ctri+I Xcode 格式化
//文件夹操作
1.输出文件中固定路径的代码行数
NSString *content=[NSString stringWithContentsOfFile:@”/Users/chenkq/Desktop/未命名文件夹/1-porcoto/1-porcoto/main.m” encoding:NSUTF8StringEncoding error:nil];
2.拆分字符串(类似。net 中的)split(‘,’)
NSArray *array=[content componentsSeparatedByString:@”\n”];
3.遍历集合 类似 foreacrch
for(NSString *line in array)
{
NSLog(@”%@”,line);
}
4.文件操作类 单例
NSFileManager *msFile=[NSFileManager defaultManager];
5.判断文件是否存在
BOOL dir=NO;
//&作为将值类型作为引用类型传入内存地址,类似java 的 ref(才会直接改变dir 的值)
BOOL exist=[msFile fileExistsAtPath:path isDirectory:&dir];
6.文件类型过滤类
NSString *extenstring=[path pathExtension];
if(![extenstring isEqualToString:@”h”] && ![extenstring isEqualToString:@”m”] && ![extenstring isEqualToString:@”c”])
7.拼接字符串方法 stringWithFormat
NSString *filepath=[NSString stringWithFormat:@”%@/%@”,path,fileName];
8.找到某个字符串对象的位置
NSRange range=[path rangeOfString:@”1212”];
9.把某个字符串的位置替换为另外的字符串
NSString *str=[path stringByReplacingCharactersInRange:range withString:@”“];
10.可变素组,对应Array
NSMutableArray *array=[NSMutableArray arrayWithObjects:@”1”,@”2”,@”3”,nil];
NSArray *arry=@[@”1”,@”q”] 只创建不可变素组可用
- 集合
1.相同点 NSSet NSArray 都是集合都能存放多个OC对象
只能存放OC对象, 不能存在非OC 对象
都有一个可变的子类
不同点
NSSet 无序 NSArray 有序
NSMutableSet *dset=[NSMutableSet set]; 可变集合
NSArray 集合
- 字典集合
NSMutableDictionary 可变 无序
NSDictionary *dict=@{@”name”:@”chekq”,@”address”:@”北京”};
id obj=dict[@”name”];
不可变的数组不可以传给可变数组
.字典中的值不可重复
NSMutableDictionary *nsDict=[NSMutableDictionary dictionary];
[nsDict setObject:@”1” forKeyedSubscript:@”123”]
NSArray *persons=@[
@{@"nname":@"javk",@"qq":@"1217276730"},
@{@"nname2":@"javk1",@"qq":@"12172767301"},
@{@"nname3":@"javk2",@"qq":@"12172767302"},
@{@"nnam4":@"javk3",@"qq":@"12172767303"}
];
/*
NSArray /NSMutableArray
有序
快速创建(不可变):@[]
快速访问:素组名[i]
NSSet /NSMutableSet
无序
NSDictionary/ NSMutableDictionary
无序
快速创建:{key:value,key:value}
快速访问: 字典名[key]
@20 将包装成一个NSNumber 对象
因为NSNumber 之所以包装基础数据类型,
是因为继承了NSValue
1.OBJECT 语法加强
//封源的,看不到源代码
Foundation 框架(苹果提供)
NSObject 所有类的基类 NSString
NSlog(“%@”,)
//拼接字符串
[NSString stringWithFormat:@”%@,%@”,@”1”,@”2”]
1>如何获取字符串
NSString *str=@”12345”;
NSUInteger length=[str Length];
NSLog(@”字符串长度 %lu”,length)
2>根据索引获得单个字符串
NSString *str2=@”www.itcast.cn”;
如果你给定的字符串长度,会导致异常 Range or index out of founds
unichar c=[str2 characterAtIndex:5];
NSLog(@”获得字符 %c”,c);
3>根据索引获得一个子字符串
NSString str3=@”www.itcast.cn”;
//subsringFromIndex 给定的索引开始 (包含该索引位置的开始)
//substringToIndex 截取字符串到给定的索引位置介绍(不包含该索引位置)
NSString *tempStr=[str3 substringFromIndex:3]; //.itcast.cn
NSString *tempStr=[str3 substringFromIndex:3];//www
4>根据字符串获得该字符串在另一个字符串的索引的位置
5>根据字符串获得字符串的范围
6>截取字符串的某一段
NSRange rang={1,2};
/【起始索引位置 包含该索引 】location 索引的位子 length 要截取的长度
NSString *tempStr3=[str3 substringWithRange: rang];
7//获得一个字符串的索引位置
NSString *tempStr=@”itcast”;
NSString *str4=@”www.itcast.cn”;
NSRange tempRange=[str3 rangeOfString:str4];
NSLog(@”location=%d,length=%d”, tempRange.location, tempRange.length);
//NSStringFromRange可以吧结构体转换成字符串
NSLog(@”%@”,NSStringFromRange(tempRange))
