[This is preliminary documentation and is subject to change.]

Represents a filter or a part of a filter.

Namespace:  Firefly.Box.Data.Advanced
Assembly:  Firefly.Box (in Firefly.Box.dll) Version: 3.4.23.6473 (3.4.23.6473)

Syntax

C#
public abstract class FilterBase
Visual Basic (Declaration)
Public MustInherit Class FilterBase
Visual C++
public ref class FilterBase abstract

Remarks

This filter can later be used as the Where of a UIController, a BusinessProcess a Relation etc... Insert demo here

Examples

filter usage
This example is in the form of Unit Tests. It references the NUnit framework. This framework can be downloaded from www.NUnit.org. For more information about unit testing visit: www.NUnit.org.
This example is based on test data. The code for the entities included in this test data can be found in the documentation of Entity
CopyC#
using System;
using System.Collections.Generic;
using System.Text;
using Firefly.Box.Data.Advanced;
using NUnit.Framework;
using Firefly.Box;
using Firefly.Box.Testing;

namespace TestFirefly.Box.Documentation
{
    [TestFixture]
    public class WhereUsage
    {
        [Test]
        public void SimpleWhere()
        {
            var employees = new Pubs.Employees();
            employees.InitializeWithTestData();

            var bp = new BusinessProcess
                         {
                             From = employees
                         };
            bp.Where.Add(employees.JobLevel.IsEqualTo(150));
            bp.Run();
            bp.Counter.ShouldBe(3);
        }
        [Test]
        public void AddingTwoFiltersBehavesAsAndWould()
        {
            var employees = new Pubs.Employees();
            employees.InitializeWithTestData();

            var bp = new BusinessProcess
            {
                From = employees
            };
            bp.Where.Add(employees.JobLevel.IsEqualTo(150));
            bp.Where.Add(employees.JobId.IsLessThan(9));
            bp.Run();
            bp.Counter.ShouldBe(1);
        }
        [Test]
        public void UsingAndAndOr()
        {
            var employees = new Pubs.Employees();
            employees.InitializeWithTestData();

            var bp = new BusinessProcess
            {
                From = employees
            };
            bp.Where.Add(employees.JobLevel.IsEqualTo(150).And(
                        employees.JobId.IsLessThan(9).Or(
                        employees.MiddleInitial.IsEqualTo("C"))));
            bp.Run();
            bp.Counter.ShouldBe(2);
        }
        [Test]
        public void SendingDirectStringToTheDB()
        {
            var employees = new Pubs.Employees();
            employees.InitializeWithTestData();
            var bp = new BusinessProcess
                         {
                             From = employees
                         };
            bp.Where.Add("{0} in ({1},{2},{3})",employees.MiddleInitial, "M", "R", "A");
            bp.Run();
            bp.Counter.ShouldBe(9);
        }
        [Test]
        public void UsingCustomInMemoryFilter()
        {
            var employees = new Pubs.Employees();
            employees.InitializeWithTestData();
            var bp = new BusinessProcess
            {
                From = employees
            };
            //This has a slight performance penalty as this condition is evaluated in memory, and not by the database
            bp.Where.Add(() => employees.MiddleInitial == "M" || employees.MiddleInitial == "R" || employees.MiddleInitial == "A");
            bp.Run();
            bp.Counter.ShouldBe(9);
        }
        [Test]
        public void UsingAPreDefinedFilter()
        {
            var employees = new Pubs.Employees();
            employees.InitializeWithTestData();
            var bp = new BusinessProcess
            {
                From = employees
            };
            FilterCollection filter = new FilterCollection();
            filter.Add(employees.JobLevel.IsEqualTo(150));
            filter.Add(employees.JobId.IsLessThan(9));

            bp.Where.Add(filter);
            bp.Run();
            bp.Counter.ShouldBe(1);
        }
    }
}

Inheritance Hierarchy

See Also