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======= the best trick: subtypes of =======

>I need to just derive stuff from something, and all the derived types I'll register somewhere, or initialize, or something like that - but I don't want to also have to have an ever-growing list of tasks for each  

<code csharp>
var subtypes = AppDomain.CurrentDomain.GetAssemblies()
    .SelectMany(domainAssembly => domainAssembly.GetTypes())
    .Where(type => type.IsSubclassOf(typeof(MyAbstractClass)) && !type.IsAbstract)
    .ToList();

foreach (var subtype in subtypes)
{
    var instance = (MyAbstractClass) Activator.CreateInstance(subtype);
}
</code>

so you make an abstract class ''MyAbstractClass'' and derive from it. 


====== example ======

<code csharp>
static List<Task<Report>> CollectReporters(Configuration conf)
{
    var toReturn = new List<Task<Report>>();

    var reporterTypes = AppDomain.CurrentDomain.GetAssemblies()
      .SelectMany(domainAssembly => domainAssembly.GetTypes())
      .Where(type => type.IsSubclassOf(typeof(newsletter.Reporters.Reporter)) && !type.IsAbstract)
      .ToList();
    var skipPortionInName = "newsletter.Reporters.".Length;


    foreach(var discoveredConfType in conf.Reporters.Select(r => r.ReporterClass))
    {
        Console.WriteLine($"{discoveredConfType} configuration type discovered");
    }
    foreach (var reporterType in reporterTypes)
    {
        Console.WriteLine($"{reporterType.ToString().Substring(skipPortionInName).ToLower()} reporter class discovered");
        Func<Configuration.Reporter, bool> predicate = r => r.ReporterClass == reporterType.ToString().Substring(skipPortionInName).ToLower();
        if (!conf.Reporters.Any(predicate))
        {
            Console.WriteLine($"no configurations for it");
        }
        else
        {
            var configurationsFor = conf.Reporters.Where(predicate);
            Console.WriteLine($"{configurationsFor.Count()} configurations for it");
            
            foreach (var confFor in configurationsFor)
            {
                 var instance = (newsletter.Reporters.Reporter) Activator.CreateInstance(reporterType);
                toReturn.Add(instance.Report(confFor));
            }
        }
    }

    return toReturn;
}
</code>

observe - I write a text string in a config file to describ ea type, and now I can pick what object to instantiate :)))

======= nuget on non-windows =======

this comes up a lot.

> it's easy just install it via nuget with <code>Install-Package WebDav.Client</code>

- normal devs

for some reason, it works differently when you're not on windows. what we do:

<code>dotnet add package WebDav.Client</code>

why is not ''dotnet nuget Install-Package WebDav.Client''? why does //the quintessential nuget function// not involve the word "nuget"? All I got for you is a nice big shrug.

======= entityframework (my beloved) =======

install in your dev env:

  dotnet tool install --global dotnet-ef

install packages:
  * Microsoft.EntityFrameworkCore.Design
  * Npgsql.EntityFrameworkCore.PostgreSQL (or whatever you like)

  dotnet-ef dbcontext scaffold "Host=HOST;Database=DBNAME;Username=USERNAMEPassword=PASSWORD;IncludeErrorDetail=true;" Npgsql.EntityFrameworkCore.PostgreSQL


migrations:
  dotnet ef migrations add "name of migration"
  dotnet ef database update --connection "Host=asdfasdfasdf etc"

======= enum names =======

forget "switch(enum) return string" functions, do it with decorators! https://stackoverflow.com/questions/479410/enum-tostring-with-user-friendly-strings

make yourself this function:
<code csharp>
public static string GetDescription<T>(this T enumerationValue)
    where T : struct
{
    Type type = enumerationValue.GetType();
    if (!type.IsEnum)
    {
        throw new ArgumentException("EnumerationValue must be of Enum type", "enumerationValue");
    }

    //Tries to find a DescriptionAttribute for a potential friendly name
    //for the enum
    MemberInfo[] memberInfo = type.GetMember(enumerationValue.ToString());
    if (memberInfo != null && memberInfo.Length > 0)
    {
        object[] attrs = memberInfo[0].GetCustomAttributes(typeof(DescriptionAttribute), false);

        if (attrs != null && attrs.Length > 0)
        {
            //Pull out the description value
            return ((DescriptionAttribute)attrs[0]).Description;
        }
    }
    //If we have no description attribute, just return the ToString of the enum
    return enumerationValue.ToString();
}
</code>

and then all you have to do is use ''Description'' from ''System.ComponentModel'':
<code csharp>
private enum PublishStatusValue
{
    [Description("Not Completed")]
    NotCompleted,
    Completed,
    Error
};
</code>

======= what is the actual publish command =======

specify output folder. I don't know what all the other bullshit it insists on dumping in the folder is.

<code>
dotnet publish -c Release -o ../publish
</code>

also you can't not get ''appsettings.Development.json'' to show up in release. your only option is to delete it manually.
======= why is asp.net not accepting my frombody thing? =======

microsoft replaced the working json parser with one that doesn't. https://devblogs.microsoft.com/dotnet/try-the-new-system-text-json-apis/

fix: 
  - ''dotnet add package Microsoft.AspNetCore.Mvc.NewtonsoftJson --version [compatible version]''
  - go find where services are being added; ''services.AddControllers().AddNewtonsoftJson();''. (hint: Builder.Services?)

======= which is a field, which is a property? =======

<code csharp>
public class MyClass
{
    // this is a field.  It is private to your class and stores the actual data.
    private string _myField;

    // this is a property. When accessed it uses the underlying field,
    // but only exposes the contract, which will not be affected by the underlying field
    public string MyProperty
    {
        get
        {
            return _myField;
        }
        set
        {
            _myField = value;
        }
    }

    // This is an AutoProperty (C# 3.0 and higher) - which is a shorthand syntax
    // used to generate a private field for you
    public int AnotherProperty { get; set; } 
}
</code>

src: https://stackoverflow.com/a/295109/1173856
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