DxGrid.CustomizeSummaryDisplayText Event

Allows you to customize the summary display text.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v21.2.dll

NuGet Package: DevExpress.Blazor

Declaration

[Parameter]
public Action<GridCustomizeSummaryDisplayTextEventArgs> CustomizeSummaryDisplayText { get; set; }

Parameters

Type	Description
GridCustomizeSummaryDisplayTextEventArgs	A GridCustomizeSummaryDisplayTextEventArgs object that contains data for this event.

Remarks

Use GridCustomizeSummaryDisplayTextEventArgs (Value, DisplayText, and so on) to specify the summary display text and access other grid data.

The example below illustrates how to create a custom summary item, whose value is evaluated and formatted within the CustomSummary and CustomizeSummaryDisplayText event handlers.

Razor

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

<DxGrid Data="GridDataSource"
        UnboundColumnData="Grid_CustomUnboundColumnData"
        CustomizeSummaryDisplayText="Grid_CustomizeSummaryDisplayText"
        CustomSummary="Grid_CustomSummary"
        AllowSelectRowByClick="true"
        SelectedDataItems="@SelectedDataItems"
        SelectedDataItemsChanged="Grid_SelectedDataItemsChanged"
        @ref="Grid">
    <Columns>
        <DxGridSelectionColumn />
        <DxGridDataColumn FieldName="ProductId" Caption="Product ID" DisplayFormat="d" />
        <DxGridDataColumn FieldName="UnitPrice" />
        <DxGridDataColumn FieldName="Quantity" />
        <DxGridDataColumn FieldName="Discount" DisplayFormat="p0" />
        <DxGridDataColumn FieldName="TotalPrice"
                          DisplayFormat="c"
                          UnboundType="GridUnboundColumnType.Decimal" />
    </Columns>
    <TotalSummary>
        <DxGridSummaryItem SummaryType="GridSummaryItemType.Custom" Name="Custom" FieldName="TotalPrice" />
    </TotalSummary>
</DxGrid>

@code {
    IEnumerable<object> GridDataSource { get; set; }
    NorthwindContext Northwind { get; set; }
    IReadOnlyList<object> SelectedDataItems { get; set; }
    IGrid Grid { get; set; }

    protected override void OnInitialized() {
        Northwind = NorthwindContextFactory.CreateDbContext();
        GridDataSource = Northwind.OrderDetails
            .Include(i => i.Order)
            .Include(i => i.Product)
            .ToList();
        SelectedDataItems = GridDataSource.Skip(1).Take(2).ToList();
    }

    void Grid_CustomSummary(GridCustomSummaryEventArgs e) {
        switch (e.SummaryStage) {
            case GridCustomSummaryStage.Start:
                e.TotalValue = 0m;
                break;
            case GridCustomSummaryStage.Calculate:
                if (e.Grid.IsDataItemSelected(e.DataItem))
                    e.TotalValue = (decimal)e.TotalValue + (decimal)e.GetRowValue("TotalPrice");
                break;
            case GridCustomSummaryStage.Finalize:
                e.TotalValueReady = true;
                break;
        }
    }

    void Grid_CustomizeSummaryDisplayText(GridCustomizeSummaryDisplayTextEventArgs e) {
        if (e.Item.Name == "Custom")
            e.DisplayText = string.Format("Sum of Selected: {0:c}", e.Value);
    }

    void Grid_CustomUnboundColumnData(GridUnboundColumnDataEventArgs e) {
        if (e.FieldName == "TotalPrice") {
            var UnitPrice = Convert.ToDecimal(e.GetRowValue("UnitPrice"));
            var Quantity = Convert.ToDecimal(e.GetRowValue("Quantity"));
            var Discount = Convert.ToDecimal(e.GetRowValue("Discount"));
            e.Value = Quantity * UnitPrice * (1 - Discount);
        }
    }

    void Grid_SelectedDataItemsChanged() {
        Grid.RefreshSummary();
    }

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

OrderDetail

using System;
using System.Collections.Generic;

#nullable disable

namespace Grid.Northwind {
    public partial class OrderDetail {
        public int OrderId { get; set; }
        public int ProductId { get; set; }
        public decimal UnitPrice { get; set; }
        public short Quantity { get; set; }
        public float Discount { get; set; }

        public virtual Order Order { get; set; }
        public virtual Product Product { 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<OrderDetail> OrderDetails { 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<OrderDetail>(entity => {
                entity.HasKey(e => new { e.OrderId, e.ProductId })
                    .HasName("PK_Order_Details");
                entity.ToTable("Order Details");
                entity.HasIndex(e => e.OrderId, "OrderID");
                entity.HasIndex(e => e.OrderId, "OrdersOrder_Details");
                entity.HasIndex(e => e.ProductId, "ProductID");
                entity.HasIndex(e => e.ProductId, "ProductsOrder_Details");
                entity.Property(e => e.OrderId).HasColumnName("OrderID");
                entity.Property(e => e.ProductId).HasColumnName("ProductID");
                entity.Property(e => e.Quantity).HasDefaultValueSql("((1))");
                entity.Property(e => e.UnitPrice).HasColumnType("money");
                entity.HasOne(d => d.Order)
                    .WithMany(p => p.OrderDetails)
                    .HasForeignKey(d => d.OrderId)
                    .OnDelete(DeleteBehavior.ClientSetNull)
                    .HasConstraintName("FK_Order_Details_Orders");
                entity.HasOne(d => d.Product)
                    .WithMany(p => p.OrderDetails)
                    .HasForeignKey(d => d.ProductId)
                    .OnDelete(DeleteBehavior.ClientSetNull)
                    .HasConstraintName("FK_Order_Details_Products");
            });
            // ...
            OnModelCreatingPartial(modelBuilder);
        }

        partial void OnModelCreatingPartial(ModelBuilder modelBuilder);
    }
}

Startup.cs (.NET 5.0)

using Microsoft.EntityFrameworkCore;
// ...
    public class Startup {
    // ...
        public void ConfigureServices(IServiceCollection services) {
        // ...
            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);
            });
        }
        // ...
    }

Program.cs (.NET 6.0)

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);
});

Run Demo: Grid - Custom Summary