Hi Prasanthan,
Thanks for contacting Syncfusion support.
We can bind the Treestructured data to the Dropdownlist control with the checkboxes using ContentTemplate API. Using ContentTemplate we can define the customized structure for the content of the Dropdownlist control as shown in the following code snippet.
<code>
<ej:DropDownList ID="selectFolder" runat="server" ClientIDMode="Static" Width="280px" PopupWidth="280px" PopupHeight="280px" WatermarkText="Select any value">
<Items>
<ej:DropDownListItem>
<ContentTemplate>
<ej:TreeView ID="Treeview" runat="server" DataTextField="Text" ClientIDMode="Static" DataIdField="ID" DataParentIdField="ParentID"
DataHasChildField="HasChild" ClientSideOnNodeExpanded="checkScroll" ClientSideOnNodeChecked="onNodeCheck" ClientSideOnNodeUnchecked="onNodeUnCheck" ClientSideOnNodeSelected="onNodeSelect" ShowCheckbox="true" ClientSideOnNodeCollapsed="checkScroll">
</ej:TreeView>
</ContentTemplate>
</ej:DropDownListItem>
</Items>
</ej:DropDownList>
</code>
We have prepared the simple sample Dropdownlist with Treeview along with checkbox enabled and the same can be downloaded from the following location.
Sample Location: Sample
Regards,
Saranya.S