ios 文件操作 检查文件是否存在 创建文件目录 iphone

- (NSString *)dataPath:(NSString *)file

{

NSString *path = [[NSHomeDirectory() stringByAppendingPathComponent:@"Documents"] stringByAppendingPathComponent:@"badge"];

BOOL bo = [[NSFileManager defaultManager] createDirectoryAtPath:path withIntermediateDirectories:YES attributes:nil error:nil];

NSAssert(bo,@"创建目录失败");

NSString *result = [path stringByAppendingPathComponent:file];

return result;

}

- (void)viewDidLoad

{

[super viewDidLoad];

//此处首先指定了图片存取路径（默认写到应用程序沙盒 中）

NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory,NSUserDomainMask, YES);

//并给文件起个文件名

NSString *imageDir = [[[paths objectAtIndex:0] stringByAppendingPathComponent:@"163"] stringByAppendingPathComponent:@"songzi"];

//存放图片的文件夹

NSString *imagePath =[imageDir stringByAppendingPathComponent:@"文件名.png"];

NSData *data = nil;

//检查图片是否已经保存到本地

if([self isExistsFile:imagePath]){

data=[NSData dataWithContentsOfFile:imagePath];

}else{

data = [NSData dataWithContentsOfURL:[NSURL URLWithString: @"网址"]];

//创建文件夹路径

[[NSFileManager defaultManager] createDirectoryAtPath:imageDir withIntermediateDirectories:YES attributes:nil error:nil];

//创建图片

[UIImagePNGRepresentation([UIImage imageWithData:data]) writeToFile:imagePath atomically:YES];

}

imageView.image = [UIImage imageWithData:data];

}

检查文件是否存在

NSString *path = [[NSBundle mainBundle] pathForResource:fileName ofType:@""];

if(path==NULL)