Unable to write files, not even in the editor! 🤬

Unity Engine
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1

What happened??? :face_with_symbols_over_mouth::face_with_symbols_over_mouth::face_with_symbols_over_mouth::face_with_symbols_over_mouth::face_with_symbols_over_mouth::face_with_symbols_over_mouth::face_with_symbols_over_mouth::face_with_symbols_over_mouth::face_with_symbols_over_mouth::face_with_symbols_over_mouth:
For several days now, all the instructions for writing files I have tried have given an error.
I created a very simple program: just a GO with this script attached

using System.Collections;
using System.Collections.Generic;
using System.IO;
using UnityEngine;

public class Myclass: MonoBehaviour
{
    // Start is called before the first frame update
    void Start()
    {
       
        Debug.Log(GetAndroidExternalStoragePath());
        File.WriteAllText(GetAndroidExternalStoragePath(),"MyText");
    }

    // Update is called once per frame
    void Update()
    {
        
    }
    private string GetAndroidExternalStoragePath()
    {
        if (Application.platform != RuntimePlatform.Android)
            return Application.persistentDataPath;

        var jc = new AndroidJavaClass("android.os.Environment");
        var path = jc.CallStatic<AndroidJavaObject>("getExternalStoragePublicDirectory",
            jc.GetStatic<string>("DIRECTORY_DCIM"))
            .Call<string>("getAbsolutePath");
        return path;
    }
}

Yet even running it in the editor, so without even getting to the android compilation, I get

UnauthorizedAccessException: Access to the path ‘C:\Users\me\AppData\LocalLow\DefaultCompany\write test’ is denied.
System.IO.FileStream…ctor (System.String path, System.IO.FileMode mode, System.IO.FileAccess access, System.IO.FileShare share, System.Int32 bufferSize, System.Boolean anonymous, System.IO.FileOptions options) (at <8ce0bd04a7a04b4b9395538239d3fdd8>:0)
System.IO.FileStream…ctor (System.String path, System.IO.FileMode mode, System.IO.FileAccess access, System.IO.FileShare share, System.Int32 bufferSize, System.IO.FileOptions options) (at <8ce0bd04a7a04b4b9395538239d3fdd8>:0)
(wrapper remoting-invoke-with-check) System.IO.FileStream…ctor(string,System.IO.FileMode,System.IO.FileAccess,System.IO.FileShare,int,System.IO.FileOptions)
System.IO.StreamWriter…ctor (System.String path, System.Boolean append, System.Text.Encoding encoding, System.Int32 bufferSize) (at <8ce0bd04a7a04b4b9395538239d3fdd8>:0)
System.IO.StreamWriter…ctor (System.String path) (at <8ce0bd04a7a04b4b9395538239d3fdd8>:0)
(wrapper remoting-invoke-with-check) System.IO.StreamWriter…ctor(string)
System.IO.File.WriteAllText (System.String path, System.String contents) (at <8ce0bd04a7a04b4b9395538239d3fdd8>:0)

Don’t tell me to check the write permissions, because of course I have them!

2

I am a little puzled

from your code, if running under windows/linux/mac would return the Application.persistentDataPath, have not added a file name to the path, therefore it cant create a no named file… This sounds like your issue rather than permissions

3

You’re right, that’s what happens when Unity starts generating nonsense error on your main project.

Now I tried following Managing External Files in Unity: A Step-by-Step Guide, page updated just 2 months ago, in the editor it works, it just doesn’t create any files on android.

I set the write permission to external and added to the manifest.

Well, I tried to visit it without an adblocker and realised that it is a bad page. And the contacts do not exist

4

Sadly I dont tend to do much with android, i mean i got a cheap tablet and made a tower defense to play on it, but nothing more… no files needed, in fact i didnt even save the score :stuck_out_tongue:

However, Id expect unity to honour the Application.persistentDataPath for android too, so a merge path while filename, and writealltext should then produce a file.

5 
// Start is called before the first frame update
void Start()
{
    try
    {
        string p = GetAndroidExternalStoragePath();

        Directory.CreateDirectory(p);


        
        Debug.Log(p);
        File.WriteAllText(Path.Combine(p, "n.log"), p + "\n" + System.DateTime.Now.ToString());


        Log = new StreamWriter(Path.Combine(p, "l.txt"), false);

        wLog("gklhuilrgyilsrg");
        wLog("u68678i578i");
        wLog("mvmcvgnv");

        Log.Close();
        txt.text = "f";
    }
    catch(Exception e)
    {
        txt.text = e.ToString();
    }
}

public void wLog(string t)
{
    Log.WriteLine(System.DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff") + " " + t);
    Log.Flush();
}

// Update is called once per frame
void Update()
{
    
}
private string GetAndroidExternalStoragePath()
{
    if (Application.platform != RuntimePlatform.Android)return Application.persistentDataPath;

    
    var jc = new AndroidJavaClass("android.os.Environment");
    var path = jc.CallStatic<AndroidJavaObject>("getExternalStoragePublicDirectory",
        jc.GetStatic<string>("DIRECTORY_DOCUMENTS"))
        .Call<string>("getAbsolutePath");

    path = Path.Combine(path, "me", "test"); 

    return path;
}

works on android 6.
on android 14 instead it creates folders but not files

<?xml version="1.0" encoding="utf-8"?>
<manifest
    xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.unity3d.player"
    xmlns:tools="http://schemas.android.com/tools">
    <application>
        <activity android:name="com.unity3d.player.UnityPlayerActivity"
                  android:theme="@style/UnityThemeSelector">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
            <meta-data android:name="unityplayer.UnityActivity" android:value="true" />
        </activity>
    </application>
    <uses-permission android:name="android.permission.INTERNET" />
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
	<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
	<uses-permission android:name="android.permission.MANAGE_EXTERNAL_STORAGE" />

</manifest>
6

have you debugged the path it creates? If you make a path with /me/test at the end, have you tried ensuring that the folder me is made first, and then making the file in it?

7

The error is just because it’s an invalid path. You probably need to include a file extension.

8

Yes, the path is correct. On android 14 it creates the correct folder path, but does not create the file.
On android 6, on the other hand, it works correctly.

9

Again, probably because there’s no extension. The editor error, which is coming from the Microsoft side of things is because it thinks you’re trying to write data to a folder, which will result in the error you’re getting.