TRSquare class]] == YES; //判断是否为成员对象
- [square isSubClassOfClass:[TRSquare class]] == YES; //判断是否为子类
- SEL sel = @selector(study)
- [Student instancesRespondToSelector:sel] == YES //判断类中是否有指定方法
- [stu respondsToSelector:@selector(learn)] == YES //判断对象能否调用指定方法
- [stu performSelector:sel] => [stu study] //执行方法1.3 Protocol
- Protocol *p = @protocol(NSCopying);
- [Student conformsToProtocol:p] == YES //判断是否采纳指定协议1.4 NSString
- [str substringToIndex:3]; //截取头,截取从下标0到3的字符
- [str substringFromIndex:10] //截取尾,截取下标10以后的字符
- [str substngWithRange:NSMakeRange(4,4)]; //范围截取,从下标4开始截取4个字符
- str = [str1 stringByAppendingString:str2]; //字符串拼接
- str = [str1 stringByAppendingFormat:@"%@%d",str2,i]; //格式化追加
- str = [str1 stringByReplacingCharactersInRange:NSMakeRange(4,10) withString:@"tedu"]; //指定范围替换
- str = [NSString stringWithContentOfFile:filePath encoding:NSUTF8StringEncoding error:nil]; //文件内容初始化字符串
- str = [NSString stringWithCString:CString encoding:NSASCIIStringEncoding]; //C字符串转为OC字符串
1.5 NSMutableString
- [NSMutableString stringWithcapacity:100]; //预估值初始化
- [NSMutableString stringWithString:@"string"]; //标准化初始化
- [NSMutableString stringWithFormat:@"age:%d",age]; //标准格式化
- [str appendString:@"The String"]; //追加
- [str appendFormat:@"have %lucharacters.",str.length]; //格式化追加
- NSRange range = [str rangeOfString:@"Objective-"];
- [str deleteCharactersInRange:range]; //指定范围删除
- [str replaceCharactersInRange:[str rangeOfString:@"a"] withString:@"another"]; //指定字符串替换
1.6 Packaging & Unpackaging
- NSNumber *i = [NSNumber numberWithInt:a];//封装
- int b = [i intValue];//拆封
- NSNumber *c = [NSNumber numberWithChar:ch];
- char ch1 = [c charValue];
- NSNumber *d1 = [NSNumber numberWithDouble:d];
- double d2 = [d1 doubleValue];
- NSNumber *f1 = [NSNumber numberWithFloat:f];
- float f2 = [f1 floatValue];
- NSNumber *b2 = [NSNumber numberWithBool:b1];
- BOOL b3 = [b2 boolValue];1.7 NSValue
typedef struct
{
int x;
int y;
}TRPoint;
typedef struct
{
char ch;
double d;
}TRMyData;
int main(int argc, const char * argv[]) {
@autoreleasepool {
TRPoint p;
p.x = 10;//0xA
p.y = 15;//0xF
NSValue *value = [NSValue valueWithBytes:&p objCType:@encode(TRPoint)];//封装
NSLog(@"%@", value);
TRPoint p1;
[value getValue:&p1];//拆封
NSLog(@"(%d,%d)", p1.x, p1.y);
TRMyData data = {‘a‘, 3.14};
NSValue *md = [NSValue valueWithBytes:&data objCType:@encode(TRMyData)];
TRMyData data1;
[md getValue:&data1];
NSLog(@"%c,%g", data1.ch, data1.d);
}
return 0;
}1.8 Description
- NSLog(@"%@", teacher); //输出teacher对象,自动调用重写的description方法
-(NSString *)description
{
return [NSString stringWithFormat:@"姓名：%@，课程：%@", self.name, self.course];
}
1.9 NSData
#获取世界标准时间
NSDate *date = [NSDate date];
