flutter创建文件文件夹

static Future<String> saveVoiceDirectory(String url) async {
 requestPermission();
 final filepath = await getApplicationDocumentsDirectory();
 var file = Directory(filepath.path + "/" + url);
 try {
   bool exists = await file.exists();
   if (!exists) {
     await file.create();
     print("创建成功");
   } else {
     print("已存在");
   }
 } catch (e) {
   print(e);
 }
 return file.path.toString();
}

创建文件

saveVoiceDirectory("flutter").then((value) {
   File file = new File(
       value + "/" + "${DateTime.now().millisecondsSinceEpoch}.pcm");
   if (!file.existsSync()) {
     file.createSync();
   }
 });  

文件权限

 static Future requestPermission() async {
 if (await Permission.contacts.request().isGranted) {
   // Either the permission was already granted before or the user just granted it.
 }
   // You can request multiple permissions at once.
 Map<Permission, PermissionStatus> statuses = await [
   Permission.storage,
 ].request();
 print(statuses[Permission.storage]);
}