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Telerik.Web.UI.RadTreeView

Remarks

The RadTreeViewcontrol is used to display a list of nodes in a Web Forms page. The RadTreeViewcontrol supports the following features: bullet Danodeinding that allows the control to be populated from various datasources. Programmatic access to the RadTreeViewobject model which allows dynamic creation of treeviews, populating with nodes and customizing the behavior by various properties. Customizable appearance through built-in or user-defined skins. nodesThe RadTreeViewcontrol is made up of tree of nodes represented by Telerik.Web.UI.RadTreeNode objects. Nodes at the top level (level 0) are called root nodes. An node that has a parent node is called a child node. All root nodes are stored in the P:Telerik.Web.UI.RadTreeView.Nodes property of the RadTreeView control. Child nodes are stored in the P:Telerik.Web.UI.RadTreeNode.Nodes property of their parent Telerik.Web.UI.RadTreeNode . Each node has a P:Telerik.Web.UI.RadTreeNode.Text and a P:Telerik.Web.UI.RadTreeNode.Value property. The value of the P:Telerik.Web.UI.RadTreeNode.Text property is displayed in the RadTreeViewcontrol, while the P:Telerik.Web.UI.RadTreeNode.Value property is used to store any additional data about the node, such as data passed to the postback event associated with the node. When clicked, a node can navigate to another Web page indicated by the P:Telerik.Web.UI.RadTreeNode.NavigateUrl property.

Inheritance Hierarchy

  • System.Object
  • System.Web.UI.Control
  • System.Web.UI.WebControls.WebControl
  • System.Web.UI.WebControls.BaseDataBoundControl
  • System.Web.UI.WebControls.DataBoundControl
  • Telerik.Web.UI.RadDataBoundControl : IControl, IControlResolver, IFeatureGroup, IPostBackDataHandler, IScriptControl, ISkinnableControl
  • Telerik.Web.UI.ControlItemContainer : IControlItemContainer, INamingContainer, IXmlSerializable
  • Telerik.Web.UI.HierarchicalControlItemContainer
  • Telerik.Web.UI.RadTreeView : ICallbackEventHandler, IPostBackEventHandler, IRadTreeNodeContainer

Properties

AllowNodeEditing Boolean

Gets a value indicating whether the text of the tree nodes are edinodele in the browser.

Remarks

End-users can edit the text of tree-nodes by pressing F2 when the node is selected or by clicking on a node that is already selected (slow double click). You can disable / enable node editing for specific tree nodes by setting the AllowEdit property of the specific RadTreeNode.

                 After node editing, RadTreeView fires the NodeEdit
                 event and you can change the text of the node - the RadTreeNode instance is
                 contained in the NodeEdited property of the event arguments and the new text is
                 in the NewText property of the event arguments.

CausesValidation Boolean

Gets or sets a value indicating whether validation is performed when an item within the control is selected.

Remarks

By default, page validation is performed when an item is selected. Page validation determines whether the input controls associated with a validation control on the page all pass the validation rules specified by the validation control. You can specify or determine whether validation is performed on both the client and the server when an item is clicked by using the CausesValidation property. To prevent validation from being performed, set the CausesValidation property to false.

CheckBoxes Boolean

When set to true displays a checkbox next to each treenode.

CheckChildNodes RadTreeNodeCollection

Gets or sets a value indicating whether checking (unchecking) a node will check (uncheck) its child nodes.

CheckedNodes IList1`

Gets a collection of RadTreeNode objects that represent the nodes in the control that display a selected check box.

Remarks

When check boxes are displayed in the RadTreeView control (by setting the CheckBoxes property to true), use the CheckedNodes property to determine which nodes display a selected check box. This collection is commonly used to iterate through all the nodes that have a selected check box in the tree.

            The CheckedNodes collection is populated using a depth-first traversal of the tree
            structure: each parent node is processed down to its child nodes before the next
            parent node is populated.

ClientChanges IList1`

Gets a list of all client-side changes (adding a node, removing a node, changing a node's property) which have occurred.

Remarks

You can use the ClientChanges property to respond to client-side modifications such as adding a new itemremoving existing itemclearing the children of an item or the control itselfchanging a property of the item The ClientChanges property is available in the first postback (ajax) request after the client-side modifications have taken place. After this moment the property will return empty list.

ClientDataSourceID String

Gets or sets ID of ClientDataSource control that is used for client side binding

ClientIDMode ClientIDMode

This property is overridden in order to support controls which implement INamingContainer. The default value is changed to "AutoID".

ClientNodeTemplate ITemplate

Gets or sets the HTML template of a when added on the client.

