DataDirectory is not getting replaced in my code WPF - app.config

Question

I've been trying to set a connectionstring to the users programdata folder and followed the first step in the answer of this post:

%APPDATA% in connection string is not substituted for the actual folder?

Unfortunately I can't get it to work:

In the onstartup method of my WPF application I run the following:

AppDomain.CurrentDomain.SetData("DataDirectory", Environment.GetFolderPath(Environment.SpecialFolder.CommonApplicationData));

var test = AppDomain.CurrentDomain.GetData("DataDirectory");

var connection = System.Configuration.ConfigurationManager.ConnectionStrings["Conn"].ConnectionString;

Value in App.config

<add name="Conn" connectionString="data source=|DataDirectory|\mydb" providerName="System.Data.SQLite" />

result of test = "c:\programdata" => this is good

result of connectionstring ="|DataDirectory|\mydb" => this is not good

I'm expecting: "c:\programdata\mydb"

I've been looking all around... what am I doing wrong?

thanks in advance,

Answer 1

You are misunderstanding how it works.
Setting the DataDirectory is correct, but the actual connectionstring is not changed on file.
When you open the connection the |DataDirectory| part of the string will be replaced with your path

You just need to try and see by yourself

Answer 2

If you're following the answer you linked to, you seem to be missing the following from Step 2. in the link:

 return connection.Replace("%APPDATA%",
    Environment.GetFolderPath(Environment.SpecialFolder.ApplicationData));