DxGrid.PageSizeChanged Event

Fires when the page size changes.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v24.1.dll

NuGet Package: DevExpress.Blazor

Declaration

[Parameter]
public EventCallback<int> PageSizeChanged { get; set; }

Parameters

Type	Description
Int32	A new PageSize property value.

Remarks

The PageSizeChanged event fires each time the PageSize property value changes. The event is handled automatically when you use two-way data binding for the PageSize property (@bind-PageSize).

You can also handle this event to create a custom response to page size changes.

The following example displays an informational message when a user selects a new value in the page size selector.

Razor

@using Microsoft.EntityFrameworkCore
@inject IDbContextFactory<NorthwindContext> NorthwindContextFactory
@implements IDisposable

<div><b>@PageSizeInfo</b></div>

<DxGrid Data="@Data"
        PageSize="@PageSize"
        PageSizeSelectorVisible="true"
        PageSizeSelectorItems="@(new int[] { 5, 10, 15 })"
        PageSizeChanged="OnPageSizeChanged">
    <Columns>
        <DxGridDataColumn FieldName="ShipName" />
        <DxGridDataColumn FieldName="ShipCity" />
        <DxGridDataColumn FieldName="ShipCountry" />
        <DxGridDataColumn FieldName="Freight" />
        <DxGridDataColumn FieldName="OrderDate" />
        <DxGridDataColumn FieldName="ShippedDate" />
    </Columns>
</DxGrid>

@code {
    object Data { get; set; }
    NorthwindContext Northwind { get; set; }
    int PageSize { get; set; } = 10;
    string PageSizeInfo { get; set; } = "Page size is 10";

    protected override void OnInitialized() {
        Northwind = NorthwindContextFactory.CreateDbContext();
        Data = Northwind.Orders.ToList();
    }

    void OnPageSizeChanged(int newPageSize) {
        PageSizeInfo = "Page size was changed from " + PageSize + " to " + newPageSize;
        PageSize = newPageSize;
    }

    public void Dispose() {
        Northwind?.Dispose();
    }
}

Order

using System;
using System.Collections.Generic;

#nullable disable

namespace Grid.Northwind {
    public partial class Order {
        public Order() {
            OrderDetails = new HashSet<OrderDetail>();
        }

        public int OrderId { get; set; }
        public string CustomerId { get; set; }
        public int? EmployeeId { get; set; }
        public DateTime? OrderDate { get; set; }
        public DateTime? RequiredDate { get; set; }
        public DateTime? ShippedDate { get; set; }
        public int? ShipVia { get; set; }
        public decimal? Freight { get; set; }
        public string ShipName { get; set; }
        public string ShipAddress { get; set; }
        public string ShipCity { get; set; }
        public string ShipRegion { get; set; }
        public string ShipPostalCode { get; set; }
        public string ShipCountry { get; set; }

        public virtual Customer Customer { get; set; }
        public virtual Shipper ShipViaNavigation { get; set; }
        public virtual ICollection<OrderDetail> OrderDetails { get; set; }
    }
}

NorthwindContext

using Microsoft.EntityFrameworkCore;
#nullable disable

namespace Grid.Northwind {
    public partial class NorthwindContext : DbContext {

        public NorthwindContext(DbContextOptions<NorthwindContext> options)
            : base(options) {
        }
        // ...
        public virtual DbSet<Order> Orders { get; set; }
        // ...

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder) {
            if(!optionsBuilder.IsConfigured) {
                optionsBuilder.UseSqlServer("Server=.\\sqlexpress;Database=Northwind;Integrated Security=true");
            }
        }

        protected override void OnModelCreating(ModelBuilder modelBuilder) {
            modelBuilder.HasAnnotation("Relational:Collation", "SQL_Latin1_General_CP1_CI_AS");
            // ...
            modelBuilder.Entity<Order>(entity => {
                entity.HasIndex(e => e.CustomerId, "CustomerID");
                entity.HasIndex(e => e.CustomerId, "CustomersOrders");
                entity.HasIndex(e => e.EmployeeId, "EmployeeID");
                entity.HasIndex(e => e.EmployeeId, "EmployeesOrders");
                entity.HasIndex(e => e.OrderDate, "OrderDate");
                entity.HasIndex(e => e.ShipPostalCode, "ShipPostalCode");
                entity.HasIndex(e => e.ShippedDate, "ShippedDate");
                entity.HasIndex(e => e.ShipVia, "ShippersOrders");
                entity.Property(e => e.OrderId).HasColumnName("OrderID");
                entity.Property(e => e.CustomerId)
                    .HasMaxLength(5)
                    .HasColumnName("CustomerID")
                    .IsFixedLength(true);
                entity.Property(e => e.EmployeeId).HasColumnName("EmployeeID");
                entity.Property(e => e.Freight)
                    .HasColumnType("money")
                    .HasDefaultValueSql("((0))");
                entity.Property(e => e.OrderDate).HasColumnType("datetime");
                entity.Property(e => e.RequiredDate).HasColumnType("datetime");
                entity.Property(e => e.ShipAddress).HasMaxLength(60);
                entity.Property(e => e.ShipCity).HasMaxLength(15);
                entity.Property(e => e.ShipCountry).HasMaxLength(15);
                entity.Property(e => e.ShipName).HasMaxLength(40);
                entity.Property(e => e.ShipPostalCode).HasMaxLength(10);
                entity.Property(e => e.ShipRegion).HasMaxLength(15);
                entity.Property(e => e.ShippedDate).HasColumnType("datetime");
                entity.HasOne(d => d.Customer)
                    .WithMany(p => p.Orders)
                    .HasForeignKey(d => d.CustomerId)
                    .HasConstraintName("FK_Orders_Customers");
                entity.HasOne(d => d.ShipViaNavigation)
                    .WithMany(p => p.Orders)
                    .HasForeignKey(d => d.ShipVia)
                    .HasConstraintName("FK_Orders_Shippers");
            });
            // ...
            OnModelCreatingPartial(modelBuilder);
        }

        partial void OnModelCreatingPartial(ModelBuilder modelBuilder);
    }
}

Program.cs

using Microsoft.EntityFrameworkCore;
// ...
builder.Services.AddDbContextFactory<NorthwindContext>((sp, options) => {
    var env = sp.GetRequiredService<IWebHostEnvironment>();
    var dbPath = Path.Combine(env.ContentRootPath, "Northwind-5e44b51f.mdf");
    options.UseSqlServer("Server=(localdb)\\MSSQLLocalDB;Integrated Security=true;AttachDbFileName=" + dbPath);
});

For more information about paging in the Grid component, refer to the following topic: Paging in Blazor Grid.