#获取本地时间方法一
NSTimeZone *zone = [NSTimeZone systemTimeZone];
NSInteger integer = [zone secondsFromGMTForDate:[NSDate date]];
NSDate *localDate = [[NSDate date] dateByAddingTimeInterval:integer];
#获取本地时间方法二
NSDate *localDate = [[NSDate date] dateByAddingTimeInterval:8*3600];
#获取本地时间方法三
NSDate *date1 = [NSDate dateWithTimeIntervalSinceNow:8*3600];
#格式化本地时间方法
NSDateFormatter *dateformatter = [[NSDateFormatter alloc] init];
dateformatter.dateFormat = @"yyyy-MM-dd hh:mm:ss";//hh：12小时制，HH：24小时制
NSString *str = [dateformatter stringFromDate:date];
#从1970年1月1日至今所经历的秒数
NSTimeInterval seconds = [date timeIntervalSince1970];
#从指定时间到当前所经历的秒数
NSTimeInterval seconds = [date timeIntervalSinceNow];
#两个指定时间之间的秒数
NSTimeInterval seconds = [time1 timeIntervalSinceDate:time2];
#时间对比
NSDate *early = [time1 earlierDate:time2]; //较早
NSDate *later = [time1 laterDate:time2]; //较晚
[time1 isEqualToDate:time2] == YES //判断两个时间是否相同
#输入一个身份证号码判断年龄
scanf("%s", str);
NSString *ID = [NSString stringWithFormat:@"%s", str];
NSString *birthdayYear = [ID substringWithRange:NSMakeRange(6, 4)];
NSDate *date = [NSDate date];
NSDateFormatter *f = [[NSDateFormatter alloc] init];
f.dateFormat = @"yyyy";
NSString *thisYear = [f stringFromDate:date];
int age = [thisYear intValue] - [birthdayYear intValue];
NSLog(@"年龄是：%d", age);
2.0 NSArray
- NSArray *array3 = [NSArray arrayWithObjects:@"one", @"two", @"three", nil]; //创建数组包含多个元素
- NSArray *array4 = @[@"one", @"two", @"three"]; //优化方法，最常用的方法
- NSArray *array5 = [NSArray arrayWithArray:array4]; //副本
- NSUInteger index = [array4 indexOfObject:@"one"]; //根据元素值求在数组中的下标
- NSArray *stu = @[stu1, stu2, stu3];
NSArray *copied = [[NSArray alloc] initWithArray:stu copyItems:NO];//NO是引用计数拷贝
NSArray *deepCopied = [[NSArray alloc] initWithArray:stu copyItems:YES];//YES深拷贝2.1 NSMutableArray
- ###创建
- NSMutableArray *array1 = [NSMutableArray array];//空数组，有意义
- NSMutableArray *array2 = [NSMutableArray arrayWithCapacity:100];//预估值
- NSMutableArray *array3 = @[@"one", @"two", @"three"];//arra3会退化成不可变数组
- NSMutableArray *array4 = [NSMutableArray arrayWithObjects:@"one", @"two", @"three"];- ###添加
- [array4 addObject:@"four"];//在数组的最后添加一个元素
- [array4 insertObject:@"five" atIndex:1];//在任意下标插入- ###删除
- [array4 removeLastObject];//最后一个
- [array4 removeObject:@"six"];//指定元素
- [array4 removeObjectAtIndex:2];//指定下标
- [array4 removeObjectsInRange:NSMakeRange(3, 2)];//指定范围
- [array4 removeObjectsInArray:@[@"one", @"three"]];//指定数组
- [array4 removeAllObjects];//清空数组2.2 NSSet
int main(int argc, const char * argv[]) {
@autoreleasepool {
NSSet *set1 = [NSSet setWithObjects:@"one", @"two", @"three", nil];
//遍历
NSLog(@"%@", set1);
NSArray *array = [set1 allObjects];
