DxGrid.BeginUpdate() Method

Suspends Grid updates caused by parameter changes and method calls until the EndUpdate() method is called.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v24.2.dll

NuGet Package: DevExpress.Blazor

Declaration

public void BeginUpdate()

Remarks

You can use the BeginUpdate and EndUpdate() methods to complete the following tasks:

• Make multiple Grid modifications.
• Specify the Grid’s parameters outside the component’s markup.

Make Multiple Grid Modifications

The Grid is re-rendered after each modification that affects its appearance and/or functionality (for instance, if you change sort or group options in code).

When you make a sequence of modifications that cause the Grid to update, enclose your code between the BeginUpdate and EndUpdate method calls. The BeginUpdate method locks the Grid, while the EndUpdate method unlocks and redraws the Grid. This allows you to avoid excessive render operations and improve the Grid’s overall performance.

The following code snippet changes multiple sort options in the Grid:

Razor

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

<DxGrid Data="@Data" @ref="MyGrid">
    <Columns>
        <DxGridDataColumn FieldName="Country" SortIndex="0" />
        <DxGridDataColumn FieldName="City" SortIndex="1" />
        <DxGridDataColumn FieldName="OrderDate" />
        <DxGridDataColumn FieldName="UnitPrice" DisplayFormat="c" />
        <DxGridDataColumn FieldName="Quantity" />
    </Columns>
</DxGrid>
<br />

<DxButton Click="@(() => ChangeSortInfo())">Change Sort Options</DxButton>

@code {
    object Data { get; set; }
    NorthwindContext Northwind { get; set; }
    IGrid MyGrid { get; set; }

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

    void ChangeSortInfo() {
        MyGrid.BeginUpdate();
        MyGrid.ClearSort();
        MyGrid.SortBy("OrderDate");
        MyGrid.SortBy("UnitPrice", GridColumnSortOrder.Descending);
        MyGrid.EndUpdate();
    }

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

Invoice

using System;
#nullable disable

namespace Grid.Northwind {
    public partial class Invoice {
        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 string CustomerId { get; set; }
        public string CustomerName { get; set; }
        public string Address { get; set; }
        public string City { get; set; }
        public string Region { get; set; }
        public string PostalCode { get; set; }
        public string Country { get; set; }
        public string Salesperson { get; set; }
        public int OrderId { get; set; }
        public DateTime? OrderDate { get; set; }
        public DateTime? RequiredDate { get; set; }
        public DateTime? ShippedDate { get; set; }
        public string ShipperName { get; set; }
        public int ProductId { get; set; }
        public string ProductName { get; set; }
        public decimal UnitPrice { get; set; }
        public short Quantity { get; set; }
        public float Discount { get; set; }
        public decimal? ExtendedPrice { get; set; }
        public decimal? Freight { 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<Invoice> Invoices { 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.Entity<Invoice>(entity => {
                entity.HasNoKey();
                entity.ToView("Invoices");
                entity.Property(e => e.Address).HasMaxLength(60);
                entity.Property(e => e.City).HasMaxLength(15);
                entity.Property(e => e.Country).HasMaxLength(15);
                entity.Property(e => e.CustomerId)
                    .HasMaxLength(5)
                    .HasColumnName("CustomerID")
                    .IsFixedLength(true);
                entity.Property(e => e.CustomerName)
                    .IsRequired()
                    .HasMaxLength(40);
                entity.Property(e => e.ExtendedPrice).HasColumnType("money");
                entity.Property(e => e.Freight).HasColumnType("money");
                entity.Property(e => e.OrderDate).HasColumnType("datetime");
                entity.Property(e => e.OrderId).HasColumnName("OrderID");
                entity.Property(e => e.PostalCode).HasMaxLength(10);
                entity.Property(e => e.ProductId).HasColumnName("ProductID");
                entity.Property(e => e.ProductName)
                    .IsRequired()
                    .HasMaxLength(40);
                entity.Property(e => e.Region).HasMaxLength(15);
                entity.Property(e => e.RequiredDate).HasColumnType("datetime");
                entity.Property(e => e.Salesperson)
                    .IsRequired()
                    .HasMaxLength(31);
                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.Property(e => e.ShipperName)
                    .IsRequired()
                    .HasMaxLength(40);
                entity.Property(e => e.UnitPrice).HasColumnType("money");
            });
            // ...
            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);
});

Specify Grid Parameters

You can change values of the Grid’s parameters outside the component’s markup. To do this, enclose your code between the BeginUpdate and EndUpdate method calls. Otherwise, an exception occurs.