CollapseAnimation AnimationSettings

Gets the settings for the animation played when a node closes.

Remarks

Use the CollapseAnimation property to customize the expand animation of RadTreeView. You can specify the Type and Duration.

                To disable expand animation effects you should set the
                Type to
                AnimationType.None. To customize the expand animation you can
                use the ExpandAnimation property.

ContextMenus RadTreeViewContextMenuCollection

Gets a collection of RadTreeViewContextMenu objects that represent the context menus of a RadTreeView control.

Remarks

By default, if the ContextMenus collection contains RadTreeViewContextMenus, the first one is displayed on the right-click of each RadTreeNode. To disable a context menu for a RadTreeNode, set its EnableContextMenu property to false. To specify a different context menu for a RadTreeNode, use its ContextMenuID property.

CssClassFormatString String

The CssClass property will now be used instead of the former Skin and will be modified in AddAttributesToRender()

DataBindings RadTreeNodeBindingCollection

Gets a collection of objects that define the relationship between a data item and the tree node it is binding to.

EnableAjaxSkinRendering String

Gets or sets the value, indicating whether to render the skin CSS files during Ajax requests

Remarks

If EnableAjaxSkinRendering is set to false you will have to register the needed control base CSS file by hand when adding/showing the control with Ajax.

EnableAriaSupport Boolean

When set to true enables support for WAI-ARIA

EnableDragAndDrop Boolean

When set to true enables drag-and-drop functionality

EnableDragAndDropBetweenNodes RadTreeNodeCollection

When set to true enables drag-and-drop visual clue (underline) between nodes while draggin

EnableEmbeddedBaseStylesheet Boolean

Gets or sets the value, indicating whether to render the link to the embedded base stylesheet of the control or not.

Remarks

If EnableEmbeddedBaseStylesheet is set to false you will have to register the needed control base CSS file by hand.

EnableEmbeddedScripts Boolean

Gets or sets the value, indicating whether to render script references to the embedded scripts or not.

Remarks

If EnableEmbeddedScripts is set to false you will have to register the needed Scripts files by hand.

EnableEmbeddedSkins String

Gets or sets the value, indicating whether to render links to the embedded skins or not.

Remarks

If EnableEmbeddedSkins is set to false you will have to register the needed CSS files by hand.

EnableNodeTextHtmlEncoding Boolean

Gets or sets a value indicating whether RadTreeView should HTML encode the text of the nodes.

EnableRippleEffect Boolean

Returns true if ripple effect should be added

ExpandAnimation AnimationSettings

Gets the settings for the animation played when a node opens.

Remarks

Use the ExpandAnimation property to customize the expand animation of RadTreeView. You can specify the Type and Duration. To disable expand animation effects you should set the Type to AnimationType.None. To customize the collapse animation you can use the CollapseAnimation property.

IsEmpty Boolean

Gets a value indicating whether the RadTreeView control has no nodes.

IsSkinSet String

For internal use.

KeyboardNavigationSettings KeyboardNavigationSettings

Used to customize the keyboard navigation functionality.

LoadingMessage String

Gets or sets the loading message that is displayed when child nodes are retrieved on AJAX calls.

Remarks

This property can be used for localization purposes (e.g. "Loading..." in different languages).

LoadingStatusPosition TreeViewLoadingStatusPosition

Gets or sets the position of the loading message when child nodes are retrieved on AJAX calls.

LoadingStatusTemplate ITemplate

Gets or sets the loading status template.

MaxDataBindDepth Int32

Gets or sets the maximum number of levels to bind to the RadTreeView control.

Remarks

When binding the RadTreeView control to a data source, use the MaxDanodeindDepth property to limit the number of levels to bind to the control. For example, setting this property to 2 binds only the root nodes and their immediate children. All remaining records in the data source are ignored.

MultipleSelect Boolean

When set to true the treeview allows multiple node selection (by holding down ctrl key while selecting nodes)

Nodes RadTreeNodeCollection

Gets a object that contains the root nodes of the current RadTreeView control.

Remarks

Use the nodes property to access the root nodes of the RadTreeView control. You can also use the nodes property to manage the root nodes - you can add, remove or modify nodes.

NodeTemplate ITemplate

Gets or sets the template for displaying all node in the current RadTreeView.

ODataDataSourceID String

Gets or sets the ODataDataSource used for data binding.

OnClientContextMenuItemClicked String

The name of the JavaScript function that will be called after the user clicks on a context menu item.

OnClientContextMenuItemClicking String

The name of the JavaScript function that will be called when the user clicks on a context menu item.