if(tempRange.location==NSNotFound)//没有找到
8:获得一个字符串所有范围
字符串的判断
1.判断字符串是否为null
基本数据类型转换成字符串
int 转换成字符串
int a=0;
NSString *str1=[NSString stringWithFormat:@”%d”,a];
float f=2.4;
NSString *str2=[NSString stringWithFormat:@”%.lf”,f];
double d=78.123
NSString str3=[NSString stringWithFormat:@”%.4f”,d]
char c=’c’;
NSString str4=[NSString stringWithFormat:@”%c”,c];
NSString *str6=@”1”;
int i1=[str6 intValue];
NSString *str7=@”2.3”;
float fl=[str7 floatValue];
NSLog(@”fl %.lf”,f1);
NSString *str8=@”8.88”;
double d1=[str8 doubleValue];
NSLog(@”d1 %.2f”,d1);
NSString *str9=@”i268”;
int i2=[str9 intValue];
NSString *str10=@”china”;
NSString *temp1=[str10 uppercaseString];//转换成大写
-字符串重组
//1.多个数据拼接成一个字符串
int year = 1988;
int month = 4;
int day = 15;
NSString * date = [NSString stringWithFormat:@”%d年%d月%d日”,year,month,day];
NSLog(@”date %@”,date);
NSString * address = @”昌平区,金燕龙”;
NSString * dateAndAddrss = [NSString stringWithFormat:@”%@地址:%@”,date,address];
NSLog(@”dateAndAddress %@”,dateAndAddrss);
//2.字符串的末尾追加新的字符
NSString * str1 = @"www.";
NSString * str2 = [str1 stringByAppendingString:@"itcast.cn"];
NSLog(@"str2 %@ str1 %@",str2,str1);
//3.在制定的范围追加字符串
NSString * str3 = @"www.cn";
NSRange range = {4,0};
// 4 location代表的时从哪个索引开始插入,length 代表的意思可以覆盖几个字符
NSString * str4 = [str3 stringByReplacingCharactersInRange:range withString:@"itcast."];
NSLog(@"str4 %@",str4);
//4.使用新的字符,替换原有的字符
NSString * str5 = @"www.itcast.cn";
NSString * str6 = [str5 stringByReplacingOccurrencesOfString:@"w" withString:@"a"];
NSLog(@"str6 %@",str6);
//5.在字符串中删除特定的某些字符 胡汉三 hhs
NSString * str7 = @"www---.itcatst.--cn";
NSString * str8 = [str7 stringByReplacingOccurrencesOfString:@"-" withString:@""];
NSLog(@"str8 %@",str8);
//6.去掉字符串中的空格
NSString * str9 = @"www .itcat .cn";
NSString * str10 = [str9 stringByReplacingOccurrencesOfString:@" " withString:@""];
NSLog(@"str10 %@",str10);
//将字符串写入到文件
NSString * content = @”浙江冰雹,如汤圆大小,习近平万岁”;
NSString * path = @”/Users/aplle/Desktop/共享课堂/mytest.txt”;
//1.参数1 要给入文件目录(并且要包括文件名称)
//2.atomically : YES
//3.NSUTF8StringEncoding 国际通用的编码格式
//4.NSError 是用来记录错误信息的
NSError * error;
BOOL isWriteSuccess = [content writeToFile:path atomically:YES encoding:NSUTF8StringEncoding error:&error];
if(isWriteSuccess)
{
NSLog(@"文件创建成功");
}
else
{
NSLog(@"error %@",error);
}
//要给出文件路径
//你写入文件的时候,使用的是什么编码格式,读取的时候就要给我用什么编码格式
NSString * path = @”/Users/aplle/Desktop/共享课堂/mytest.txt”;
NSError * error;
NSString * str = [NSString stringWithContentsOfFile:path encoding:NSUTF8StringEncoding error:&error];
if (error != nil) {
NSLog(@"error message %@",error);
}
else {
NSLog(@"str content %@",str);
}
/*
NSString * str = @”abc”;
NSString * str2 = [str stringByAppendingString:@”bbc”];
NSLog(@"str2 %@ str %@",str2,str);
str = @"abcbbc";
*/
//1.创建可变字符串
//NSMutableString 继承自 NSString
//NSMutableString 用油NSString所有的属性以及方法
// NSMutableString * muStr = [[NSMutableString alloc] init];
NSMutableString * muStr = [[NSMutableString alloc] initWithCapacity:0];