for (int i = 0; i < array.count; i++)
{
NSLog(@"%@", array[i]);
}
for (NSString *str in set1)
{
NSLog(@"%@", str);
}
NSEnumerator *e = [set1 objectEnumerator];//枚举器遍历
NSSet *str;
while (str = [e nextObject])
{
NSLog(@"%@", str);
}
}
return 0;
}
2.3 NSMutableSet
int main(int argc, const char * argv[]) {
@autoreleasepool {
//创建
NSMutableSet *set1 = [NSMutableSet set];//空集合，有意义
NSMutableSet *set2 = [NSMutableSet setWithCapacity:100];//预估值
NSMutableSet *set3 = [NSMutableSet setWithObjects:@"one", @"two", @"three", nil];
//添加
[set3 addObject:@"four"];//一个
NSLog(@"%@", set3);
NSArray *added = @[@"five", @"six"];
[set3 addObjectsFromArray:added];//多个
NSLog(@"%@", set3);
//删除
[set3 removeObject:@"three"];//指定元素
NSLog(@"%@", set3);
[set3 removeAllObjects];//清空集合
NSLog(@"%lu", set3.count);
//交集
NSArray *added1 = @[@"one", @"two", @"three"];
[set3 addObjectsFromArray:added1];
NSArray *added2 = @[@"one", @"four", @"three"];
[set2 addObjectsFromArray:added2];
[set3 intersectSet:set2];//结果被放回set3
NSLog(@"%@", set3);
//并集
[set3 unionSet:set2];
NSLog(@"%@", set3);
//从一个集合A中删除另一个集合B中的元素
[set2 removeAllObjects];
[set2 addObjectsFromArray:added1];
[set3 removeAllObjects];
[set3 addObjectsFromArray:added2];
[set3 minusSet:set2];
NSLog(@"%@", set3);
}
return 0;
}2.4 NSDictionary
int main(int argc, const char * argv[]) {
@autoreleasepool {
//创建
NSDictionary *dict1 = [NSDictionary dictionaryWithObjectsAndKeys:@"one", @"1", @"two", @"2", @"three", @"3", nil];//标准
NSDictionary *dict2 = @{@"1":@"one", @"2":@"two", @"3":@"three"};//优化方法
NSArray *objects = @[@"one", @"two", @"three"];
NSArray *keys = @[@"1", @"2", @"3"];
NSDictionary *dict3 = [NSDictionary dictionaryWithObjects:objects forKeys:keys];//由数组
NSDictionary *dict4 = [NSDictionary dictionaryWithDictionary:dict3];//副本
//求键值对的个数
NSLog(@"%lu", dict4.count);
//获取字典中的所有值
NSArray *objects1 = [dict4 allValues];
//获取字典中的所有关键字
NSArray *keys1 = [dict4 allKeys];
//根据一个关键字来查找一个值
NSString *str = [dict4 objectForKey:@"1"];//标准
str = dict4[@"2"];//优化方法
//根据多个关键字来找多个值
NSArray *keys2 = @[@"1", @"4"];
NSArray *objects2 = [dict4 objectsForKeys:keys2 notFoundMarker:@"no object"];
//通过值找到对应的关键字
NSArray *keys3 = [dict4 allKeysForObject:@"three"];
//排序
TRStudent *stu1 = [[TRStudent alloc] initWithName:@"张三" andAge:18];
TRStudent *stu2 = [[TRStudent alloc] initWithName:@"李四" andAge:20];
TRStudent *stu3 = [[TRStudent alloc] initWithName:@"刘五" andAge:19];
NSDictionary *dict5 = @{@"1":stu1, @"2":stu2, @"3":stu3};
NSArray *sorted = [dict5 keysSortedByValueUsingSelector:@selector(compareAge:)];
for (NSArray *key in sorted)
{
NSLog(@"%@ - %@", key, dict5[key]);
}
NSArray *sortedName = [dict5 keysSortedByValueUsingSelector:@selector(compareName:)];