OnClientContextMenuShowing String

The name of the JavaScript function that will be called when a context menu is to be displayed.

OnClientContextMenuShown String

The name of the JavaScript function that will be called after context menu is displayed.

OnClientDoubleClick String

The name of the JavaScript function that will be called when the user double clicks on a node.

OnClientKeyPressing String

The name of the JavaScript function that will be called when a key is pressed.

OnClientLoad String

Gets or sets the name of the JavaScript function called when the control is fully initialized on the client side.

OnClientMouseOut String

The name of the JavaScript function that will be called when the mouse hovers away from the TreeView.

OnClientMouseOver String

The name of the JavaScript function that will be called when the user highlights a treenode.

OnClientNodeAnimationEnd String

Gets or sets the name of the JavaScript function called when a node's expand/collapse animation finishes

OnClientNodeChecked String

The name of the JavaScript function that will be called after the user checks (checkbox) a treenode.

OnClientNodeChecking String

The name of the JavaScript function that will be called when the user checks (checkbox) a treenode.

OnClientNodeClicked String

The name of the JavaScript function that will be called after click on a treenode. Used for AJAX/callback hooks.

OnClientNodeClicking String

The name of the JavaScript function that will be called upon click on a treenode. The function must accept a single parameter which is the instance of the node clicked. For example if you define OnClientClick="ProcessClientClick", you must define a javascript function defined in the following way (example): function ProcessClientClick(node) { alert("You clicked on: " + node.Text); }

OnClientNodeCollapsed String

The name of the JavaScript function that will be called after a node is collapsed.

OnClientNodeCollapsing String

The name of the JavaScript function that will be called before a node is collapsed.

OnClientNodeDataBound String

Gets or sets the name of the JavaScript function called when a node is databound during load on demand

OnClientNodeDragging String

The name of the JavaScript function that will be called when the user moves the mouse while dragging a node.

OnClientNodeDragStart String

The name of the JavaScript function that will be called when the user starts dragging a node.

OnClientNodeDropped String

The name of the JavaScript function that will be called after the user drops a node onto another node.

OnClientNodeDropping String

The name of the JavaScript function that will be called when the user drops a node onto another node.

OnClientNodeEdited String

The name of the JavaScript function that will be called after the user edits a node

OnClientNodeEditing String

The name of the JavaScript function that will be called before the user edits a node

OnClientNodeEditStart String

Gets or sets the name of the JavaScript function called when a node starts being edited

OnClientNodeExpanded String

The name of the JavaScript function that will be called after a node is expanded.

OnClientNodeExpanding String

The name of the JavaScript function that will be called before a node is expanded.

OnClientNodePopulated String

Gets or sets a value indicating the client-side event handler that is called when the children of a tree node were just populated (for example from web service).

Remarks

If specified, the OnClientNodePopulated client-side event handler is called when the children of a tree node were just populated. Two parameters are passed to the handler:sender, the menu client object;eventArgs with one property: get_node(), the instance of the tree node.This event cannot be cancelled.

OnClientNodePopulating String

Gets or sets a value indicating the client-side event handler that is called when the children of a tree node are about to be populated (for example from web service).

Remarks

If specified, the OnClientNodePopulating client-side event handler is called when the children of a tree node are about to be populated. Two parameters are passed to the handler:sender, the menu client object;eventArgs with three properties: get_node(), the instance of the node.get_context(), an user object that will be passed to the web service.set_cancel(), used to cancel the event.This event can be cancelled.

OnClientNodePopulationFailed String

Gets or sets a value indicating the client-side event handler that is called when the operation for populating the children of a tree node has failed.

Remarks

If specified, the OnClientNodePopulationFailed client-side event handler is called when the operation to populate the children of a tree node has failed. Two parameters are passed to the handler:sender, the menu client object;eventArgs with three properties: get_node(), the instance of the tree node.set_cancel(), set to true to suppress the default action (alert message).This event cannot be cancelled.

OnClientTemplateDataBound String

Gets or sets the name of the JavaScript function called when the client template for a node is evaluated

OnClientTreePopulated String

Gets or sets the OnClientTreePopulated event value in the ViewState.

OnClientTreePopulating String

Gets or sets the OnClientTreePopulating event value in the ViewState.

PersistLoadOnDemandNodes RadTreeNodeCollection

When set to true, the nodes populated through Load On Demand are persisted on the server.

PostBackUrl String

Gets or sets the URL of the page to post to from the current page when a tree node is clicked.

PostBackUrl String

Gets or sets the URL of the page to post to from the current page when a tab from the tabstrip is clicked.

RegisterWithScriptManager Boolean

Gets or sets the value, indicating whether to register with the ScriptManager control on the page.