//是初始化字符串内容
[muStr setString:@”www”];
NSLog(@”mustr %p”,muStr);
//动态的给字符串末尾追加新值
[muStr appendString:@”.cn”];
//在指定的索引位置,插入字符串
[muStr insertString:@".itcast" atIndex:3];
//删除指定范围的字符串
//你要删除的长度,一定不能够超出字符串的的长度,导致异常Range or index out of bounds
NSRange range = {3,7};
// [muStr deleteCharactersInRange:range];
[muStr replaceCharactersInRange:range withString:@”传智播客”];
NSLog(@”muStr %@”,muStr);
//1.创建一个NSRange结构体 表示范围
NSRange range = {4,5};
NSRange range2 = NSMakeRange(4, 5);
NSString * strRange = NSStringFromRange(range);
NSLog(@”strRange %@”,strRange);
//2.NSSize 等同于 CGSize 有两个值组成 weight表示宽度 height高度
NSSize size = {21,19};
NSSize size2 = NSMakeSize(21, 19);
NSString *strSize = NSStringFromSize(size2);
NSLog(@"strSize %@",strSize);
//3.NSPoint 等同CGPoint 表示一个点的坐标位置
NSPoint point = {20,40};
NSPoint point2 = NSMakePoint(20, 40);
NSString * strPoint = NSStringFromPoint(point);
NSLog(@”strPoint %@”,strPoint);
//4.NSRect
NSRect rect = {40,60,100,200};
NSRect rect2 = NSMakeRect(0, 10, 100, 100);
NSString * strRect = NSStringFromRect(rect);
NSLog(@”strRect %@”,strRect);
/集合中,不能存储基本数据类型,如果你想要把基本数据类型存储到数组,集合中,就必须把它转换成基本数据类型的包装类
@autoreleasepool {
//int float double char
int a = 10;
// [NSString stringWithFormat:@”%d”,a];
//1.使用NSNumber 包装 int数据类型
NSNumber * number1 = [NSNumber numberWithInt:a];
NSLog(@"%@",number1);
//2.直接转换成字符串
NSString * strInt = [number1 stringValue];
NSLog(@"strInt %@",strInt);
//3.float包装成NSNumber
NSNumber * number2 = [NSNumber numberWithFloat:98.98];
NSLog(@"number2 %@",[number2 stringValue]);
//4.包装类转换成基本数据类型
int b = [number1 intValue];
NSLog(@"%d",b);
//1.创建集合
//NSArray 是不可变数组,一旦创建完成就不能够对数组进行,添加,删除等操作
NSArray * array = [[NSArray alloc] init];
NSLog(@"%@",array);
//2.通过构造方法的方式创建一个NSArray
//在创建一个NSArray的时候,集合的最后一个元素一定是nil
NSArray * array1 = [NSArray arrayWithObjects:@"one",@"two",@"three", nil];
NSLog(@"%@",array1);
//3.数组中可以存储不同类型的对象
NSNumber * number = [NSNumber numberWithInt:10];
NSArray * array2 = [[NSArray alloc] initWithObjects:@"one",@"two",number, nil];
NSLog(@"array2 %@",array2);
//4.数组实际上存储的时对象的地址,同样也可以存储数组的地址
NSArray * a1 = [[NSArray alloc] initWithObjects:@"one",@"two",@"three", nil];
NSArray * a2 = [[NSArray alloc] initWithObjects:@"1",@"2",@"3", nil];
NSArray * a3 = [[NSArray alloc] initWithObjects:a1,a2, nil];
NSLog(@"a3 %@",a3);
//5.存储自定义的对象
//最好都给我重写 description方法
Person * p1 = [[Person alloc] initWithName:@"xiaozhe" andAge:20];
Person * p2 = [[Person alloc] initWithName:@"hell" andAge:18];
Person * p3 = [[Person alloc] initWithName:@"marray" andAge:38];
NSArray * array3 = [[NSArray alloc] initWithObjects:p1,p2,p3, nil];
NSLog(@"array3 %@",array3);
//6.数组中存储基本数据类型,
//如果你要在数组中存储基本数据类型,请给我包装好了之后在去存 NSNumber
//注意不要把nil值存储到NSArray中,会导致数据丢失
NSString * str = nil;
NSArray * array4 = [[NSArray alloc] initWithObjects:@"2",str,[NSNumber numberWithInt:23], nil];
NSLog(@"array4 %@",array4);
//7.创建数组的快捷方式
NSArray * karray = @[@"a",@"b",@"c"];
NSLog(@"karray %@",karray);
//8.快速获得一个数组中的元素
NSString * kstr = karray[0];
