从类中的集合字段获取值

我需要从属性/字段中获取集合类型的数据，并最终把它显示在表格上。我该怎么做？

下面的代码解释了我试图做的事情和我遇到的错误，希望它有意义。

public class C
{
    public string Id { get; set; }
    //public List<string> ColVal { get; }
    public C()
    {}
    public C(ObjectA objVar)
    {
        Id = objVar.Id;
        //ColVal = objVar.ColVals; //<- Errors out: This is a collection type property, how do I get values & solve this?
    }
}

public string Id { get; set; }
public List<string> ColVal { get; set; }
public C()
{}
public C(C objVar)
{
    Id = objVar.Id;
   ColVal = objVar.ColVal; //<- Errors out: This is a collection type property, how do I get values & solve this?
}
}