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DxTreeList.ClearSelection() Method
Namespace : DevExpress.Blazor
Assembly :
DevExpress.Blazor.v24.2.dll
NuGet Package :
DevExpress.Blazor
# Declaration
C#
public void ClearSelection ( )
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:
@inject EmployeeTaskService EmployeeTaskService
<style >
.my-button {
width: 200px;
}
</style >
<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 >
<br />
<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();
}
}
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 ; }
}
}
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 ) ;
}
}
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 selection in the TreeList component, refer to the following topic: Selection and Focus in Blazor TreeList .
See Also