文件路徑相關的方法在NSPathUtilities中,主要是操作路徑

獲得一個路徑

 NSString *documents = [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) objectAtIndex:0]; //獲得Document的路徑
//---~~~/Application/43A22272-F08C-4078-93A9-CAF451BF9814/Documents  //~~~是省略寫法



NSArray *components = [documents pathComponents]; //路徑的每個節點的元素
     
     "/",
     Users,
     admin,
     Library,
     Developer,
     CoreSimulator,
     Devices,
     "87AB942E-1A11-479C-8010-1F5C36646658",
     data,
     Containers,
     Data,
     Application,
     "43A22272-F08C-4078-93A9-CAF451BF9814",
     Documents


NSString *lastPathComponent = [documents lastPathComponent]; //最後的一個路徑節點元素
    //---Documents

NSString *stringByDeletingLastPathComponent = [documents stringByDeletingLastPathComponent];//刪除最後一個路徑節點元素
    //---~~~/Application/3B14DAE5-8890-42E1-8DC1-664BB35B6333
NSString *stringByAppendingPathComponent = [documents stringByAppendingPathComponent:@"new.txt"]; //添加一個路徑元素
    //---~~~/Application/20FED3FC-859A-4C56-945A-FFEEB17A93A2/Documents/new.txt
NSString *pathExtension = [stringByAppendingPathComponent pathExtension];  //文件的後綴名
    //---txt
NSString *stringByDeletingPathExtension = [stringByAppendingPathComponent stringByDeletingPathExtension]; //去掉後綴名
    //---~~~/Application/20FED3FC-859A-4C56-945A-FFEEB17A93A2/Documents/new
NSString *stringByAppendingPathExtension = [stringByDeletingPathExtension stringByAppendingPathExtension:@"txt"]; //添加後綴名
    //---~~~/Application/20FED3FC-859A-4C56-945A-FFEEB17A93A2/Documents/new.txt
NSString *stringByAbbreviatingWithTildeInPath = [documents stringByAbbreviatingWithTildeInPath];  //變成相對路徑,前面的都用波浪號省略
    //--- ~/Documents
NSString *stringByExpandingTildeInPath = [stringByAbbreviatingWithTildeInPath stringByExpandingTildeInPath]; //把相對路徑變成絕對路徑
NSArray *stringsByAppendingPaths = [documents stringsByAppendingPaths:@[@"a",@"b",@"c.txt"]];  //批量添加多個路徑,得到一個路徑數組
    //---~~~/Application/16474B22-B287-4F7C-9931-E7454B83822E/Documents/a
    //---~~~/Application/16474B22-B287-4F7C-9931-E7454B83822E/Documents/b
    //---~~~/Application/16474B22-B287-4F7C-9931-E7454B83822E/Documents/c.txt