IModelStore<TModel>.OrderByDescending<TKey>(Func<TModel, object> keySelector) Method

.NET Standard 2.x | Current Version (1.0.1)

0.5.0-alpha

1.0.1 (current)

Sorts the model objects in ModelStore in the descending order according to a key.

It returns an IOrderable<TModel> object. You need to execute the IOrderabe<TModel>.Sort method to actually sort the data.

Namespace: PowerBuilder.Data

Assembly: PowerBuilder.Data.dll

Syntax

  public IOrderable<TModel> OrderByDescending<TModel>(Func<TModel, object> keySelector);

Type Parameters

TKey

The datatype of the key.

Parameters

keySelector System.Func<TModel,TKey>

A function to extract a key from a model object.

Returns

SnapObjects.Data.IOrderable<TModel>

Returns an IOrderable<TModel> object which provides methods to add other sorting conditions or execute sort.

Examples

The following code example demonstrates how to sort the data in ModelStore by Department ID in the descending order.

using Appeon.ApiDoc.Models.School;
using System;
using PowerBuilder.Data;

namespace Appeon.ApiDoc.IModelStoreExamples
{
    public class OrderByDescendingExample
    {
        private readonly SchoolContext _context;

        public OrderByDescendingExample(SchoolContext dataContext)
        {
            // Sets the data context
            _context = dataContext;
        }

        public void Example()
        {
            var courses = new ModelStore<Course>();

            // Retrieves data.
            courses.Retrieve(_context);

            // Shows the Department ID before sorted
            Console.WriteLine("Before Sorted: ");
            foreach (var course in courses)
            {
                Console.WriteLine("Department ID: {0}", course.DepartmentID);
            }

            // Sets to sort by DepartmentID in descending order.
            var order = courses.OrderByDescending(m => m.DepartmentID);

            order.Sort();

            // Shows the Department ID after sorted
            Console.WriteLine("After Sorted: ");
            foreach (var m in courses)
            {
                Console.WriteLine("Department ID: {0}", m.DepartmentID);
            }

            /* This code example produces the following output:
             
            Before Sorted:
            Department ID: 7
            Department ID: 1
            Department ID: 1
            Department ID: 2
            Department ID: 2
            Department ID: 2
            Department ID: 7
            Department ID: 4
            Department ID: 4
            Department ID: 4
            Department ID: 7

            After Sorted:
            Department ID: 7
            Department ID: 7
            Department ID: 7
            Department ID: 4
            Department ID: 4
            Department ID: 4
            Department ID: 2
            Department ID: 2
            Department ID: 2
            Department ID: 1
            Department ID: 1
            */
        }
    }
}

Example Refer To

Model Class: Course

Applies to

.NET Standard

2.x