NSLog(@"kstr %@",kstr);
}
pragma mark 从集合中取出对象
{
//9.从集合中取出数据
NSArray * array = [[NSArray alloc] initWithObjects:@"one",@"two",@"three", nil];
//数组的index时从0开始的
NSString * str = [array objectAtIndex:0];
NSLog(@"str %@",str);
//10.获得数组的元素个数
NSUInteger arrayCount = [array count];
NSLog(@"arrayCount %d",arrayCount);
}
pragma mark 判断数组中是否存在某个对象
{
Person * p1 = [[Person alloc] initWithName:@"xiaozhe" andAge:20];
Person * p2 = [[Person alloc] initWithName:@"nihao" andAge:30];
NSArray * array = @[p1,p2];
BOOL isContain = [array containsObject:p1];
if (isContain)
{ NSLog(@"存在");
}else { NSLog(@"不存在");
}
}
//1.使用for循环遍历数组
NSArray * array = @[@”one”,@”two”,@”three”];
for (int i = 0; i < array.count; i++) {
NSString * str = array[i];
NSLog(@”array[%d] = %@”,i,str);
}
//1.数据类型
//BOOL id NSObject * (NSString * NSArray *) block SEL
//2.流程控制语句
// 增强for循环
/*
for (NSObject * obj in array)
{
}
*/
//你的array.count值是多少,他就会循环多少次,每一次都取出数据中的一个元素
//存储到str中
//2.使用增强for循环的方式遍历数组
for (NSString * str in array) {
NSLog(@"str = %@",str);
}
//3.注意事项
//如果你的数组中村粗了多种不同类型的数据,那么最好不要调用某个对象特有的方法,会导致程序崩溃
//在实际的开发中,一个数组往往只负责存储一种数据类型
Person * p1 = [[Person alloc] init];
NSArray * array2 = @[@"one",[NSNumber numberWithInt:10],p1];
for (NSString * str in array2) {
// NSLog(@”array2 str %@”,str);
// NSLog(@”str %ld”,str.length);
}
//3.枚举器
NSArray * array3 = @[@"one",@"two",@"three"];
NSEnumerator * enumerateor = [array3 objectEnumerator];
NSString * value;
while (value = [enumerateor nextObject]) {
NSLog(@"enum str %@",value);
}
//1.使用sortedArrayUsingSelector
//也是最简单的排序方式
//数组是按照你存入元素的顺序存储的
NSArray * array = @[@”b”,@”d”,@”a”,@”z”];
NSLog(@”排序前 array %@”,array);
array = [array sortedArrayUsingSelector:@selector(compare:)];
// NSArray * array1 = [array sortedArrayUsingSelector:@selector(compare:)];
NSLog(@”排序后 array %@”,array);
//2.使用block方式排序
NSArray * array2 = @[@"z",@"4",@"b",@"3",@"x"];
NSLog(@"array2 排序前 %@",array2);
array2 = [array2 sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
/*
NSComparisonResult retuslt = [obj1 compare:obj2];
return retuslt;
*/
//obj1 compare obj2 就是正序排序
// return [obj1 compare:obj2];
//obj2 compare obj1 就是倒序排序
return [obj2 compare:obj1];
}];
NSLog(@”array2 排序后 %@”,array2);
Person * p1 = [[Person alloc] initWithName:@"xiaozhe" andAge:20 andYear:@"1990"];
Person * p2 = [[Person alloc] initWithName:@"alex" andAge:18 andYear:@"2990"];
Person * p3 = [[Person alloc] initWithName:@"merry" andAge:25 andYear:@"1890"];
NSArray * array3 = @[p1,p2,p3];
NSLog(@"array3 排序前 %@",array3);
//3.使用 给数组排序
//如果你向给你自己定义的对象排序,必须根据某一个属性来排序,
//sortDescriptorWithKey 参数要的就是你对象中,要依据哪个属性来排序,你就把哪个属性的名字当成key传入
//ascending YES表示正序 NO表示倒叙
NSSortDescriptor * d1 = [NSSortDescriptor sortDescriptorWithKey:@"age" ascending:NO];
NSSortDescriptor * d2 = [NSSortDescriptor sortDescriptorWithKey:@"year" ascending:NO];
//如果你要使用多个属性进行排序,默认在前面的NSSortDescriptor优先级比较高
NSArray * descripts = @[d2,d1];
array3 = [array3 sortedArrayUsingDescriptors:descripts];
NSLog(@"array 3 排序后 %@",array3);
//4.
