使用JavaScript在本地应用程序（无服务器）中读取/写入和存储数据

Question

So I am making a local App using Javascript , React and Electron and I want it to be able to work just fine without internet.

I can't use ' localStorage ' because the data might get deleted if the user deletes the cache.

I tried reading/writing using differant Modules, none of them worked mostly because of CROS. Using XMLHTTPrequests and Ajax doesn't work either and am running out of time.

When I use them on the test server, they return the index.html for the mainpage (They can at least access that ... and still they can't read the data) but when I try it on the build I get CORS the error.

My Idea for now is to enable CORS on my webpage since I have no worries about security : The App will run ONLY offline so there is no danger. But After many hours...I didn't find a solution to do it on the client side.

If anyone has an idea or suggestion I would be grateful.

I tried : fs,FileReader,FileSaver, $.ajax,XMLHTTPrequests

 //using $ajax
 var test = $.ajax({
        crossDomain:true,
        type: 'GET',
        url:'../data/DefaultCategorie.txt',
        contentType: 'text/plain',
        success: function(data){
            console.log(data);
        },
        error: function(){
            alert('failed');
        },

    })

 //using fs
 fs.readFile('../data/DefaultCategorie.txt', 'utf8', (err, data) => {
        if (err) {
            console.log("Failed");
            throw err
        }
        console.log(data);
        fs.close(data, (err) => {
          if (err) throw err;
        });
      });

Answer 1

This article covers the 3 most common ways to store user data: How to store user data in Electron

The Electron API for appData does what you want. It is very easy to use.

From the above article:

const userDataPath = (electron.app || electron.remote.app).getPath('userData');
this.path = path.join(userDataPath, opts.configName + '.json')
this.data = parseDataFile(this.path, opts.defaults);   

---

function parseDataFile(filePath, defaults) {

  try {
    return JSON.parse(fs.readFileSync(filePath));
  } catch(error) {
    // if there was some kind of error, return the passed in defaults instead.
    return defaults;
  }
}

---

Docs

app.getPath(name)

 name String 

Returns String - A path to a special directory or file associated with name. On failure, an Error is thrown.

You can request the following paths by the name:

 appData - Per-user application data directory, which by default points to: %APPDATA% on Windows $XDG_CONFIG_HOME or ~/.config on Linux ~/Library/Application Support on macOS userData - The directory for storing your app's configuration files, which by default it is the appData directory appended with your app's name.