一、在Documents、tmp和Library中存储文件
Documents：用于存储应用程序中经常需要读取或写入的常规文件。
tmp：用于存储应用程序运行时生成的文件。（随着应用程序的关闭失去了利用价值）
Library：一般存放应用程序的配置文件，比如说plist类型的文件。
二、读取和写入文件
1、新建Empty Application应用程序，添加HomeViewController文件。
HomeViewController.h代码：
| 1 | #import <UIKit/UIKit.h> |
| 2 | |
| 3 | @interface HomeViewController : UIViewController |
| 4 | { |
| 5 | |
| 6 | } |
| 7 | - (NSString *) documentsPath;//负责获取Documents文件夹的位置 |
| 8 | - (NSString *) readFromFile:(NSString *)filepath; //读取文件内容 |
| 9 | - (void) writeToFile:(NSString *)text withFileName:(NSString *)filePath;//将内容写到指定的文件 |
| 10 | @end |
HomeViewController.m代码：
| 1 | #import "HomeViewController.h" |
| 2 | @interface HomeViewController () |
| 3 | @end |
| 4 | @implementation HomeViewController |
| 5 | //负责获取Documents文件夹的位置 |
| 6 | - (NSString *) documentsPath{ |
| 7 | NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); |
| 8 | NSString *documentsdir = [paths objectAtIndex:0]; |
| 9 | return documentsdir; |
| 10 | } |
| 11 | |
| 12 | |
| 13 | //读取文件内容 |
| 14 | - (NSString *) readFromFile:(NSString *)filepath{ |
| 15 | if ([[NSFileManager defaultManager] fileExistsAtPath:filepath]){ |
| 16 | NSArray *content = [[NSArray alloc] initWithContentsOfFile:filepath]; |
| 17 | NSString *data = [[NSString alloc] initWithFormat:@"%@", [content objectAtIndex:0]]; |
| 18 | [content release]; |
| 19 | return data; |
| 20 | } else { |
| 21 | return nil; |
| 22 | } |
| 23 | } |
| 24 | //将内容写到指定的文件 |
| 25 | - (void) writeToFile:(NSString *)text withFileName:(NSString *)filePath{ |
| 26 | NSMutableArray *array = [[NSMutableArray alloc] init]; |
| 27 | [array addObject:text]; |
| 28 | [array writeToFile:filePath atomically:YES]; |
| 29 | [array release]; |
| 30 | } |
| 31 | |
| 32 | |
| 33 | -(NSString *)tempPath{ |
| 34 | return NSTemporaryDirectory(); |
| 35 | } |
| 36 | - (void)viewDidLoad |
| 37 | { |
| 38 | NSString *fileName = [[self documentsPath] stringByAppendingPathComponent:@"content.txt"]; |
| 39 | |
| 40 | //NSString *fileName = [[self tempPath] stringByAppendingPathComponent:@"content.txt"]; |
| 41 | |
| 42 | [self writeToFile:@"苹果的魅力！" withFileName:fileName]; |
| 43 | |
| 44 | NSString *fileContent = [self readFromFile:fileName]; |
| 45 | |
| 46 | NSLog(fileContent); |
| 47 | |
| 48 | [super viewDidLoad]; |
| 49 | } |
| 50 | @end |
效果图：
本文转载至 http://mobile.9sssd.com/ios/art/953