简单数据的读写操作
iOS中提供了对一下四种(包括他们的子类)可直接进行文件存取的操作
- NSString(字符串)
- NSArray(数组)
- NSdictionary(字典)
- NSData(数据)
获取Document文件目录下的文件路径
- (NSString *)GetThefilePath:(NSString *)filePath{ NSString *Path = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)firstObject]stringByAppendingPathComponent:filePath]; return Path;}复制代码
字符串的存取
存储一个字符串
- 获取要存储的文件路径
NSString *filePath = [self GetThefilePath:@"name.plist"];复制代码
- 将一个字符串写入到一个文件中
NSString *name = @"蓝欧科技";[name writeToFile: filePath atomically:YES encoding:NSUTF8StringEncoding error:NULL];复制代码
- 将一个字符串归档到一个文件中
NSString *name = @"蓝欧科技";[NSKeyedArchiver archiveRootObject:name toFile:[self GetThefilePath:@"name1.plist"]];复制代码
取出一个字符串
- 简单的读取
NSString *string = [NSString stringWithContentsOfFile:[self GetThefilePath:@"name.plist"] encoding:NSUTF8StringEncoding error:NULL];复制代码
- 反归档一个字符串
NSString *string = [NSKeyedUnarchiver unarchiveObjectWithFile:[self GetThefilePath:@"name1.plist"]];复制代码
数组的存取
存储一个数组
- 将一个数组写入到文件中
//创建一个数组NSArray *array = @[@"小李",@"小红",@"Mark"];[array writeToFile:[self GetThefilePath:@"array.txt"] atomically:YES];复制代码
- 将一个数组归档到一个文件中
NSArray *array = @[@"小李",@"小红",@"Mark"];[NSKeyedArchiver archiveRootObject:array toFile:[self GetThefilePath:@"array.txt"]];复制代码
###读取一个数组
- 简单的读取
NSArray *array_1 = [NSArray arrayWithContentsOfFile:[self GetThefilePath:@"array.txt"]];复制代码
- 反归档一个数组
NSArray *array_2 = [NSKeyedUnarchiver unarchiveObjectWithFile:[self GetThefilePath:@"array.txt"]];复制代码
字典的存取
字典的存储
- 简单的写入
//创建一个字典NSDictionary *dictionary = @{@"name":@"小红",@"age":@22,@"sex":@"男"};[dictionary writeToFile:[self GetThefilePath:@"dictionary.txt"] atomically:YES];复制代码
- 将字典归档到文件中
//创建一个字典NSDictionary *dictionary = @{@"name":@"小红",@"age":@22,@"sex":@"男"};[NSKeyedArchiver archiveRootObject:dictionary toFile:[self GetThefilePath:@"dictionary.txt"]];复制代码
字典的读取
- 简单的读取
NSDictionary *dictionary_1 = [NSDictionary dictionaryWithContentsOfFile:[self GetThefilePath:@"dictionary.txt"]];复制代码
- 返归档一个字典
NSDictionary *dictionary_2 = [NSKeyedUnarchiver unarchiveObjectWithFile:[self GetThefilePath:@"dictionary.txt"]];复制代码
NSData的存取
NSData的存储
- 先将一个图片转换为NSData格式,然后在进行存储
NSData *imageData = UIImagePNGRepresentation([UIImage imageNamed:@"4.png"]);复制代码
- 将NSData数据写入到文件中
[imageData writeToFile:[self GetThefilePath:@"image.txt"] atomically:YES];复制代码
- 将NSData数据进行归档
[NSKeyedArchiver archiveRootObject:imageData toFile:[self GetThefilePath:@"image.txt"]];复制代码
NSData的读取
- 从文件读取出来的还是一个NSData类型的数据
NSData *imageData_1 = [NSData dataWithContentsOfFile:[self GetThefilePath:@"image.txt"]];复制代码
- 反归档一个NSData
NSData *imageData_1 = [NSKeyedUnarchiver unarchiveObjectWithFile:[self GetThefilePath:@"image.txt"]];复制代码