DxTreeList.ClearSelection() Method

Clears selection.

Assembly : DevExpress.Blazor.v25.2.dll

Declaration

csharp

public void ClearSelection()

Remarks

TreeList rows can be selected in the following ways:

Users click rows, tap rows, or execute keyboard shortcuts to select rows. To enable this functionality, set the AllowSelectRowByClick property to true.
Users click checkboxes or radio buttons in the selection column. To display this column, declare a DxTreeListSelectionColumn object in the Columns template.
You call the Select* method. Refer to the TreeList’s member table for the list of available methods.

Call the ClearSelection method to clear selection of all rows on all pages, including rows hidden by a filter:

Razor
CSS
Product
NorthwindContext
Program.cs

razor

@inject EmployeeTaskService EmployeeTaskService

<DxTreeList @ref="MyTreeList"
            Data="TreeListData"
            KeyFieldName="Id"
            ParentKeyFieldName="ParentId"
            AllowSelectRowByClick="true"
            @bind-SelectedDataItems="@SelectedDataItems">
    <Columns>
        <DxTreeListDataColumn FieldName="Name" Caption="Task" />
        <DxTreeListDataColumn FieldName="EmployeeName" />
        <DxTreeListDataColumn FieldName="StartDate" />
        <DxTreeListDataColumn FieldName="DueDate" />
    </Columns>
</DxTreeList>


<DxButton Click="() => MyTreeList.ClearSelection()" CssClass="my-button" Text="Clear Selection" />

@code {
    List<EmployeeTask> TreeListData { get; set; }
    IReadOnlyList<object> SelectedDataItems { get; set; }
    ITreeList MyTreeList { get; set; }

    protected override void OnInitialized() {
        TreeListData = EmployeeTaskService.GenerateData();
        SelectedDataItems = TreeListData.Skip(1).Take(2).ToList();
    }
}

css

.my-button {
    width: 200px;
}

csharp

using System;
using System.Collections.Generic;

#nullable disable

namespace TreeList.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; }
    }
}

csharp

using Microsoft.EntityFrameworkCore;
#nullable disable

namespace TreeList.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);
    }
}

csharp

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 additional information about selection in the TreeList component, refer to the following topic: Selection and Focus in Blazor TreeList.

Implements

ClearSelection()