NSArray * array4 = @[p1,p2,p3];
NSLog(@"array4 排序前 %@",array4);
array4 = [array4 sortedArrayUsingComparator:^NSComparisonResult(id obj1, id obj2) {
Person * p1 = obj1;
Person * p2 = obj2;
return [p1.year compare:p2.year];
}];
NSLog(@"array4 排序后 %@",array4);
}
// 可变数组
//NSMutableArray 继承至 NSArray
// NSArray * array = @[];
//1.创建可变数组
NSMutableArray * array = [[NSMutableArray alloc] initWithCapacity:0];
//使用addObject 动态给数组中增加元素
/*
[array addObject:@"one"];
[array addObject:@"two"];
[array addObject:@"three"];
[array addObject:@"one"];
*/
NSString * str1 = @"one";
NSString * str2 = @"two";
NSString * str3 = @"three";
//数组中可以存储,同一个对象多次
[array addObject:str1];
[array addObject:str2];
[array addObject:str3];
[array addObject:str1];
//2.指定对象插入的位置
[array insertObject:str1 atIndex:2];
//3.删除 会通过对象,删除数组中所有的同一个地址的对象
[array removeObject:str1];
//4.通过索引的方式删除对象,超出了数组的count值,那么就会导致异常 index beyond bounds
[array removeObjectAtIndex:0];
[array addObject:str2];
[array addObject:str3];
[array addObject:str1];
//5.删除数组中所有的元素
[array removeAllObjects];
NSLog(@"array %@",array);
[array addObject:str2];
[array addObject:str3];
[array addObject:str1];
//1.for换遍历
for (int i = 0; i < array.count; i++){
NSString * str = [array objectAtIndex:i];
//在遍历数组的时候,千万不要给数组中,增加,或者删除元素
// [array removeObject:str1];
NSLog(@”str %@”,str);
}
//2.增强for循环
for (NSString * str in array) {
// [array removeObject:str1];
//如果你在增强for循环中,删除元素,会直接导致异常出现
NSLog(@”str %@”,str);
}
//3.枚举器
NSEnumerator * enumerator = [array objectEnumerator];
NSString * value;
while (value = [enumerator nextObject]) {
//如果你在枚举器中,删除元素,会直接导致异常出现
// [array removeObject:str1];
NSLog(@”str %@”,value);
}
//4.要通过遍历的方式确定删除哪个元素怎么办
NSMutableArray * array2 = [[NSMutableArray alloc] init];
[array2 addObject:@"1"];
[array2 addObject:@"2"];
[array2 addObject:@"3"];
[array2 addObject:@"4"];
[array2 addObject:@"5"];
NSMutableArray * tmp = [[NSMutableArray alloc] init];
for (NSString * str in array2) {
if ([str isEqualToString:@"3"]) {
[tmp addObject:str];
}
}
NSLog(@"array2 %@",array2);
NSLog(@"tmp %@",tmp);
//遍历临时数组
for (int i = 0; i < tmp.count; i++) {
NSString * str = [tmp objectAtIndex:i];
//从原数组中删除,临时数组中存储的对象
[array2 removeObject:str];
}
————不可变字典
//1.创建字段,不可变的
NSDictionary * dic = [NSDictionary dictionaryWithObjectsAndKeys:@”xiaozhe”,@”name”, nil];
NSLog(@”dic %@”,dic);
//2.快捷创建方式
NSDictionary * dic2 = @{ @"one":@"1",@"two":@"2"};
NSLog(@"dic2 %@",dic2);
//3.字典中可以存任意数据类型
// 字典的顺序不是自然顺序
NSArray * array = @[@"one",@"two"];
NSDictionary * dic3 = @{
@"one":@"1",
@"num":[NSNumber numberWithInt:10],
@"aaa":dic2,
@"bbb":dic,
@"ar1":array };
NSLog(@"dic3 %@",dic3);
//4.获得字典的长度
NSLog(@"count %ld",dic3.count);
//5.从字典中取值
NSString * str = [dic3 objectForKey:@"one"];
NSLog(@"str %@",str);
NSDictionary * dicTmp = [dic3 objectForKey:@"aaa"];
NSLog(@"dicTmp %@",dicTmp);
NSArray * arrayTmp = [dic3 objectForKey:@"ar1"];
NSLog(@"arrayTmp %@",arrayTmp);
//6.遍历
//取出所有的key值
NSArray * allkeys = [dic3 allKeys];
NSLog(@"allkeys %@",allkeys);
for (int i = 0; i < allkeys.count; i++) {
NSString * key = [allkeys objectAtIndex:i];
//如果你的字典中存储的多种不同的类型,那么最好用id类型去接受它
id obj = [dic3 objectForKey:key];
NSLog(@"obj %@",obj);
}
//2.枚举器
NSEnumerator * enumerator = [dic3 objectEnumerator];
id value;
while (value = [enumerator nextObject]) {
NSLog(@"value %@",value);
}
–可变字典
//1.创建一个可变长度字典
NSMutableDictionary * muDic = [[NSMutableDictionary alloc] initWithCapacity:0];
//2.向字典中村如数据
[muDic setObject:@”1” forKey:@”one”];