for (NSArray *key in sortedName)
{
NSLog(@"%@ - %@", key, dict5[key]);
}
//遍历
NSArray *keys4 = [dict5 allKeys];
for (NSString *key in keys4)
{
NSLog(@"%@-%@", key, dict5[key]);
}
NSEnumerator *e = [dict5 keyEnumerator];//关键字枚举器
NSString *key;
while (key = [e nextObject])
{
NSLog(@"%@-%@", key, dict5[key]);
}
NSEnumerator *e1 = [dict5 objectEnumerator];//值枚举器
TRStudent *stu;
while (stu = [e1 nextObject])
{
NSLog(@"%@", stu);
}
for (NSString *key in dict5)//OC循环
{
NSLog(@"%@-%@", key, dict5[key]);
}
//向文件中写
[dict2 writeToFile:@"/Users/tarena/Desktop/dict.plist" atomically:YES];
//从文件中读
NSDictionary *dict6 = [NSDictionary dictionaryWithContentsOfFile:@"/Users/tarena/Desktop/dict.plist"];
}
return 0;
}2.5 NSMutableDictionary
int main(int argc, const char * argv[]) {
@autoreleasepool {
//创建
NSMutableDictionary *dict1 = [NSMutableDictionary dictionary];//空字典，有意义
NSMutableDictionary *dict2 = [NSMutableDictionary dictionaryWithCapacity:100];//预估值
NSMutableDictionary *dict3 = [NSMutableDictionary dictionaryWithObjectsAndKeys:@"one", @"1", @"two", @"2", @"three", @"3", nil];//标准
NSMutableDictionary *dict4 = @{@"1":@"one", @"2":@"two", @"3":@"three"};//退化成不可变字典
//添加
[dict3 setValue:@"four" forKey:@"4"];//一个
NSLog(@"%@", dict3);
NSDictionary *added = @{@"5":@"five", @"6":@"six", @"7":@"seven"};
[dict3 addEntriesFromDictionary:added];//多个
NSLog(@"%@", dict3);
//覆盖
NSDictionary *dict5 = @{@"1":@"aaa", @"2":@"bbb", @"3":@"ccc"};
NSMutableDictionary *dict6 = [NSMutableDictionary dictionaryWithCapacity:100];
[dict6 addEntriesFromDictionary:dict5];
NSDictionary *dict7 = @{@"1":@"one", @"2":@"two", @"3":@"three"};
[dict6 setDictionary:dict7];
NSLog(@"%@", dict6);
//删除
[dict6 removeObjectForKey:@"1"];//指定关键字
NSLog(@"%@", dict6);
NSArray *keys = @[@"2", @"3"];
[dict6 removeObjectsForKeys:keys];//多个
NSLog(@"%@", dict6);
[dict6 removeAllObjects];//清空字典
NSLog(@"%lu", dict6.count);
}
return 0;
}
2.6 Block
int a = 10;
void (^myBlock)(void) = ^void(void){
NSLog(@"Block被执行了");
};
double (^myBlock1)(int, int) = ^double(int a, int b){
return b ? a * 1.0 / b : 0;
};
typedef void(^BlockType)(void);
typedef double(^BlockType1)(int, int);
int g_i = 10;
int main(int argc, const char * argv[]) {
@autoreleasepool {
myBlock();
NSLog(@"%g", myBlock1(2, 3));
BlockType b1;
b1 = ^void(void){
NSLog(@"用Block类型定义的变量");
};
b1();
BlockType1 b2 = ^double(int a, int b){
return b ? a * 1.0 / b : 0;
};
NSLog(@"%g", b2(2, 5));
//Block与全局变量
BlockType1 b3 = ^double(int a, int b){
NSLog(@"%d", g_i);//可以读取全局变量中的值
g_i = 20;
NSLog(@"%d", g_i);//可以对全局变量进行赋值
return g_i + a + b;
};
NSLog(@"%g", b3(2, 3));
//Block与局部变量
int i2 = 30;
__block int i3 = 50;
BlockType b4 = ^void(void){
