Class SfTreeView<TValue>

Specifies the TreeView component.

Inheritance

System.Object

Syncfusion.Blazor.SfBaseComponent

SfTreeView<TValue>

Namespace: Syncfusion.Blazor.Navigations

Assembly: Syncfusion.Blazor.dll

Syntax

public class SfTreeView<TValue> : SfBaseComponent, ITreeView

Type Parameters

Name	Description
TValue	"TValue parameter".

Constructors

SfTreeView()

Declaration

public SfTreeView()

Properties

AllowDragAndDrop

Indicates whether the TreeView allows drag and drop of nodes. To drag and drop a node in desktop, hold the mouse on the node, drag it to the target node and drop the node by releasing the mouse. For touch devices, drag and drop operation is performed by touch, touch move and touch end.

Declaration

public bool AllowDragAndDrop { get; set; }

Property Value

Type	Description
System.Boolean

AllowEditing

Enables or disables editing of the text in the TreeView node. When AllowEditing property is set to true, the TreeView allows you to edit the node by double clicking the node or by navigating to the node and pressing F2 key.

Declaration

public bool AllowEditing { get; set; }

Property Value

Type	Description
System.Boolean

AllowMultiSelection

Enables or disables multi-selection of nodes. To select multiple nodes: Select the nodes by holding down the CTRL key while clicking on the nodes. Select consecutive nodes by clicking the first node to select and hold down the SHIFT key and click the last node to select.

Declaration

public bool AllowMultiSelection { get; set; }

Property Value

Type	Description
System.Boolean

AllowTextWrap

Enables or disables to wrap the text in the TreeView node. When the AllowTextWrap property is set to true, the TreeView node text content will wrap to the next line when its text content exceeds the width of the TreeView node.

Declaration

public bool AllowTextWrap { get; set; }

Property Value

Type	Description
System.Boolean

Animation

Specifies the type of animation applied on expanding and collapsing the nodes along with duration.

Declaration

public TreeViewNodeAnimationSettings Animation { get; set; }

Property Value

Type	Description
TreeViewNodeAnimationSettings

AutoCheck

Allow us to specify the parent and child nodes to get auto check while we check or uncheck a node.

Declaration

public bool AutoCheck { get; set; }

Property Value

Type	Description
System.Boolean

CheckedNodes

The CheckedNodes property is used to set the nodes that need to be checked or get the ID of nodes that are currently checked in the TreeView component. The checkedNodes property depends upon the value of showCheckBox property.

Declaration

public string[] CheckedNodes { get; set; }

Property Value

Type	Description
System.String[]

CheckedNodesChanged

Specifies the callback to trigger when the checked nodes changes.

Declaration

public EventCallback<string[]> CheckedNodesChanged { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.String[]>

CssClass

Specifies the CSS classes to be added with root element of the TreeView to help customize the appearance of the component.

Declaration

public string CssClass { get; set; }

Property Value

Type	Description
System.String

Disabled

Specifies a value that indicates whether the TreeView component is disabled or not. When set to true, user interaction will not be occurred in TreeView.

Declaration

public bool Disabled { get; set; }

Property Value

Type	Description
System.Boolean

DropArea

Defines the area in which the draggable element movement will be occurring. Outside that area will be restricted for the draggable element movement. By default, the draggable element movement occurs in the entire page.

Declaration

public string DropArea { get; set; }

Property Value

Type	Description
System.String

EnableHtmlSanitizer

Defines whether to allow the cross-scripting site or not.

Declaration

public bool EnableHtmlSanitizer { get; set; }

Property Value

Type	Description
System.Boolean

EnablePersistence

Enables or disables persisting TreeView state between page reloads. If enabled, following APIs will persist.

1. SelectedNodes - Represents the nodes that are selected in the TreeView component.
2. checkedNodes - Represents the nodes that are checked in the TreeView component.
3. expandedNodes - Represents the nodes that are expanded in the TreeView component.

Declaration

public bool EnablePersistence { get; set; }

Property Value

Type	Description
System.Boolean

EnableRtl

Enable or disable rendering component in right to left direction.

Declaration

public bool EnableRtl { get; set; }

Property Value

Type	Description
System.Boolean

ExpandedNodes

Represents the expanded nodes in the TreeView component. We can set the nodes that need to be expanded or get the ID of the nodes that are currently expanded by using this property.

Declaration

public string[] ExpandedNodes { get; set; }

Property Value

Type	Description
System.String[]

ExpandedNodesChanged

Specifies the callback to trigger when the expanded nodes changes.

