GetSection object cannot be cast to IDictionary<>

Question

I hope I'm just missing something simple. I need to read/write to a section of my exe.config file. I have this in my code:

var appConfiguration = ConfigurationManager.OpenExeConfiguration("Mytest.Console.exe");
var fileEnvironment = appConfiguration.GetSection("fileEnvironment");

and this is my app.config:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <configSections>
        <section name="fileEnvironment" type="System.Configuration.DictionarySectionHandler"/>
    </configSections>

    <fileEnvironment>
        <add key="TestEntry1" value="A nice value"/>
        <add key="TestEntry2" value="Another value"/>
    </fileEnvironment>
</configuration>

My appConfiguration variable is returned as {System.Configuration.Configuration} and the "HasFile" property is set to true.

Without casting my variable "fileEnvironment" is returned as System.Configuration.DefaultSection. When I add as IDictionary<string, string> to the GetSection method fileEnvironment is null.

Any ideas?

GetSection returns a ConfigurationSection, not a Dictionary, so nothing strange about that. What are you expecting to be able to do with the fileEnvironment variable? — Joachim Isaksson, Jan 21 '12 at 12:31
Have you check out this previous quesntion and answer... http://stackoverflow.com/questions/1278730/net-configurationmanager-app-config-confusion — Lloyd, Jan 21 '12 at 12:31
Yes, I read through that one. That's where I learned about DictionarySectionHandler. Anyway, I want to extract the entire fileEnvironment section as a dictionary, modify some parts of it, and save the entire dictionary back to the configuration file. Is it possible to do this? — JimBoone, Jan 21 '12 at 12:39
Why not create your own custom configuartion setting this is probably a better method to use? http://msdn.microsoft.com/en-us/library/ie/2tw134k3.aspx — Lloyd, Jan 21 '12 at 13:02
How do I pass the entire dictionary around to the rest of my application. I was hoping to add new entries to the dictionary and insert the new entries into the config file. Is this possible to do? — JimBoone, Jan 21 '12 at 13:11
I kept researching the dictionary issue and came up with [this stackoverflow topic](http://stackoverflow.com/questions/3935331/how-to-implement-a-configurationsection-with-a-configurationelementcollection)! It produces a collection instead of a dictionary, but points the way to a solution. Thanks for everyone's time. — JimBoone, Jan 21 '12 at 15:19

Kurt Hutchinson · Answer 1 · 2014-10-18T04:54:18.917

0

According to this old article, when a section is implemented using DictionarySectionHandler, ConfigurationManager.GetSection() will return a non-generic IDictionary, and not an IDictionary<T,V>. That's why your cast failed.

Although in modern times, it looks like it actually returns a HashTable.

edited Oct 18 '14 at 04:54

answered Oct 18 '14 at 04:49

Kurt Hutchinson

2,959
23
30

score 0 · Accepted Answer · edited May 23 '17 at 10:24

0

I kept researching the dictionary issue and came up with this stackoverflow Q&A! It produces a collection instead of a dictionary, but points the way to a solution. Thanks for everyone's time.

edited May 23 '17 at 10:24

Community

1
1

answered Jan 21 '12 at 20:54

JimBoone

554
1
7
27

GetSection object cannot be cast to IDictionary<>

2 Answers2