The following snippet changes the AllowSort parameter value to enable and disable data sorting:

Razor

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

<DxGrid Data="@Data" @ref="MyGrid">
    <Columns>
        <DxGridDataColumn FieldName="Country" />
        <DxGridDataColumn FieldName="City" />
        <DxGridDataColumn FieldName="OrderDate" />
        <DxGridDataColumn FieldName="UnitPrice" DisplayFormat="c" />
        <DxGridDataColumn FieldName="Quantity" />
    </Columns>
</DxGrid>
<br/>

<DxButton Click="@(() => SetAllowSort(false))">Disable Sorting</DxButton>
<DxButton Click="@(() => SetAllowSort(true))">Enable Sorting</DxButton>

@code {
    object Data { get; set; }
    NorthwindContext Northwind { get; set; }
    IGrid MyGrid { get; set; }

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

    void SetAllowSort (bool value) {
        MyGrid.BeginUpdate();
        MyGrid.AllowSort = value;
        MyGrid.EndUpdate();
    }

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

Invoice

using System;
#nullable disable

namespace Grid.Northwind {
    public partial class Invoice {
        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 string CustomerId { get; set; }
        public string CustomerName { get; set; }
        public string Address { get; set; }
        public string City { get; set; }
        public string Region { get; set; }
        public string PostalCode { get; set; }
        public string Country { get; set; }
        public string Salesperson { get; set; }
        public int OrderId { get; set; }
        public DateTime? OrderDate { get; set; }
        public DateTime? RequiredDate { get; set; }
        public DateTime? ShippedDate { get; set; }
        public string ShipperName { get; set; }
        public int ProductId { get; set; }
        public string ProductName { get; set; }
        public decimal UnitPrice { get; set; }
        public short Quantity { get; set; }
        public float Discount { get; set; }
        public decimal? ExtendedPrice { get; set; }
        public decimal? Freight { 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<Invoice> Invoices { 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.Entity<Invoice>(entity => {
                entity.HasNoKey();
                entity.ToView("Invoices");
                entity.Property(e => e.Address).HasMaxLength(60);
                entity.Property(e => e.City).HasMaxLength(15);
                entity.Property(e => e.Country).HasMaxLength(15);
                entity.Property(e => e.CustomerId)
                    .HasMaxLength(5)
                    .HasColumnName("CustomerID")
                    .IsFixedLength(true);
                entity.Property(e => e.CustomerName)
                    .IsRequired()
                    .HasMaxLength(40);
                entity.Property(e => e.ExtendedPrice).HasColumnType("money");
                entity.Property(e => e.Freight).HasColumnType("money");
                entity.Property(e => e.OrderDate).HasColumnType("datetime");
                entity.Property(e => e.OrderId).HasColumnName("OrderID");
                entity.Property(e => e.PostalCode).HasMaxLength(10);
                entity.Property(e => e.ProductId).HasColumnName("ProductID");
                entity.Property(e => e.ProductName)
                    .IsRequired()
                    .HasMaxLength(40);
                entity.Property(e => e.Region).HasMaxLength(15);
                entity.Property(e => e.RequiredDate).HasColumnType("datetime");
                entity.Property(e => e.Salesperson)
                    .IsRequired()
                    .HasMaxLength(31);
                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.Property(e => e.ShipperName)
                    .IsRequired()
                    .HasMaxLength(40);
                entity.Property(e => e.UnitPrice).HasColumnType("money");
            });
            // ...
            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);
});

Implements

BeginUpdate()