[iOS基础]文件读取详解

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文件操作

创建文件夹： NSString *imageDir = [NSString stringWithFormat:@"%@/Caches/%@", NSHomeDirectory(), dirName]; BOOL isDir = NO; NSFileManager *fileManager = [NSFileManager defaultManager]; BOOL existed = [fileManager fileExistsAtPath:imageDir isDirectory:&isDir]; if ( !(isDir == YES && existed == YES) ) {  [fileManager createDirectoryAtPath:imageDir withIntermediateDirectories:YES attributes:nil error:nil]; }删除文件夹及文件级内的文件： NSString *imageDir = [NSString stringWithFormat:@"%@/Caches/%@", NSHomeDirectory(), dirName]; NSFileManager *fileManager = [NSFileManager defaultManager]; [fileManager removeItemAtPath:imageDir error:nil];

文件读写解析

http://blog.csdn.net/diqun1314/article/details/7245501
http://3lian.com/edu/2013/10-14/101565.html

读取txt文件

 NSString *tmp;        NSArray *lines; /*将文件转化为一行一行的*/        lines = [[NSString    stringWithContentsOfFile:@"testFileReadLines.txt"]                       componentsSeparatedByString:@"\n"];         NSEnumerator *nse = [lines objectEnumerator];         // 读取<>里的内容         while(tmp = [nse nextObject]) {                  NSString *stringBetweenBrackets = nil;                  NSScanner *scanner = [NSScanner scannerWithString:tmp];                  [scanner scanUpToString:@"<" intoString:nil];                  [scanner scanString:@"<" intoString:nil];                  [scanner scanUpToString:@">" intoString:&stringBetweenBrackets];                  NSLog([stringBetweenBrackets description]);          }

文件读取的四种方法

//第一种方法： NSFileManager实例方法读取数据        NSArray* paths = NSSearchPathForDirectoriesInDomains(NSDesktopDirectory, NSUserDomainMask, YES);        NSString* thepath = [paths lastObject];        thepath = [thepath stringByAppendingPathComponent:@"fd_list.txt"];        NSLog(@"桌面目录：%@", thepath);        NSFileManager* fm = [NSFileManager defaultManager];        NSData* data = [[NSData alloc] init];        data = [fm contentsAtPath:thepath];        NSLog(@"%@",[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]);        //第二种方法： NSData类方法读取数据        data = [NSData dataWithContentsOfFile:thepath];        NSLog(@"NSData类方法读取的内容是：%@",[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]);        //第三种方法： NSString类方法读取内容        NSString* content = [NSString stringWithContentsOfFile:thepath encoding:NSUTF8StringEncoding error:nil];        NSLog(@"NSString类方法读取的内容是：\n%@",content);        //第四种方法： NSFileHandle实例方法读取内容        NSFileHandle* fh = [NSFileHandle fileHandleForReadingAtPath:thepath];        data = [fh readDataToEndOfFile];        NSLog(@"NSFileHandle实例读取的内容是：\n%@", [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding]);

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