TreeListExtension.BindToVirtualData(TreeListVirtualModeCreateChildrenMethod, TreeListVirtualModeNodeCreatingMethod) Method
Allows creation of treelist nodes on demand (virtual mode).
Namespace: DevExpress.Web.Mvc
Assembly: DevExpress.Web.Mvc5.v23.2.dll
NuGet Package: DevExpress.Web.Mvc5
Declaration
public TreeListExtension BindToVirtualData(
TreeListVirtualModeCreateChildrenMethod createChildrenMethod,
TreeListVirtualModeNodeCreatingMethod nodeCreatingMethod
)Parameters
| Name | Type | Description |
|---|---|---|
| createChildrenMethod | TreeListVirtualModeCreateChildrenMethod | A delegate method of the TreeListVirtualModeCreateChildrenMethod type that enables you to create a list of business objects that correspond to the child nodes owned by the processed node. |
| nodeCreatingMethod | TreeListVirtualModeNodeCreatingMethod | A delegate method of the TreeListVirtualModeNodeCreatingMethod type that enables you to specify the node’s key value and cell values. |
Returns
| Type | Description |
|---|---|
| TreeListExtension | A TreeListExtension object that is the TreeList. |
Remarks
In addition to bound and unbound modes, the TreeList extension can operate in Virtual Mode, which greatly reduces both the server load and start-up time when working with complex or dynamically created data. In virtual mode, a tree is created on demand. In this instance, child nodes are created and initialized when their parent node is expanded.
To implement a virtual mode for the TreeList extension, a specifically parameterized BindToVirtualData method can be used. The method’s parameters refer to delegate methods that can be declared as static methods within a model class. Within the first delegate method, create a list of business objects that correspond to the child nodes owned by the processed node. The second one enables you to specify the node’s key value and cell values.