NSLog(@"%d", i2);//可以读取局部变量中的值
//i2 = 40;//不可以对局部变量进行赋值
i3 = 60;//加block关键字后，可以对局部变量进行赋值
NSLog(@"%d", i3);
};
b4();
//与数组
NSNumber *a1 = [NSNumber numberWithInt:10];
NSNumber *a2 = [NSNumber numberWithInt:8];
NSNumber *a3 = [NSNumber numberWithInt:20];
NSNumber *a4 = [NSNumber numberWithInt:2];
NSNumber *a5 = [NSNumber numberWithInt:15];
NSArray *num = @[a1, a2, a3, a4, a5];
NSComparisonResult (^compareInt)(id, id) = ^NSComparisonResult(id obj1, id obj2){
NSNumber *a1 = obj1;
NSNumber *a2 = obj2;
int i1 = [a1 intValue];
int i2 = [a2 intValue];
if (i1 < i2)
{
return NSOrderedAscending;
}
else if (i1 > i2)
{
return NSOrderedDescending;
}
else
{
return NSOrderedSame;
}
};
NSArray *sorted = [num sortedArrayUsingComparator:compareInt];
NSLog(@"%@", sorted);
NSArray *strings = @[@"one", @"two", @"three"];
sorted = [strings sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2){
NSString *str1 = obj1;
NSString *str2 = obj2;
return [str1 compare:str2];
}];
NSLog(@"%@", sorted);
//与字典
NSDictionary *dict = @{@"1":@"one", @"2":@"two", @"3":@"three"};
sorted = [dict keysSortedByValueUsingComparator:^NSComparisonResult(id obj1, id obj2) {
NSString *str1 = obj1;
NSString *str2 = obj2;
return [str1 compare:str2];
}];
for (NSString *key in sorted)
{
NSLog(@"%@-%@", key, dict[key]);
}
TRMyClass *myC = [[TRMyClass alloc] init];
[myC method:^void(void){
NSLog(@"Block做函数参数");
}];
[myC method:^void(void){
NSLog(@"多态了");
}];
[myC getBlock]();
myC.block = ^void(void){
NSLog(@"Block作属性");
};
myC.block();
[myC method1:^double(int a, int b){
return a + b;
}];
[myC method1:^double(int a, int b){
return a * b;
}];
NSLog(@"%g", [myC getBlock1](2, 7));
myC.block1 = ^double(int a, int b)
{
return a + b;
};
NSLog(@"%g", myC.block1(2, 3));
myC.block1 = ^double(int a, int b)
{
return a * b;
};
NSLog(@"%g", myC.block1(2, 3));
}
return 0;
}@implementation TRMyClass
-(void)method
{
NSLog(@"method被执行了");
}
-(void)method:(MyBlock2)b
{
b();//回调
}
-(MyBlock2)getBlock
{
MyBlock2 b = ^void(void){
NSLog(@"Block作函数返回值");
};
return b;
}
-(void)method1:(MyBlock3)b
{
NSLog(@"%g", b(2, 3));
}
-(MyBlock3)getBlock1
{
return ^double(int a, int b){
return a * 1.0 / b;
};
}
@end
2.7 KVC
TRDept *dept2 = [[TRDept alloc]init];
NSMutableDictionary *deptdata = [NSMutableDictionary dictionary];
deptdata[@"name"] = @"test2";
deptdata[@"emps"] = @[ed, ee, ef,ed,ee,ef];
// KVC
[dept2 setValuesForKeysWithDictionary:deptdata];2.8 NSBundle
- 从文件获取内容到数组
NSString *fullpath = [[NSBundle mainBundle] pathForResource:@"dept_emps.plist" ofType:nil];
NSArray *dataArray = [NSArray arrayWithContentsOfFile:fullpath];
NSLog(@"%@",dataArray);
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