ASP.NET MVC DropDownTree Overview

The Telerik UI DropDownTree HtmlHelper for ASP.NET MVC is a server-side wrapper for the Kendo UI DropDownTree widget.

The DropDownTree represents an editor of hierarchical data, rendered in a tree-like structure, which provides multiple selection option and custom nodes.

• Demo page for the DropDownTree HtmlHelper

Initializing the DropDownTree

The following example demonstrates how to define the DropDownTree.

Razor

@(Html.Kendo().DropDownTree()
    .Name("dropdowntree")
    .DataTextField("Name")
    .DataValueField("id")
    .DataSource(dataSource => dataSource
        .Read(read => read
            .Action("Read_DropDownTreeData", "Home")
        )
    )
)

C#

public static IList<HierarchicalViewModel> GetHierarchicalData()
{
    var result = new List<HierarchicalViewModel>()
    {
        new HierarchicalViewModel() { ID = 1, ParentID = null, HasChildren = true, Name = "Parent item" },
        new HierarchicalViewModel() { ID = 2, ParentID = 1, HasChildren = true, Name = "Parent item" },
        new HierarchicalViewModel() { ID = 3, ParentID = 1, HasChildren = false, Name = "Item" },
        new HierarchicalViewModel() { ID = 4, ParentID = 2, HasChildren = false, Name = "Item" },
        new HierarchicalViewModel() { ID = 5, ParentID = 2, HasChildren = false, Name = "Item" }
    };

    return result;
}

public ActionResult Read_DropDownTreeData(int? id)
{
    var result = GetHierarchicalData()
        .Where(x => id.HasValue ? x.ParentID == id : x.ParentID == null)
        .Select(item => new {
            id = item.ID,
            Name = item.Name,
            hasChildren = item.HasChildren
        });

    return Json(result, JsonRequestBehavior.AllowGet);
}

Basic Configuration

The following example demonstrates the basic configuration of the DropDownTree.

Razor

    @(Html.Kendo().DropDownTree()
        .Name("dropdowntree")
        .Checkboxes(true)
        .Filter(FilterType.Contains)
        .DataTextField("Name")
        .DataTextField("ID")
        .DataSource(dataSource => dataSource
            .Read(read => read
                .Action("Employees", "Home")
            )
        )
    )

Functionality and Features

Feature	Description
Data binding	The DropDownTree supports different data binding approaches.
Checkboxes	You can add checkboxes to the DropDownTree's items.
Filtering	You are able to filter the displayed DropDownTree items by their text value.
Items	You can configure different options for the items of the component.
Templates	The DropDownTree supports customizing its look through templates.
Accessibility	The DropDownTree is accessible by screen readers and provides WAI-ARIA, Section 508, WCAG 2.2, and keyboard support.

Next Steps

• Getting Started with the DropDownTree
• Basic Usage of the DropDownTree HtmlHelper for ASP.NET MVC (Demo)

See Also

• Using the API of the DropDownTree HtmlHelper for ASP.NET MVC (Demo)
• Knowledge Base Section