Remarks

If RegisterWithScriptManager is set to false the control can be rendered on the page using Web Services or normal callback requests/page methods.

RenderMode RenderMode

Specifies the rendering mode of the control. Setting the mode to Lightweight will yield HTML 5/CSS 3 html and css. If the set value is Auto use ResolvedRenderMode to receive the actual RenderMode with respect to the user angent of the current request.

Remarks

Lightweight rendering mode might change the outlook of the component in some older browsers that don't support CSS3/HTML5.

ResolvedRenderMode RenderMode

Returns resolved RenderMode should the original value was Auto

RuntimeSkin String

Gets the real skin name for the control user interface. If Skin is not set, returns "Default", otherwise returns Skin.

SelectedNode RadTreeNode

Gets a RadTreeNode object that represents the selected node in the RadTreeView control.

Remarks

When a node is in selection mode, the user can select a node by clicking on the text in the node. Use the SelectedNode property to determine which node is selected in the TreeView control. A node cannot be selected when the TreeView control displays hyperlinks. When hyperlinks are displayed, the SelectedNode property always returns a null reference (Nothing in Visual Basic). When the user selects a different node in the RadTreeView control by clicking the text in the new node, the NodeClick event is raised, by default. If you set the MultipleSelect property of the treeview to true, end-users can select multiple nodes by holding the Ctrl / Shift keys while selecting.

SelectedNodes IList1`

Gets a collection of RadTreeNode objects that represent the nodes in the control that are currently selected.

Remarks

This collection is commonly used to iterate through all the nodes that have been selected in the tree.The SelectedNodes collection is populated using a depth-first traversal of the tree structure: each parent node is processed down to its child nodes before the next parent node is populated.

SelectedValue String

Gets the Value of the selected node.

ShowLineImages Boolean

Gets a value indicating whether the dotted lines indenting the nodes should be displayed or not.

SingleExpandPath Boolean

Gets a value indicating whether only the current branch of the treeview is expanded.

Remarks

The property closes all nodes that are not parents of the last expanded node. This property is only effective on the client browser - in postback modes you need to handle the logic yourself.

Skin String

Gets or sets the skin name for the control user interface.

Remarks

If this property is not set, the control will render using the skin named "Default". If EnableEmbeddedSkins is set to false, the control will not render skin.

SupportsDisabledAttribute Boolean

For internal use.

TriStateCheckBoxes Boolean

Gets or sets a value indicating whether RadTreeView should display tri-state checkboxes.

Remarks

Enabling three state checkbox support requires the property to be set to true.

UniqueID String

Gets the unique, hierarchically qualified identifier for the server control.

ValidationGroup String

Gets or sets the name of the validation group to which this validation control belongs.

Remarks

This property works only when CausesValidation is set to true.

WebServiceSettings NavigationControlWebServiceSettings

Gets the settings for the web service used to populate nodes when ExpandMode set to TreeNodeExpandMode.WebService.

Remarks

Use the WebServiceSettings property to configure the web service used to populate nodes on demand. You must specify both Path and Method to fully describe the service.

                    You can use the LoadingStatusTemplate
                    property to create a loading template.

                    In order to use the integrated support, the web service should have the following signature:


                    [ScriptService]
                    public class WebServiceName : WebService
                    {
                        [WebMethod]
                        public RadTreeNodeData[] WebServiceMethodName(RadTreeNodeData item, object context)
                        {
                            // We cannot use a dictionary as a parameter, because it is only supported by script services.
                            // The context object should be cast to a dictionary at runtime.
                            IDictionary<string, object> contextDictionary = (IDictionary<string, object>) context;

                            //...
                        }
                    }

Methods

AddProperty

Adds the property to the IScriptDescriptor, if it's value is different from the given default.

Parameters

descriptor Telerik.Web.UI.IScriptDescriptor

The descriptor to add the property to.

name System.String

The property name.

value System.Object

The current value of the property.

defaultValue System.Object

The default value.

Returns

System.Void

ApplyConditionalRendering

Use this from RenderContents of the inheritor

Returns

System.Void

CheckAllNodes

Checks all nodes of the current RadTreeView object.

Returns

System.Void

CollapseAllNodes

Collapses all nodes in the tree.

Returns

System.Void

ControlPreRender

Code moved into this method from OnPreRender to make sure it executed when the framework skips OnPreRender() for some reason

Returns

System.Void

DescribeRenderingMode

Should be used by inheritors

Returns

System.Void

ExpandAllNodes

Expands all nodes in the tree.

