Knowledgebase

If you set your settings to the "Application" scope the settings will be read-only.

If you want to change these settings at runtime, you can use the following code from my unit test project:

First create a Settings class in your unit test project:

Right click on the unit test project and choose "Properties".

Click on "Settings":

Click on "This project does not contain a default settings file. Click here to create one."

At two test settings: "MyStringSetting" and "MyInSetting"":

The App.config will be changed like:

Now to show the code that changes the settings at runtime:

namespace UnitTestProject2
{
    using System;
    using Microsoft.VisualStudio.TestTools.UnitTesting;
    using UnitTestProject2.Properties;

    [TestClass]
    public class UnitTest1
    {
        [TestMethod]
        public void TestMethod1()
        {
            var settings = new Settings();
            
            Assert.AreEqual(settings.MyStringSetting, "This is some random text.");
            settings.ChangeSetting("MyStringSetting", "This is some other text.");
            Assert.AreEqual(settings.MyStringSetting, "This is some other text.");

            Assert.AreEqual(settings.MyIntSetting, 999);
            settings.ChangeSetting("MyIntSetting", 100);
            Assert.AreEqual(settings.MyIntSetting, 100);
        }
    }
    
}

namespace UnitTestProject2.Properties
{
    internal sealed partial class Settings
    {
        public void ChangeSetting<T>(string key, T value)
        {
            this[key] = value;
        }
    }
}