[muDic setObject:@”2” forKey:@”two”];
[muDic setObject:@”3” forKey:@”three”];
NSLog(@”muDic %@”,muDic);
//3.删除
[muDic removeObjectForKey:@"one"];
NSLog(@"muDic %@",muDic);
//4.全部删除
[muDic removeAllObjects];
NSLog(@"muDic %@",muDic);
Student * stu1 = [[Student alloc] initWithName:@"xiaoher" andAge:20];
Student * stu2 = [[Student alloc] initWithName:@"alex" andAge:50];
Student * stu3 = [[Student alloc] initWithName:@"xiaoli" andAge:10];
[muDic setObject:stu1 forKey:@"s1"];
[muDic setObject:stu2 forKey:@"s2"];
[muDic setObject:stu3 forKey:@"s3"];
//在向字典中存储数据的时候,一定要保证key值是唯一的
// [muDic setObject:stu3 forKey:@”s3”];
// [muDic setObject:stu3 forKey:@”s3”];
// [muDic setObject:stu3 forKey:@”s3”];
NSLog(@”muDic %@”,muDic);
//1.使用for循环遍历字典
NSArray * allkeys = [muDic allKeys];
for (int i = 0; i < allkeys.count; i++) {
NSString * key = [allkeys objectAtIndex:i];
Student * stu = [muDic objectForKey:key];
NSLog(@"stu %@",stu);
};
//2.使用枚举器
NSEnumerator * enumerator = [muDic objectEnumerator];
Student * tmp;
while (tmp = [enumerator nextObject]) {
NSLog(@"tmp %@",tmp);
}
—NSSet
/NSArray 自然顺序
//NSSet是无序的
//注意:这个是最为重要的功能 NSSet中不能够存储重复的数据,可以用它来去除重复的值
NSString * str1 = @”one”;
NSString * str2 = @”two”;
NSString * str3 = @”three”;
NSSet * set = [[NSSet alloc] initWithObjects:str1,str2,str3,str1, nil];
NSLog(@”set %@”,set);
NSLog(@"count %ld",set.count);
BOOL isContains = [set containsObject:str1];
if (isContains){
NSLog(@"YES");
}
else {
NSLog(@"NO");
}
//4.遍历
NSEnumerator * enumerator = [set objectEnumerator];
NSString * value;
while (value = [enumerator nextObject]) {
NSLog(@"value %@",value);
}
//1 创建一个可变集合—-可变集合
NSMutableSet * muSet = [[NSMutableSet alloc] init];
//2.增加值
[muSet addObject:str1];
[muSet addObject:str2];
NSLog(@”muSet %@”,muSet);
//3.删除
[muSet removeObject:str1];
NSLog(@”muSet %@”,muSet);
//4.删除所有
// [muSet removeAllObjects];
NSLog(@"muSet %@",muSet);
//5.遍历
NSEnumerator * en = [muSet objectEnumerator];
NSString * value;
while (value = [en nextObject]) {
NSLog(@"value %@",value);
}
//1.NSArray 转换成 NSMutableArray
NSArray * array = @[@”one”,@”two”,@”three”];
NSMutableArray * muArray = [NSMutableArray arrayWithArray:array];
NSLog(@”muarray %@”,muArray);
//2.NSDictonary 转换成 NSMutableDictionary
NSDictionary * dic = @{@"one":@"1",@"two":@"2"};
NSMutableDictionary * muDic = [NSMutableDictionary dictionaryWithDictionary:dic];
NSLog(@"mudic %@ ",muDic);
//3.NSset 转换成 NSMutableSet
NSSet * set = [[NSSet alloc] initWithObjects:@"one",@"two", nil];
NSMutableSet *muSet = [NSMutableSet setWithSet:set];
NSLog(@"muSet %@",muSet);
//4.NSArray 转换成NSSet
NSMutableSet * muSet2 = [NSMutableSet setWithArray:array];
NSLog(@"muSet2 %@",muSet2);
//5.NSDictionary 转化成NSArray
NSArray * allkeys = [dic allKeys];
NSLog(@"allkeys %@",allkeys);
NSArray * allValues = [dic allValues];
NSLog(@"allValues %@",allValues);
//6.字符串转换成数组
NSString * str = @"www.itacast.cn";
NSArray * strArray = [str componentsSeparatedByString:@"."];
NSLog(@"strArray %@",strArray);
—集合内存管理
// retainCount 1
Person * p = [[Person alloc] init];
//1
NSMutableArray * array = [[NSMutableArray alloc] initWithCapacity:0];
//当你把对象存入到,数组中的时候,数组会对这个对象进行一次 retain操作
[array addObject:p];// [p retain] retaiCount 2
//当你把一个对象移除数组中的时候,会对该对象进行一次 release操作 retainCount 1
// [array removeObject:p];
//会对数组中所有的对象,进行一次,relsease操作
// [array removeAllObjects];
//当集合对象被销毁的时候,会对其内部所有的对象进行一次 release操作
//0
[array release];
//retainCount - 0
//0
[p release];
13-ARC机制集合内存管理
//ARC机制,是否需要担心内存溢出呢
//谁告诉你不用的心得啊:道理就是下面的示
