iPhone 文件读写操作
1,写文件操作
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- (IBAction)btnWrite:(id)sender { //创建文件管理器 NSFileManager *fileManager = [NSFileManager defaultManager]; //获取路径 //参数 要获取的哪种路径 NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentDirectory = [paths objectAtIndex:0]; //去除需要的路径 //更改到操作的目录下 [fileManager changeCurrentDirectoryPath:[documentDirectory stringByExpandingTildeInPath]]; //创建文件fileName文件名称,contents文件内容,如果开始没有内容可以设置为nil,attributes文件的属性,初始为nil [fileManager createFileAtPath:@ "fileName" contents:nil attributes:nil]; //删除待删除文件 [fileManager removeItemAtPath:@ "createNewFile" error:nil]; //获取文件路径 NSString *path = [documentDirectory stringByAppendingPathComponent:@ "fileName" ]; NSLog(@ "path == %@" ,path); //待写入的数据 NSString *temp = @ "Hello world" ; int data0 = 1000000; float data2 = 23.23f; //创建数据缓冲 NSMutableData *writer = [[NSMutableData alloc]init]; //将字符串添加到缓冲中 [writer appendData:[temp dataUsingEncoding:NSUTF8StringEncoding]]; [writer appendBytes:&data0 length: sizeof (data0)]; [writer appendBytes:&data2 length: sizeof (data2)]; [writer writeToFile:path atomically:YES]; [writer release]; } |
2,读文件操作
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- (IBAction)btnRead:(id)sender { //创建文件管理器 NSFileManager *fileManager = [NSFileManager defaultManager]; //获取路径 //参数 要获取的哪种路径 NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentDirectory = [paths objectAtIndex:0]; //去除需要的路径 //更改到操作的目录下 [fileManager changeCurrentDirectoryPath:[documentDirectory stringByExpandingTildeInPath]]; //创建文件fileName文件名称,contents文件内容,如果开始没有内容可以设置为nil,attributes文件的属性,初始为nil [fileManager createFileAtPath:@ "fileName" contents:nil attributes:nil]; //删除待删除文件 [fileManager removeItemAtPath:@ "createNewFile" error:nil]; //获取文件路径 NSString *path = [documentDirectory stringByAppendingPathComponent:@ "fileName" ]; NSLog(@ "path == %@" ,path); //待写入的数据 NSString *temp = @ "Hello world" ; int data0 = 1000000; float data2 = 23.23f; //创建数据缓冲 NSMutableData *writer = [[NSMutableData alloc]init]; //将字符串添加到缓冲中 [writer appendData:[temp dataUsingEncoding:NSUTF8StringEncoding]]; [writer appendBytes:&data0 length: sizeof (data0)]; [writer appendBytes:&data2 length: sizeof (data2)]; [writer writeToFile:path atomically:YES]; [writer release]; //读取操作 int gData0; float gData1; NSString *gData2; NSData *reader = [NSData dataWithContentsOfFile:path]; gData2 = [[NSString alloc]initWithData:[reader subdataWithRange:NSMakeRange(0, [temp length])] encoding:NSUTF8StringEncoding]; [reader getBytes:&gData0 range:NSMakeRange([temp length], sizeof (gData0))]; [reader getBytes:&gData1 range:NSMakeRange([temp length]+ sizeof (gData0) , sizeof (gData1))]; NSLog(@ "gData0 == %d" ,gData0); NSLog(@ "gData1 == %f" ,gData1); NSLog(@ "gData2 == %@" ,gData2); // lblText.text = gData2; } |
iphone实现文件的读写操作
iphone可以很容易的实现文件的读写,但是如果你没有使用苹果公司99美元开发者sdk的话,你利用破解打出来的api包,安装到手机上不能把文件写入手机.下面是我实现读写的代码:
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#import "ManagerFile.h" @implementation ManagerFile -( void )writeFile:(NSString *)file { //创建文件管理器 NSFileManager *fileManager = [NSFileManager defaultManager]; //获取路径 //参数NSDocumentDirectory要获取那种路径 NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDirectory = [paths objectAtIndex:0]; //去处需要的路径 //更改到待操作的目录下 [fileManager changeCurrentDirectoryPath:[documentsDirectory stringByExpandingTildeInPath]]; //创建文件fileName文件名称,contents文件的内容,如果开始没有内容可以设置为nil,attributes文件的属性,初始为nil //获取文件路径 [fileManager removeItemAtPath:@ "username" error:nil]; NSString *path = [documentsDirectory stringByAppendingPathComponent:@ "username" ]; //创建数据缓冲 NSMutableData *writer = [[NSMutableData alloc] init]; //将字符串添加到缓冲中 [writer appendData:[file dataUsingEncoding:NSUTF8StringEncoding]]; //将其他数据添加到缓冲中 //将缓冲的数据写入到文件中 [writer writeToFile:path atomically:YES]; [writer release]; } -(NSString *)readFile { //创建文件管理器 NSFileManager *fileManager = [NSFileManager defaultManager]; //获取路径 //参数NSDocumentDirectory要获取那种路径 NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES); NSString *documentsDirectory = [paths objectAtIndex:0]; //去处需要的路径 //更改到待操作的目录下 [fileManager changeCurrentDirectoryPath:[documentsDirectory stringByExpandingTildeInPath]]; //获取文件路径 NSString *path = [documentsDirectory stringByAppendingPathComponent:@ "username" ]; NSData *reader = [NSData dataWithContentsOfFile:path]; return [[NSString alloc] initWithData:reader encoding:NSUTF8StringEncoding]; } @end |
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原文链接:http://www.cnblogs.com/cpcpc/archive/2012/07/17/2595186.html