GridCustomDataSourceItemsOptions.SortInfo Property

Returns information about sort settings for selected items.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.Grid.v26.1.dll

NuGet Package: DevExpress.Blazor

Declaration

public IReadOnlyList<GridCustomDataSourceSortInfo> SortInfo { get; }

Property Value

Type	Description
IReadOnlyList<GridCustomDataSourceSortInfo>	A list of GridCustomDataSourceSortInfo objects.

Remarks

If standard data binding modes do not meet specific business requirements, you can implement your own data provider. To do so, create a GridCustomDataSource descendant and assign it to the Grid or TreeList component’s Data property.

The following code snippet implements a custom data provider’s GetItemsAsync method:

View Example: Custom Data Source Binding using Entity Framework Core

using DevExpress.Blazor;
using DevExpress.Data.Filtering;
using DevExpress.Data.Filtering.Helpers;
using CustomDataSource.Models;
using System.Collections;
using System.Linq.Expressions;
using DevExpress.Data.Linq;
using DevExpress.Data.Linq.Helpers;
using Microsoft.EntityFrameworkCore;

namespace CustomDataSource.Services;

public class OrdersDataSource : GridCustomDataSource, IDisposable {
    protected override Type DataItemType => typeof(Order);
    private readonly NorthwindContext _context;
    private bool _disposed = false;

    public OrdersDataSource(IDbContextFactory<NorthwindContext> contextFactory) {
        _context = contextFactory.CreateDbContext();
    } 
    // ...
    public override async Task<IList> GetItemsAsync(GridCustomDataSourceItemsOptions options, CancellationToken cancellationToken) {
        var filteredQuery = ApplyFiltering(options.FilterCriteria, _context.Orders);

        if (options.Count >= 0) {
            return await ApplySorting(options, filteredQuery)
                .Skip(options.StartIndex)
                .Take(options.Count)
                .ToListAsync(cancellationToken);
        }

        return await ApplySorting(options, filteredQuery).ToListAsync(cancellationToken);
    }
    // ...
    private static IQueryable<Order> ApplyFiltering(CriteriaOperator criteria, IQueryable<Order> queryableSource) {
        return !criteria.ReferenceEqualsNull()
            ? (IQueryable<Order>)queryableSource.AppendWhere(
                new CriteriaToEFExpressionConverter(queryableSource.Provider.GetType()), criteria)
            : queryableSource;
    }

    private static IQueryable<Order> ApplySorting(GridCustomDataSourceItemsOptions options, IQueryable<Order> queryableSource) {
        if (options.SortInfo != null) {
            foreach (var sortInfo in options.SortInfo) {
                queryableSource = SortByField(sortInfo.FieldName, sortInfo.DescendingSortOrder, queryableSource);
            }
        }

        return queryableSource;
    }

    private static IQueryable<Order> SortByField(string fieldName, bool descendingOrder, IQueryable<Order> queryableSource) {
        var lambda = GetTypedLambda(fieldName);
        if (queryableSource.Expression.Type != typeof(IOrderedQueryable<Order>)) {
            return !descendingOrder
                ? queryableSource.OrderBy(lambda)
                : queryableSource.OrderByDescending(lambda);
        }

        return !descendingOrder
            ? ((IOrderedQueryable<Order>)queryableSource).ThenBy(lambda)
            : ((IOrderedQueryable<Order>)queryableSource).ThenByDescending(lambda);
    }

    private static Expression<Func<Order, object>> GetTypedLambda(string fieldName) {
        var parameter = Expression.Parameter(typeof(Order));
        var property = Expression.Property(parameter, fieldName);
        var lambda = Expression.Lambda<Func<Order, object>>(Expression.Convert(property, typeof(object)), parameter);
        return lambda;
    }
    // ...
    public void Dispose() {
        Dispose(true);
        GC.SuppressFinalize(this);
    }

    protected virtual void Dispose(bool disposing) {
        if (!_disposed) {
            if (disposing) {
                _context?.Dispose();
            }
            _disposed = true;
        }
    }
    // ...
}

Related GitHub Examples

The following code snippet (auto-collected from DevExpress Examples) contains a reference to the SortInfo property.

Note

The algorithm used to collect these code examples remains a work in progress. Accordingly, the links and snippets below may produce inaccurate results. If you encounter an issue with code examples below, please use the feedback form on this page to report the issue.

C#

blazor-grid-custom-datasource-with-ef-core/CS/CustomDataSource/Services/OrdersDataSource.cs#L107

private static IQueryable<Order> ApplySorting(GridCustomDataSourceItemsOptions options, IQueryable<Order> queryableSource) {
    if (options.SortInfo != null) {
        foreach (var sortInfo in options.SortInfo) {