How To Access Class Properties From A Base Abstract Class

I'm trying to design a base abstract class that can gather all the properties from classes that are inherited from it. I'm getting the name fine, but getting the value is not working. I get the runtime error "Object does not match target". Any help is much appreciated.

public string Get()
{
    string ret = "";
    var type = GetType();
    foreach (PropertyInfo p in this.GetType().GetProperties())
    {
        ret += p.Name + "`" + p.GetValue(type) + "~";
        //i've also tried
        //ret += p.Name + "`" + p.GetValue(this) + "~";
    }
    ret = ret.TrimEnd('~');
    return ret;
}

> Parameter count mismatch.

It seems that one of the properties is an indexer, you can ignore such properties by checking GetIndexParameters on the PropertyInfo (or process it accordingly if needed):

if (!p.GetIndexParameters().Any())
{
    ret += p.Name + "`" + p.GetValue(this) + "~";
}

Demo with the runtime exception @sharplab.io.

You need to pass the object you want to get property values from

p.GetValue(this)

When working with arbitrary classes, we should take into account, that we can have

• static properties: public static int MyId => 3;
• Indexers public int this[int index] { get => index;}
• Write only properties public int MyId {set => m_Id = value;}

So far so good, let's query the properties:

using System.Linq;
...
public string Get() => string.Join("~", GetType()
  .GetProperties()
  .Where(prop => prop.CanRead)                            // readable
  .Where(prop => !prop.GetGetMethod().IsStatic)           // instance  
  .Where(prop => prop.GetIndexParameters().Length == 0)   // not an indexer
  .Select(prop => $"{prop.Name} `{prop.GetValue(this)}"));

Another issue is string manipulations: if you have a lot of properties (long ret) adding strings can be slow. If you want to join strings, just put string.Join.