xamarin Android : can not create a file in storage-CodePudding

I have been searching for two days continuously on this problem, but I did not get any answer, I want to create a file on the storage in Android and put data in it. but always there is an error on it . error: Access to path "/storage/emulated/0/esi2.txt" is denied.

list of permissions:

<manifest xmlns:android="http://schemas.android.com/apk/res/android" android:versionCode="1" android:versionName="1.0" package="com.companyname.ehsanbest" android:installLocation="auto">
    <uses-sdk android:minSdkVersion="23" android:targetSdkVersion="30" />
    <uses-permission android:name="android.permission.RECORD_AUDIO" />
    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
    <uses-permission android:name="com.google.android.c2dm.permission.RECEIVE" />
    <uses-permission android:name="android.permission.READ_MEDIA_AUDIO" />
    <uses-permission android:name="android.permission.READ_MEDIA_IMAGES" />
    <uses-permission android:name="android.permission.READ_MEDIA_VIDEO" />
    <uses-permission android:name="android.permission.READ_USER_DICTIONARY" />

    <application 
        android:allowBackup="true" 
        android:icon="@mipmap/ic_launcher" 
        android:label="@string/app_name" 
        android:supportsRtl="true" 
        android:theme="@style/AppTheme"
        android:requestLegacyExternalStorage="true"></application>
</manifest>

    public class MainActivity : AppCompatActivity
    {
        Button _start;
        Button _stop;
        TextView _text1;
        TextView _text2;
        TextView _text3;
        MediaRecorder Recorder;
        static readonly int WRITE_EXTERNAL_STORAGE = 0;
        protected override void OnCreate(Bundle savedInstanceState)
        {
            base.OnCreate(savedInstanceState);
            Xamarin.Essentials.Platform.Init(this, savedInstanceState);
            // Set our view from the "main" layout resource
            SetContentView(Resource.Layout.activity_main);

            _start = FindViewById<Button>(Resource.Id.materialButton1);
            _stop = FindViewById<Button>(Resource.Id.materialButton2);
            _text1 = FindViewById<TextView>(Resource.Id.textView1);
            _text2 = FindViewById<TextView>(Resource.Id.textView2);
            _text3 = FindViewById<TextView>(Resource.Id.textView3);
            string path = Android.OS.Environment.ExternalStorageDirectory.AbsolutePath   "/esi2.txt";
            
            _start.Click  = (sender, e) =>
            {
                _stop.Enabled = !_stop.Enabled;
                _start.Enabled = !_start.Enabled;

                if (ActivityCompat.CheckSelfPermission(this, Android.Manifest.Permission.WriteExternalStorage) != Android.Content.PM.Permission.Granted)
                {
                    ActivityCompat.RequestPermissions(this, new String[] { Android.Manifest.Permission.Camera }, WRITE_EXTERNAL_STORAGE);
                }
                else
                {
                    ActivityCompat.RequestPermissions(this, new String[] { Android.Manifest.Permission.WriteExternalStorage }, 1);
                }
                
                _text2.Text = path.ToString();
                eCreateFile(path);
             };
 


        }
        public void eCreateFile(string FileName)
        {
            string text = "Ehsan Test";
            byte[] data = System.Text.ASCIIEncoding.ASCII.GetBytes(text);
            try
            {
                File.WriteAllBytes(FileName, data);
            }
            catch(Exception ex) 
            {
                _text3.Text = ex.Message;
            }
        }

probably I think function ActivityCompat.RequestPermissions(this, ) does nothing. Nothing happens when running it. While waiting for the permission window to open. but Nothing happens and Access is denied.

I installed the plugin Plugin.Permissions from nuget but nothing changes.

I did everything in answers in this stack overflow question:How to request permissions in Xamarin.Android?

but nothing

CodePudding user response：

In Xamarin.Android File Access / Reading or Writing to files on internal storage, code snippet shows how to get path with correct folder for your app:

var filePath = Path.Combine(System.Environment.GetFolderPath(System.Environment.SpecialFolder.Personal), "esi2.txt");