Question

I am writing code that read customized config section from app.config, but I get some errors, hope anyone can help to fig out.

<?xml version="1.0"?>
<configuration>
  <configSections>
    <section name="Psptune" 
             type="ConfigurationSettings.PsptuneSection, ConfigurationSettings"/>
  </configSections>
  <Psptune>
    <psp>
      <FolderLocataions>
        <add name="PspFolder" directory="aa"/>
        <add name="IsoFolder" directory="aa"/>
      </FolderLocataions>
    </psp>
  </Psptune>
  <startup>
    <supportedRuntime version="v4.0" 
                      sku=".NETFramework,Version=v4.0"/>
  </startup>
</configuration>


using System;

namespace ConfigurationSettings
{
    class Program
    {
        static void Main(string[] args)
        {
            try
            {
                var sec = PsptuneSection.Settings;
            }
            catch (Exception exception)
            {
                Console.WriteLine(exception);
            }
            Console.ReadKey();
        }
    }
}
using System.Configuration;

namespace ConfigurationSettings
{
    public class FolderLocationElement : ConfigurationElement
    {
        [ConfigurationProperty( "name", DefaultValue = "default", IsRequired = false)]
        [StringValidator(MinLength = 5, MaxLength = 256)]
        public string Name
        {
            get { return (string) this["name"]; }
            set { this["name"] = value;  }
        }

        [ConfigurationProperty("directory", DefaultValue = "default", IsRequired = false)]
        [StringValidator(MinLength = 5, MaxLength = 256)]
        public string Directory
        {
            get { return (string)this["directory"]; }
            set { this["directory"] = value; }
        }

    }
}

using System.Configuration;

namespace ConfigurationSettings
{
    public class FolderLocationElementCollection : ConfigurationElementCollection
    {
        protected override ConfigurationElement CreateNewElement()
        {
            return new FolderLocationElement();
        }

        protected override object GetElementKey(ConfigurationElement element)
        {
            return ((FolderLocationElement) element).Name;
        }

        public FolderLocationElement this[int index]
        {
            get { return (FolderLocationElement) BaseGet(index); }
        }

        public void Add(FolderLocationElement element)
        {
            BaseAdd(element);
        }
    }
}

using System.Configuration;

namespace ConfigurationSettings
{
    public class PspElement : ConfigurationElement
    {
        [ConfigurationProperty("FolderLocataions", DefaultValue = "default", IsRequired = false)]
        [StringValidator(MinLength = 5, MaxLength = 256)]
        public FolderLocationElementCollection FolderLocataions
        {
            get { return (FolderLocationElementCollection) this["FolderLocataions"]; }
            set { this["FolderLocataions"] = value; }
        }
    }
}

using System.Configuration;

namespace ConfigurationSettings
{
    public class PsptuneSection : ConfigurationSection
    {
        private static PsptuneSection _settings =
            ConfigurationManager.GetSection("Psptune") as PsptuneSection;

        public static PsptuneSection Settings { get { return _settings;  } }

        [ConfigurationProperty("psp", DefaultValue = "default", IsRequired = false)]
        public PspElement Psp
        {
            get { return (PspElement) this["psp"]; }
            set { this["psp"] = value; }
        }
    }
}

The exeception I get is:

System.TypeInitializationException: The type initializer for 'ConfigurationSetti
ngs.PsptuneSection' threw an exception. ---> System.Configuration.ConfigurationE
rrorsException: The default value of the property 'psp' cannot be parsed. The er
ror is: Object reference not set to an instance of an object.

Answer 1

Nevermind my friends i got it figure out, and you ppl can stop to vote me down. The problem is some of the element can not have default value