Person * p = [[Person alloc] init];
NSMutableArray * array = [[NSMutableArray alloc] init];
//当一个对象被存入集合中的时候,默认会保存它的强指针
[array addObject:p];
//当个把一个对象从集合中,删除的时候,会释放掉这个对象的强指针
// [array removeObject:p];
// [array removeAllObjects];
array = nil;
p = nil;
NSLog(@”adfasdf”);
//1.文件管理器
NSFileManager * f1 = [NSFileManager defaultManager];
NSLog(@”%p”,f1);
NSFileManager * f2 = [NSFileManager defaultManager];
NSLog(@"%p",f2);
NSFileManager * f3 = [[NSFileManager alloc] init];
NSLog(@"f3 %p",f3);
NSFileManager * f4 = [NSFileManager defaultManager];
NSLog(@"%p",f4);
//在整个程序没有退出之前,只需要创建一次,我们就可以把它写成单利模式
//简单的单例模式
User * u1 = [User defaultUser];
u1.age = 10;
NSLog(@"u1 %p",u1);
User * u2 = [User defaultUser];
NSLog(@"u2 %p age = %d",u2,u2.age);
User * u3 = [[User alloc] init];
NSLog(@"u3 %p",u3);
//1.组合模式,(聚合模式)
//2.单利模式
//3.策略模式(封装变化点),block
//4.向上抽象 (protocol(协议))
//5.享元设计模式(NSString池原理)
//静态变量,整个程序运行完成的时候才会被释放掉,mian函数运行完成
static User * instance = nil;
+ (User *)defaultUser {
// return [[self alloc] init];
if (instance == nil) {
instance = [[self alloc] init];
}
return instance;
}
NSString * str = @"www.itcast.cn";
NSError * error;
BOOL isWriteSuccess = [str writeToFile:@"/Users/aplle/Desktop/test.txt" atomically:YES encoding:NSUTF8StringEncoding error:&error];
if (isWriteSuccess) {
NSLog(@"创建成功");
} else {
NSLog(@"error %@",error);
}
*/
//1.获取文件管理器
NSFileManager * fileManager = [NSFileManager defaultManager];
NSString * path = @"/Users/aplle/Desktop/test.txt";
NSError * error;
NSDictionary * dic = [fileManager attributesOfItemAtPath:path error:&error];
NSLog(@"dic %@",dic);
if (error == nil) {
NSDate * date = [dic objectForKey:NSFileCreationDate];
NSString * size = [dic objectForKey:NSFileSize];
NSLog(@" date = %@, size = %@",date,size);
}
}
获取目录文件以及目录列表
/*
//1.
NSFileManager * fileManager = [NSFileManager defaultManager];
NSString * path = @”/Users/aplle/Desktop/装机”;
NSError * error;
//只能够火的目标目录下,第一级目录
NSArray * array = [fileManager contentsOfDirectoryAtPath:path error:&error];
NSLog(@"array %@",array);
*/
NSFileManager * fileManager = [NSFileManager defaultManager];
NSString * path = @"/Users/aplle/Desktop/other";
NSError * error;
//能够逐级的获得所有子集的目录
NSArray * array = [fileManager subpathsOfDirectoryAtPath:path error:&error];
NSLog(@"array %@",array);
目录管理
//1 创建目录
NSFileManager * fileManager = [NSFileManager defaultManager];
NSString * path = @”/Users/aplle/Desktop/myfolder/aaa”;
NSError * error;
//withIntermediateDirectories YES 逐级创建文件夹,NO表示只能够创建一级目录
BOOL isCreateSuccess = [fileManager createDirectoryAtPath:path withIntermediateDirectories:YES attributes:nil error:&error];
if (isCreateSuccess) {
NSLog(@"创建成功");
} else {
NSLog(@"error %@",error);
}
*/
//2 移动目录 移动就是剪切操作
/*
NSFileManager * fileManager = [NSFileManager defaultManager];
NSString * path = @"/Users/aplle/Desktop/myfolder";
NSString * pathTo = @"/Users/aplle/Desktop/newmyfolder";
NSError * error ;
BOOL isMoveSuccess = [fileManager moveItemAtPath:path toPath:pathTo error:&error];
if (isMoveSuccess) {
NSLog(@"移动成功");
}
else {
NSLog(@"error %@",error);
}
*/
//3.删除
/*
NSFileManager * fileManager = [NSFileManager defaultManager];
NSString * path = @"/Users/aplle/Desktop/newmyfolder";
NSError * error;
BOOL isRemoveSuccess = [fileManager removeItemAtPath:path error:&error];
if (isRemoveSuccess) {
NSLog(@"删除成功");
}
else {
NSLog(@"erro %@",error);
}
*/
//4.拷贝文件
NSFileManager * fileManager = [NSFileManager defaultManager];
NSString * path = @"/Users/aplle/Desktop/myfolder";
