文件操作1

//iOS沙盒中一共有4个文件夹：Documents/tmp/app/Library

---安装目录（home），只读

   ---Documents：长期放用户文件或文件夹，rw

   ---A.app：mainBundle,存放可执行文件和资源文件，r

   ---tmp：存放临时文件，rw

   ---Library

      ---Caches：存放缓存文件，rw

- (NSString *)stringByAppendingPathComponent:(NSString *)str;

stringByAppendingPathComponent：字符串附加路径要素

NSArray *NSSearchPathForDirectoriesInDomains(NSSearchPathDirectory directory, NSSearchPathDomainMask domainMask, BOOL );
NSSearchPathForDirectoriesInDomains：在域名里寻找目录的路径

- (BOOL)writeToFile:(NSString *)path atomically:(BOOL)useAuxiliaryFile encoding:(NSStringEncoding)enc error:(NSError **)error;
useAuxiliaryFile：用附加的文件  NSUTF8StringEncoding：中文编码

    

NSString *home = NSHomeDirectory();    NSLog(@"%@",home);  //获取安装目录home的路径        NSString *documents = [home stringByAppendingPathComponent:@"Documents"];    NSLog(@"XXX%@",documents);  //添加Documents，获取Documents目录的路径    //stringByAppendingPathComponent：字符串附加路径要素        NSArray *array = NSSearchPathForDirectoriesInDomains(NSCachesDirectory, NSUserDomainMask, YES);    //NSSearchPathForDirectoriesInDomains：在域名里寻找目录的路径，NSUserDomainMask：用户安装目录；把Caches的目录的地址存入数组    NSLog(@"---%@",array);//    NSString *doc2 = [array objectAtIndex:0];    NSString *doc2 = [array firstObject];  //将数组首元素赋给doc2    NSLog(@"+++%@",doc2);        NSString *tmp = NSTemporaryDirectory();    NSLog(@"%@",tmp);   //获取Temporary目录的路径        NSString *name = @"戴维营";    NSString *path = [documents stringByAppendingPathComponent:@"test1.plist"]; //在documents目录下添加文件test1.plist    [name writeToFile:path atomically:YES encoding:NSUTF8StringEncoding error:nil]; //将name写入文件，NSUTF8StringEncoding：中文编码    NSLog(@"%@",path);        //获取当前程序中的资源文件路径    NSString *dbPath = [[NSBundle mainBundle] pathForResource:@"testDB" ofType:@"db"];    NSLog(@"%@",dbPath);