DxGrid.GetDataItemValue(Object, String) Method

Returns the value of the specified field for the specified data item.

Namespace: DevExpress.Blazor

Assembly: DevExpress.Blazor.v23.1.dll

NuGet Package: DevExpress.Blazor

Declaration

public object GetDataItemValue(
    object dataItem,
    string fieldName
)

Parameters

Name	Type	Description
dataItem	Object	The data item whose field value should be returned.
fieldName	String	The name of the data field whose value should be returned.

Returns

Type	Description
Object	The field value.

Remarks

Call the GetDataItemValue method when the Grid is bound to one of the following data sources:

• An Instant Feedback Data Source whose AreSourceRowsThreadSafe option is set to false (the default value)
• A collection of anonymous objects

In other cases, you can cast a data item to a required type and use the {DataItem.FieldName} notation instead. You can also call the GetRowValue(Int32, String) method to get a field value for a data row with the specified visible index.

The following example uses the EntityInstantFeedbackSource and calls the GetDataItemValue method to get the selected data item’s ProductName:

Razor

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

<DxGrid Data="InstantFeedbackSource"
        AllowSelectRowByClick="true"
        SelectionMode="GridSelectionMode.Single"
        @bind-SelectedDataItem="@SelectedDataItem"
        KeyFieldName="ProductId"
        @ref="MyGrid">
    <Columns>
        <DxGridSelectionColumn />
        <DxGridDataColumn FieldName="ProductName" />
        <DxGridDataColumn FieldName="UnitPrice" />
    </Columns>
</DxGrid>

<div style="margin-top: 10px">
    <DxButton Click="OnGetSelectedProductName">Get Selected Product Name</DxButton>
</div>
<div style="margin-top: 10px">
    Selected Product Name: @SelectedProductInfo
</div>

@code {
    EntityInstantFeedbackSource InstantFeedbackSource { get; set; }
    NorthwindContext Northwind { get; set; }
    object SelectedDataItem { get; set; }
    IGrid MyGrid { get; set; }
    string SelectedProductInfo { get; set; }

    protected override void OnInitialized() {
        Northwind = NorthwindContextFactory.CreateDbContext();
        InstantFeedbackSource = new EntityInstantFeedbackSource(e => {
            e.KeyExpression = "ProductId";
            e.QueryableSource = Northwind.Products;
        });
    }

    void OnGetSelectedProductName() {
        SelectedProductInfo = (string)MyGrid.GetDataItemValue(SelectedDataItem, "ProductName");
    }

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

Product

using System;
using System.Collections.Generic;

#nullable disable

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

        public int ProductId { get; set; }
        public string ProductName { get; set; }
        public int? SupplierId { get; set; }
        public int? CategoryId { get; set; }
        public string QuantityPerUnit { get; set; }
        public decimal? UnitPrice { get; set; }
        public short? UnitsInStock { get; set; }
        public short? UnitsOnOrder { get; set; }
        public short? ReorderLevel { get; set; }
        public bool Discontinued { get; set; }

        public virtual Category Category { get; set; }
        public virtual Supplier Supplier { 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<Product> Products { 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<Product>(entity => {
                entity.HasIndex(e => e.CategoryId, "CategoriesProducts");
                entity.HasIndex(e => e.CategoryId, "CategoryID");
                entity.HasIndex(e => e.ProductName, "ProductName");
                entity.HasIndex(e => e.SupplierId, "SupplierID");
                entity.HasIndex(e => e.SupplierId, "SuppliersProducts");
                entity.Property(e => e.ProductId).HasColumnName("ProductID");
                entity.Property(e => e.CategoryId).HasColumnName("CategoryID");
                entity.Property(e => e.ProductName)
                    .IsRequired()
                    .HasMaxLength(40);
                entity.Property(e => e.QuantityPerUnit).HasMaxLength(20);
                entity.Property(e => e.ReorderLevel).HasDefaultValueSql("((0))");
                entity.Property(e => e.SupplierId).HasColumnName("SupplierID");
                entity.Property(e => e.UnitPrice)
                    .HasColumnType("money")
                    .HasDefaultValueSql("((0))");
                entity.Property(e => e.UnitsInStock).HasDefaultValueSql("((0))");
                entity.Property(e => e.UnitsOnOrder).HasDefaultValueSql("((0))");
                entity.HasOne(d => d.Category)
                    .WithMany(p => p.Products)
                    .HasForeignKey(d => d.CategoryId)
                    .HasConstraintName("FK_Products_Categories");
                entity.HasOne(d => d.Supplier)
                    .WithMany(p => p.Products)
                    .HasForeignKey(d => d.SupplierId)
                    .HasConstraintName("FK_Products_Suppliers");
            });
            // ...
            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

GetDataItemValue(Object, String)