数组(可变与不可变)和字典(可变与不可变)中元素对象的类型,必须是NSString,NSArray,NSDictionary,NSData,否则不能直接写入文件
#pragma mark---NSString的写入与读取---
//1:获取路径
NSString *docunments = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)firstObject];
//2:在该路径下创建文件夹,文件夹名为字符串.txt
docunments = [docunments stringByAppendingString:@"/字符串.txt"];
// NSLog(@"%@",docunments);
//3:编写文本内容
NSString *str = @"大家一起来";
//4:将文本写入到"字符串.txt"中
/*
writeToFile:文件路径,在这里是documents atomically:YES(若为YES,则保证了文件的原子性,即先创建一个临时文件,直到文件内容写入成功再导入目标文件(字符串.txt),为NO,直接写入目标文件里) encoding:编码格式是个枚举值 error:错误信息,一般为nil
*/
BOOL result = [str writeToFile:docunments atomically:YES encoding:NSUTF8StringEncoding error:nil];
if (result) {
NSLog(@"我成功了");
}else{
NSLog(@"为啥失败了");
}
//读取
/*
stringWithContentsOfFile:路径 encoding:编码 error:nil,错误信息
*/
NSString *newStr = [NSString stringWithContentsOfFile:docunments encoding:4 error:nil];
NSLog(@">>>>%@",newStr);
/*
.plist全名是：Property List，属性列表文件，它是一种用来存储串行化(当程序彻底退出后,对象就会随之消亡,但是,我们希望有些东西需要记录下来,以便于恢复,也可提升用户体验,而记录的这个过程,就叫串行化)后的对象的文件。属性列表文件的扩展名为.plist ，因此通常被称为 plist文件。文件是xml格式的。
注意:plist文件通常用于存储用户设置,也可用于存储捆绑信息
*/
#pragma mark---NSArray的写入与读取
//获取路径
NSString *arrayDoc = [SandBox getDocuments];
//在arrayDoc下拼接文件名
NSString *arrPath = [arrayDoc stringByAppendingString:@"array.plist"];
//向数组中写入数据
NSArray *array = @[@"25",@"55",@"05",@"5885"];
//将数组写入文件
[array writeToFile:arrPath atomically:YES];
NSLog(@"数组存入路径%@",arrPath);
//读取
NSArray *newArray = [NSArray arrayWithContentsOfFile:arrPath];
NSLog(@"读取的文件:%@",newArray);
#pragma mark--- 字典的写入与读取----
NSString *dicionaryDic = [SandBox getDocuments];
NSString *dicpath = [dicionaryDic stringByAppendingString:@"dictionary.plist"];
NSDictionary *dictionary = @{@"name":@"甲甲",@"age":@"18"};
[dictionary writeToFile:dicpath atomically:YES];
NSLog(@"字典存入路径%@",dicpath);
//读取
NSDictionary *newdict = [NSDictionary dictionaryWithContentsOfFile:dicpath];
NSLog( @"读取的字典文件%@",newdict);
#pragma mark--- NSData----
NSString *DataPath = [[SandBox getDocuments]stringByAppendingString:@"Data.data"];
// NSString *string = @"丑八怪";
// NSData *data = [string dataUsingEncoding:NSUTF8StringEncoding];
UIImage *image = [UIImage imageNamed:@"2"];
NSData *data = UIImageJPEGRepresentation(image, 0.5);
[data writeToFile:DataPath atomically:YES];
NSLog(@"%@",DataPath);
//读取
NSData *newData = [NSData dataWithContentsOfFile:DataPath];
// NSString *new = [[NSString alloc]initWithData:newData encoding:4];
UIImage *new = [UIImage imageWithData:newData scale:1];
NSLog(@"%@",newData);
NSLog(@"%@",new);
}