Returns

System.Void

FindNode

Returns the first RadTreeNode that matches the conditions defined by the specified predicate. The predicate should returns a boolean value.

Parameters

match System.Predicate{Telerik.Web.UI.RadTreeNode}

The Predicate <> that defines the conditions of the element to search for.

Returns

Telerik.Web.UI.RadTreeNode

FindNodeByAttribute

Searches all nodes for a RadTreeNode which contains the specified attribute and attribute value.

Parameters

attributeName System.String

The name of the target attribute.

attributeValue System.String

The value of the target attribute

Returns

Telerik.Web.UI.RadTreeNode The RadTreeNode that matches the specified arguments. Null (Nothing) is returned if no node is found.

FindNodeByText

Searches all nodes for a RadTreeNode with a Text property equal to the specified text.

Parameters

text System.String

The text to search for

Returns

Telerik.Web.UI.RadTreeNode A RadTreeNode whose Text property equals to the specified argument. Null (Nothing) is returned when no matching node is found.

FindNodeByText

Searches all nodes for a RadTreeNode with a Text property equal to the specified text.

Parameters

text System.String

The text to search for

ignoreCase System.Boolean

A Boolean indicating a case-sensitive or insensitive comparison (true indicates a case-insensitive comparison).

Returns

Telerik.Web.UI.RadTreeNode A RadTreeNode whose Text property equals to the specified argument. Null (Nothing) is returned when no matching node is found.

FindNodeByUrl

Searches all nodes for a RadTreeNode with a NavigateUrl property equal to the specified URL.

Remarks

The ResolveUrl method is used to resolve NavigateUrl property before comparing it to the specified URL.

Parameters

url System.String

The URL to search for

Returns

Telerik.Web.UI.RadTreeNode A RadTreeNode whose NavigateUrl property equals to the specified argument. Null (Nothing) is returned when no matching node is found.

FindNodeByValue

Searches all nodes for a RadTreeNode with a Value property equal to the specified value.

Parameters

value System.String

The value to search for

Returns

Telerik.Web.UI.RadTreeNode A RadTreeNode whose Value property equals to the specified argument. Null (Nothing) is returned when no matching node is found.

FindNodeByValue

Searches all nodes for a RadTreeNode with a Value property equal to the specified value.

Parameters

value System.String

The value to search for

ignoreCase System.Boolean

A Boolean indicating a case-sensitive or insensitive comparison (true indicates a case-insensitive comparison).

Returns

Telerik.Web.UI.RadTreeNode A RadTreeNode whose Value property equals to the specified argument. Null (Nothing) is returned when no matching node is found.

GetAllNodes

Gets a linear list of all nodes in the RadTreeView control.

Returns

System.Collections.Generic.IList1` An IList containing all nodes (from all hierarchy levels).

GetEmbeddedSkinNames

Returns the names of all embedded skins. Used by Telerik.Web.Examples.

Returns

System.Collections.Generic.List1`

GetXml

Gets an XML string representing the state of the control. All child items and their properties are serialized in this string.

Remarks

Use the GetXml method to get the XML state of the control. You can cache it and then restore it using the LoadXml method.

Returns

System.String A String representing the state of the control - child items, properties etc.

LoadClientState

Loads the client state data

Parameters

clientState System.Collections.Generic.Dictionary{System.String,System.Object}

Returns

System.Void

LoadContentFile

Populates the control from the specified XML file.

Parameters

fileName System.String

The name of the XML file.

Returns

System.Void

LoadPostData

Executed when post data is loaded from the request

Parameters

postDataKey System.String

postCollection System.Collections.Specialized.NameValueCollection

Returns

System.Boolean

LoadXml

Loads the control from an XML string.

Remarks

Use the LoadXml method to populate the control from an XML string. You can use it along the GetXml method to implement caching.

Parameters

xml System.String

The string representing the XML from which the control will be populated.

Returns

System.Void

LoadXmlString

Loads the control from an XML string. Identical to LoadXml.

Parameters

xml System.String

The XML string to populate from.

Returns

System.Void

RaisePostDataChangedEvent

Executed when post data changes should invoke a changed event

Returns

System.Void

RegisterCssReferences

Registers the CSS references

Returns

System.Void

RegisterScriptControl

Registers the control with the ScriptManager

Returns

System.Void

SaveClientState

Saves the client state data

Returns

System.String

UncheckAllNodes

This method unchecks all nodes of the current RadTreeView instance. Useful when you need to uncheck all nodes after postback.

Returns

System.Void

UnselectAllNodes

This method unselects all nodes of the current RadTreeView instance. Useful when you need to clear node selection after postback.

Returns

System.Void

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