Make a txt file in internal storage in android

问题

i want to make one folder on root and put txt file and append data '

My java code

  public void generateNoteOnSD(String sFileName, String sBody){
        try
        {
            String fileName = "error";
            String headings = "Hello, world!";
            String path = "/data/root/";
            File file = new File(path, fileName+".txt");
            if (!file.exists()) {
                file.mkdirs();
            }
            File gpxfile = new File(file, sFileName);
            FileWriter writer = new FileWriter(gpxfile);
            writer.append(sBody);
            writer.flush();
            writer.close();
           // Toast.makeText(this, "Saved", Toast.LENGTH_SHORT).show();
        }
        catch(IOException e)
        {
            Log.d("file error", ""+e.getMessage());
        }
       }  

I am getting file not found exception

Please help me how can create a file on root folder in internal storage

回答1:

Try this function.

public void wrtieFileOnInternalStorage(Context mcoContext,String sFileName, String sBody){
    File file = new File(mcoContext.getFilesDir(),"mydir");
    if(!file.exists()){
        file.mkdir();
    }

    try{
        File gpxfile = new File(file, sFileName);
        FileWriter writer = new FileWriter(gpxfile);
        writer.append(sBody);
        writer.flush();
        writer.close();

    }catch (Exception e){

    }
}

回答2:

Try something like this -

public Boolean writeToSD(String text){
        Boolean write_successful = false;
         File root=null;  
            try {  
                // <span id="IL_AD8" class="IL_AD">check for</span> SDcard   
                root = Environment.getExternalStorageDirectory();  
                Log.i(TAG,"path.." +root.getAbsolutePath());  

                //check sdcard permission  
                if (root.canWrite()){  
                    File fileDir = new File(root.getAbsolutePath());  
                    fileDir.mkdirs();  

                    File file= new File(fileDir, "samplefile.txt");  
                    FileWriter filewriter = new FileWriter(file);  
                    BufferedWriter out = new BufferedWriter(filewriter);  
                    out.write(text);  
                    out.close();  
                    write_successful = true;
                }  
            } catch (IOException e) {  
                Log.e("ERROR:---", "Could not write file to SDCard" + e.getMessage());  
                write_successful = false;
            }  
        return write_successful;
    }

From here - http://www.coderzheaven.com/2012/09/06/read-write-files-sdcard-application-sandbox-android-complete-example/

回答3:

In this statement:

File gpxfile = new File(file, sFileName);

file should be directory (you use .txt file here).

Also, read this. You can store you file in /data/data/<your.package.name>/ dir (trying to use /data/root/ will cause Permission denied error).

回答4:

Try this. Using this, I have created log file in SD card.

public void writeFile(String text){

    File tarjeta = Environment.getExternalStorageDirectory();
    File logFile = new File(tarjeta.getAbsolutePath()+"/", "log.txt");
    if (!logFile.exists())
    {
        try
        {
            logFile.createNewFile();
        } 
        catch (IOException e)
        {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }
    try
    {
        //BufferedWriter for performance, true to set append to file flag
        BufferedWriter buf = new BufferedWriter(new FileWriter(logFile, true)); 
        buf.append(text);
        buf.newLine();
        buf.close();
    }
    catch (IOException e)
    {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
}

来源：https://stackoverflow.com/questions/24751703/make-a-txt-file-in-internal-storage-in-android