NSString * pathTo = @"/Users/aplle/Desktop/newmyfolder";
NSError * error;
BOOL isCopySuccess = [fileManager copyItemAtPath:path toPath:pathTo error:&error];
if(isCopySuccess) {
NSLog(@"拷贝成功");
}
else {
NSLog(@"error %@",error);
}
14-管理文件 NSData
//1.获得文件
//mp3.mp4 rmvb mkv pdf doc txt
/*
NSString * path = @”/Users/aplle/Desktop/屏幕快照 .png”;
NSData * data = [NSData dataWithContentsOfFile:path];
NSLog(@”%ld”,data.length);
NSFileManager * fileManager = [NSFileManager defaultManager];
NSString * pathTo = @"/Users/aplle/Desktop/屏幕快照副本.png";
BOOL isCreateSuccess = [fileManager createFileAtPath:pathTo contents:data attributes:nil];
if (isCreateSuccess) {
NSLog(@"创建成功");
}
else {
NSLog(@"创建失败");
}
*/
/*
//2.移动文件 相当于剪切操作
NSFileManager * fileManager = [NSFileManager defaultManager];
NSString * path = @"/Users/aplle/Desktop/屏幕快照 .png";
NSString * pathTo = @"/Users/aplle/Desktop/newmyfolder/屏幕屏幕.png";
NSError * error;
BOOL ismoveSuccess = [fileManager moveItemAtPath:path toPath:pathTo error:&error];
if (ismoveSuccess) {
NSLog(@"移动成功");
}
else {
NSLog(@"error %@",error);
}
*/
NSFileManager * fileManager = [NSFileManager defaultManager];
NSString * path = @"/Users/aplle/Desktop/屏幕快照副本.png";
NSError * error;
BOOL isremove = [fileManager removeItemAtPath:path error:&error];
if (isremove) {
NSLog(@"删除成功");
}
else {
NSLog(@"error %@",error);
}
NSData数据类
//音频文件,文本文件,视频文件就必须使用NSData数据类
/*
NSString * str = @”www.itcast.cn”;
NSError * error;
[str writeToFile:@”/Users/aplle/Desktop/text.txt” atomically:YES encoding:NSUTF8StringEncoding error:&error];
*/
/*
NSString * path = @”/Users/aplle/Desktop/text.txt”;
//把目标文件加载到内存中.
//NSData 是不可变长度的Data类型,只能够通过一次加载完成所有的数据
NSData * data = [NSData dataWithContentsOfFile:path];
NSLog(@"data length %ld",data.length);
NSString * pathTo = @"/Users/aplle/Desktop/nextext.txt";
//把加载到内存中的文件,写入到指定的位置
BOOL isWriteSuccess = [data writeToFile:pathTo atomically:YES];
if (isWriteSuccess) {
NSLog(@"写入成功");
}
else {
NSLog(@"写入失败");
}
*/
//当需要把多个NSData数据拼接成一个数据存储的时候,就要想到使用NSMutableData这个类型
NSString * str1 = @"好好学习";
NSString * str2 = @"天天向上";
NSString * str3 = @"今天休息";
NSMutableData * muData = [[NSMutableData alloc] init];
NSData * d1 = [str1 dataUsingEncoding:NSUTF8StringEncoding];
NSData * d2 = [str2 dataUsingEncoding:NSUTF8StringEncoding];
NSData * d3 = [str3 dataUsingEncoding:NSUTF8StringEncoding];
//appendData 能够把nsdata对象加入到 muData对象中
[muData appendData:d1];
[muData appendData:d2];
[muData appendData:d3];
NSString * path = @"/Users/aplle/Desktop/传智播客校训.txt";
//NSMutableData是继承至NSData的所以可以调用writeToFile 把数据写入到一个指定的目录下
BOOL iswriteSucess = [muData writeToFile:path atomically:YES];
if (iswriteSucess) {
NSLog(@"创建成功");
}
else {
NSLog(@"创建失败");
}
/*格式化日期操作
NSDate * date = [NSDate date];
//表示格式化日期对象
NSDateFormatter * f = [[NSDateFormatter alloc] init];
[f setDateFormat:@"yyyy-MM-dd hh:mm:ss"];//2014/03/21
//把格式与我们的日期关联起来
NSString * str = [f stringFromDate:date];
NSLog(@"str %@",str);
*/
//把字符串转换成日期
/*
NSString * str = @"2014/03/20";
NSDateFormatter * f = [[NSDateFormatter alloc] init];
[f setDateFormat:@"yyyy/MM/dd"];
NSDate * date = [f dateFromString:str];
NSLog(@"date %@",date);
*/
//处理时区问题
NSDate * newDate = [NSDate date];
NSDateFormatter * f = [[NSDateFormatter alloc] init];
[f setDateFormat:@"yyyy-MM-dd HH:mm:ss"];
NSString * str = [f stringFromDate:newDate];
//设置时差计算方法 //GTM
[f setTimeZone:[NSTimeZone timeZoneWithAbbreviation:@"UTC"]];
NSLog(@"%@",str);
//获得日期对象
NSDate * date = [NSDate date];
NSLog(@"date %@",date);