public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); File sdCard = Environment.getExternalStorageDirectory(); //取得sdCard 的目录 try { //测试创建文件和文件夹 boolean CreateFileResult = createFile(sdCard.getAbsolutePath(),"sdCreateFile.sq",false); //创建文件 boolean CreateDirResult = createFile(sdCard.getAbsolutePath(),"sdCreateDir.dir",true); //创建文件夹 } catch (IOException e) {e.printStackTrace();} //测试删除文件和文件夹 boolean deleteFileResult = deleteFile(sdCard.getAbsolutePath(), "sdCreateFile.sq"); boolean deleteDirResult = deleteFile(sdCard.getAbsolutePath(), "sdCreateDir.dir"); } //创建文件夹或目录 boolean createFile(String path,String fileName,boolean isDir) throws IOException { File dir = new File(path); if(dir.exists()!=true) return false; //path no exists File newFile = new File(path+"/"+fileName); return isDir==true? newFile.mkdir():newFile.createNewFile(); } //删除文件夹或目录 boolean deleteFile(String path,String fileName) { File dir = new File(path); if(dir.exists()!=true)return false; //path no exists return new File(path+"/"+fileName).delete(); }