[Parameter]
public EventCallback<IEnumerable<TValue>> ValuesChanged { get; set; }

@using Data

<DxListBox Data="@Staff.DataSource"
           TextFieldName="@nameof(Person.Text)"
           Values="@Values"
           ValuesChanged="@((IEnumerable<Person> values) => ValuesChanged(values))">
</DxListBox>

@code {
    IEnumerable<Person> Values { get; set; }

    void ValuesChanged(IEnumerable<Person> values) {
        Values = values;
        InvokeAsync(StateHasChanged);
    }
}

using System;
using System.Collections.Generic;

namespace BlazorProject.Data {
    public static class Staff {
        private static readonly Lazy<List<Person>> dataSource = new Lazy<List<Person>>(() => {
            var dataSource = new List<Person>() {
                new Person() { Id= 0 , FirstName="John", LastName="Heart", Department=Department.Electronics },
                new Person() { Id= 1 , FirstName="Samantha", LastName="Bright", Department=Department.Motors },
                new Person() { Id= 2 , FirstName="Arthur", LastName="Miller", Department=Department.Software },
                new Person() { Id= 3 , FirstName="Robert", LastName="Reagan", Department=Department.Electronics },
                new Person() { Id= 4 , FirstName="Greta", LastName="Sims", Department=Department.Motors },
                new Person() { Id= 5 , FirstName="Brett", LastName="Wade", Department=Department.Software },
                new Person() { Id= 6 , FirstName="Sandra", LastName="Johnson", Department=Department.Electronics },
                new Person() { Id= 7 , FirstName="Edward", LastName="Holmes", Department=Department.Motors },
                new Person() { Id= 8 , FirstName="Barbara", LastName="Banks", Department=Department.Software },
                new Person() { Id= 9 , FirstName="Kevin", LastName="Carter", Department=Department.Electronics },
                new Person() { Id= 10, FirstName="Cynthia", LastName="Stanwick", Department=Department.Motors },
                new Person() { Id= 11, FirstName="Sam", LastName="Hill", Department=Department.Electronics }};
            return dataSource;
        });
        public static List<Person> DataSource { get { return dataSource.Value; } }
    }

    public class Person {
        public int Id { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public Department Department { get; set; }

        public string Description => $"{FirstName} {LastName} ({Department} Dept.)";

        public override bool Equals(object obj) {
            if(obj is Person person) {
                if(person.Id != Id)
                    return false;
                return string.Equals(person.FirstName, FirstName) && string.Equals(person.LastName, LastName);
            }
            return false;
        }

        public override int GetHashCode() {
            return HashCode.Combine(Id, FirstName, LastName);
        }
    }
}