Using the file system

Using file system in Haxe is made easy because of the sys package. These are the Haxe targets that can directly access the filesystem:

Name	Access to filesystem
C++	Yes
C#	Yes
PHP	Yes
Java	Yes
Python	Yes
Lua	Yes
Macro	Yes
HL (HashLink)	Yes
Neko	Yes
JavaScript	No
NodeJS (using hxnodejs)	Yes
ActionScript 3	No
Flash	No

Note that in macros you can access file system.

Check if FileSystem is available

You can safely access the sys-package if you wrap the code with conditional compilation:

#if sys
trace("file system can be accessed");
#end

Otherwise you will get the error: "You cannot access the sys package while targeting js (for sys.FileSystem)".

Read content of a file

This example reads a text file:

var content:String = sys.io.File.getContent('my_folder/my_file.txt');
trace(content);

Save file to disk

This example writes an object person to a json file:

var user = {name:"Mark", age:31};
var content:String = haxe.Json.stringify(user);
sys.io.File.saveContent('my_folder/my_file.json',content);

Api documentation: https://api.haxe.org/sys/io/File.html

Cross platform paths

Dealing with paths, directories, slashes, extensions on multiple platforms or OSes can be slightly awkward. Haxe provides the haxe.io.Path class which supports the common path formats.

Extracting info from a path:

var location = "path/to/file.txt";
var path = new haxe.io.Path(location);
trace(path.dir); // path/to
trace(path.file); // file
trace(path.ext); // txt

Combining info into a new path:

var directory = "path/to/";
var file = "./file.txt";
trace(haxe.io.Path.join([directory, file])); // path/to/file.txt

Api documentation: https://api.haxe.org/haxe/io/Path.html

Recursive loop through all directories / files

function recursiveLoop(directory:String = "path/to/") {
  if (sys.FileSystem.exists(directory)) {
    trace("directory found: " + directory);
    for (file in sys.FileSystem.readDirectory(directory)) {
      var path = haxe.io.Path.join([directory, file]);
      if (!sys.FileSystem.isDirectory(path)) {
        trace("file found: " + path);
        // do something with file
      } else {
        var directory = haxe.io.Path.addTrailingSlash(path);
        trace("directory found: " + directory);
        recursiveLoop(directory);
      }
    }
  } else {
    trace('"$directory" does not exists');
  }
}

Api documentation: https://api.haxe.org/sys/FileSystem.html

Checking file attributes

var stat:sys.FileStat = sys.FileSystem.stat("myFile.txt");
trace("Last access time: " + stat.atime);
trace("Last modification time: " + stat.mtime);
trace("Last status change time: " + stat.ctime);
trace("The user id: " + stat.uid);
trace("File size: " + stat.size);

Api documentation: https://api.haxe.org/sys/FileStat.html