using static System.Console;
 
public class Program {
	public static void Main() {
		var pai = new Pai();
		WriteLine(pai.Metodo1(1).GetType());
		var filha = new Filha();
		WriteLine(filha.Metodo1(1).GetType());
		filha.PropriedadeB = "xxx";
		WriteLine(filha.Metodo1(1).GetType());
		var temp = filha.Metodo1(1);
		WriteLine(temp.PropriedadeB);
	}
}
 
public class Pai : Pai<Pai> { }
 
public class Pai<T> where T : Pai<T> {
    protected string PropriedadeA { get; set; }
    public T Metodo1(int valor) {
        //Vários procedimentos feitos aqui
        PropriedadeA = "Resultado do tratamento";
        return (T)this;
    }
}
 
public class Filha : Pai<Filha> {
	public string PropriedadeB { get; set; }
}
 
//https://pt.stackoverflow.com/q/47970/101

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