How to get a List collection of values from app.config in WPF?

Question

The following example fills the ItemsControl with a List of BackupDirectories which I get from code.

How can I change this

Answer 1

Thank for the question. But I have found my own solution to this problem. At first, I created a method

    public T GetSettingsWithDictionary<T>() where T:new()
    {
        IConfigurationRoot _configurationRoot = new ConfigurationBuilder()
        .AddXmlFile($"{Assembly.GetExecutingAssembly().Location}.config", false, true).Build();

        var instance = new T();
        foreach (var property in typeof(T).GetProperties())
        {
            if (property.PropertyType == typeof(Dictionary<string, string>))
            {
                property.SetValue(instance, _configurationRoot.GetSection(typeof(T).Name).Get<Dictionary<string, string>>());
                break;
            }

        }
        return instance;
    }

Then I used this method to produce an instance of a class

var connStrs = GetSettingsWithDictionary<AuthMongoConnectionStrings>();

I have the next declaration of class

public class AuthMongoConnectionStrings
{
    public Dictionary<string, string> ConnectionStrings { get; set; }
}

and I store my setting in App.config

<configuration>    
  <AuthMongoConnectionStrings
  First="first"
  Second="second"
  Third="33" />
</configuration> 

Answer 2

In App.config:

<add key="YOURKEY" value="a,b,c"/>

In C#:

string[] InFormOfStringArray = ConfigurationManager.AppSettings["YOURKEY"].Split(',').Select(s => s.Trim()).ToArray();
List<string> list = new List<string>(InFormOfStringArray);

Answer 3

You can create your own custom config section in the app.config file. There are quite a few tutorials around to get you started. Ultimately, you could have something like this:

<configSections>
    <section name="backupDirectories" type="TestReadMultipler2343.BackupDirectoriesSection, TestReadMultipler2343" />
  </configSections>

<backupDirectories>
   <directory location="C:\test1" />
   <directory location="C:\test2" />
   <directory location="C:\test3" />
</backupDirectories>

To complement Richard's answer, this is the C# you could use with his sample configuration:

using System.Collections.Generic;
using System.Configuration;
using System.Xml;

namespace TestReadMultipler2343
{
    public class BackupDirectoriesSection : IConfigurationSectionHandler
    {
        public object Create(object parent, object configContext, XmlNode section)
        {
            List<directory> myConfigObject = new List<directory>();

            foreach (XmlNode childNode in section.ChildNodes)
            {
                foreach (XmlAttribute attrib in childNode.Attributes)
                {
                    myConfigObject.Add(new directory() { location = attrib.Value });
                }
            }
            return myConfigObject;
        }
    }

    public class directory
    {
        public string location { get; set; }
    }
}

Then you can access the backupDirectories configuration section as follows:

List<directory> dirs = ConfigurationManager.GetSection("backupDirectories") as List<directory>;

Answer 4

There's actually a very little known class in the BCL for this purpose exactly: CommaDelimitedStringCollectionConverter. It serves as a middle ground of sorts between having a ConfigurationElementCollection (as in Richard's answer) and parsing the string yourself (as in Adam's answer).

For example, you could write the following configuration section:

public class MySection : ConfigurationSection
{
    [ConfigurationProperty("MyStrings")]
    [TypeConverter(typeof(CommaDelimitedStringCollectionConverter))]
    public CommaDelimitedStringCollection MyStrings
    {
        get { return (CommaDelimitedStringCollection)base["MyStrings"]; }
    }
}

You could then have an app.config that looks like this:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <section name="foo" type="ConsoleApplication1.MySection, ConsoleApplication1"/>
  </configSections>
  <foo MyStrings="a,b,c,hello,world"/>
</configuration>

Finally, your code would look like this:

var section = (MySection)ConfigurationManager.GetSection("foo");
foreach (var s in section.MyStrings)
    Console.WriteLine(s); //for example

Answer 5

Had the same problem, but solved it in a different way. It might not be the best solution, but its a solution.

in app.config:

<add key="errorMailFirst" value="test@test.no"/>
<add key="errorMailSeond" value="krister@tets.no"/>

Then in my configuration wrapper class, I add a method to search keys.

        public List<string> SearchKeys(string searchTerm)
        {
            var keys = ConfigurationManager.AppSettings.Keys;
            return keys.Cast<object>()
                       .Where(key => key.ToString().ToLower()
                       .Contains(searchTerm.ToLower()))
                       .Select(key => ConfigurationManager.AppSettings.Get(key.ToString())).ToList();
        }

For anyone reading this, i agree that creating your own custom configuration section is cleaner, and more secure, but for small projects, where you need something quick, this might solve it.

Answer 6

You could have them semi-colon delimited in a single value, e.g.

App.config

<add key="paths" value="C:\test1;C:\test2;C:\test3" />

C#

var paths = new List<string>(ConfigurationManager.AppSettings["paths"].Split(new char[] { ';' }));