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devconcept
Asked: 2020-08-06 06:29:49 +0800 CST 2020-08-06 06:29:49 +0800 CST

How to know if a method or property is being overridden

  • 772

I have a class that only defines some public properties but has a long chain of inheritance.

public class AgencyPaginatedQuery : SortedPaginatedQuery
{
    public string Code { get; set; }
    public string Name { get; set; }
    public string Initials { get; set; }
}

public class SortedPaginatedQuery : PaginatedQuery
{
    public string Sort { get; set; }
    public string Order { get; set; }
}


public class PaginatedQuery
{
    public int? Start { get; set; }
    public int? Size { get; set; }
}

The class I am looking at is AgencyPaginatedQueryand I am trying to get the names of said properties using LINQ and Reflection. So far I have been able to get which of these properties belong to the class in question with a simple query

var type = typeof(AgencyPaginatedQuery);
var names = from prop in type.GetProperties()
            where prop.DeclaringType.Name == type.Name &&
                  prop.MemberType == System.Reflection.MemberTypes.Property
            select prop.Name;

this brings me back

[0] = "Code" 
[1] = "Name" 
[2] = "Initials"

But now I need to filter from that list the properties that are overridden in case I write

public class AgencyPaginatedQuery : SortedPaginatedQuery
{
    public string Code { get; set; }
    public string Name { get; set; }
    public string Initials { get; set; }
    public override string Sort { get; set; }
}

this last property Sortdoes not appear in the list.

How can I know if the property has a overrideusing my query?

PS: I know I have to mark the property in the base class as virtual for this to work.

c#

1 Answers

  1. Best Answer

    I'll give you a way to check it byGetBaseDefinition()

    Using the flag BindingFlags.DeclaredOnlyignores inherited members.

    Type type = typeof(AgencyPaginatedQuery);

foreach ( var property in type.GetProperties(BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly)) {
    var getMethod = property.GetGetMethod(false);
    if (getMethod.GetBaseDefinition() == getMethod) {
        Console.WriteLine(getMethod);
    }
}

    if the property is overridden MethodInfothe getter will be different MethodInfofromGetBaseDefinition()

    You could get it this way:

    var names = from prop 
              in type.GetProperties(BindingFlags.Public | BindingFlags.Instance | BindingFlags.DeclaredOnly)
             let getMethod = prop.GetGetMethod(false)
           where getMethod.GetBaseDefinition() == getMethod
          select prop.Name;

    As a result I get:

    Code
    Name
    Initials

    • 1