Declaration

public EventCallback<string[]> ExpandedNodesChanged { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.String[]>

ExpandOn

Specifies the action on which the node expands or collapses. The available actions are, Click - The expand/collapse operation happens when you single-click the node in both desktop and mobile devices. DblClick - The expand/collapse operation happens when you double-click the node in both desktop and mobile devices. None - The expand/collapse operation will not happen when you single-click or double-click the node in both desktop and mobile devices.

Declaration

public ExpandAction ExpandOn { get; set; }

Property Value

Type	Description
ExpandAction

Fields

Specifies the data source and mapping fields to render TreeView nodes.

Declaration

public TreeViewFieldsSettings<TValue> Fields { get; set; }

Property Value

Type	Description
TreeViewFieldsSettings<TValue>

FullRowNavigable

If this property is set to true, then the entire TreeView node will be navigate-able instead of text element.

Declaration

public bool FullRowNavigable { get; set; }

Property Value

Type	Description
System.Boolean

FullRowSelect

On enabling this property, the entire row of the TreeView node gets selected by clicking a node. When disabled only the corresponding node's text gets selected.

Declaration

public bool FullRowSelect { get; set; }

Property Value

Type	Description
System.Boolean

HtmlAttributes

Specify the HtmlAttributes for TreeView.

Declaration

public Dictionary<string, object> HtmlAttributes { get; set; }

Property Value

Type	Description
System.Collections.Generic.Dictionary<System.String, System.Object>

ID

Sets id attribute for the treeview element.

Declaration

public string ID { get; set; }

Property Value

Type	Description
System.String

LoadOnDemand

By default, the load on demand (Lazy load) is set to true. By disabling this property, all the tree nodes are rendered at the beginning itself.

Declaration

public bool LoadOnDemand { get; set; }

Property Value

Type	Description
System.Boolean

SelectedNodes

Represents the selected nodes in the TreeView component. We can set the nodes that need to be selected or get the ID of the nodes that are currently selected by using this property. On enabling AllowMultiSelection property we can select multiple nodes and on disabling it we can select only a single node.

Declaration

public string[] SelectedNodes { get; set; }

Property Value

Type	Description
System.String[]

SelectedNodesChanged

Specifies the callback to trigger when the selected nodes changes.

Declaration

public EventCallback<string[]> SelectedNodesChanged { get; set; }

Property Value

Type	Description
Microsoft.AspNetCore.Components.EventCallback<System.String[]>

ShowCheckBox

Indicates that the nodes will display CheckBoxes in the TreeView. The CheckBox will be displayed next to the expand/collapse icon of the node.

Declaration

public bool ShowCheckBox { get; set; }

Property Value

Type	Description
System.Boolean

SortOrder

Specifies a value that indicates whether the nodes are sorted in the ascending or descending order, or are not sorted at all. The available types of sort order are, None - The nodes are not sorted. Ascending - The nodes are sorted in the ascending order. Descending - The nodes are sorted in the ascending order.

Declaration

public SortOrder SortOrder { get; set; }

Property Value

Type	Description
SortOrder

TreeViewTemplates

Specifies the custom item template of TreeView Node item.

Declaration

public TreeViewTemplates<TValue> TreeViewTemplates { get; set; }

Property Value

Type	Description
TreeViewTemplates<TValue>

Methods

AddNodes(List<TValue>, String)

Adds the collection of TreeView nodes based on target and index position. If target node is not specified, then the nodes are added as children of the given parentID or in the root level of TreeView.

Declaration

public void AddNodes(List<TValue> nodes, string target = null)

Parameters

Type	Name	Description
System.Collections.Generic.List<TValue>	nodes	A list of nodes to be added to the TreeView.
System.String	target	Based on target nodes are added as children of the given parentID or in the root level of TreeView.

BuildRenderTree(RenderTreeBuilder)

Declaration

protected override void BuildRenderTree(RenderTreeBuilder __builder)

Parameters

Type	Name	Description
Microsoft.AspNetCore.Components.Rendering.RenderTreeBuilder	__builder

GetAllCheckedNodes()

Gets all the checked nodes including child, whether it is loaded or not.

Declaration

public List<string> GetAllCheckedNodes()

Returns

Type	Description
System.Collections.Generic.List<System.String>	"Task".

GetNode(String)

Get the node's data such as id, text, parentID, selected, isChecked, and expanded by passing the node element or it's ID.

Declaration

public NodeData GetNode(string node)

Parameters

Type	Name	Description
System.String	node	Specifies ID of TreeView node.

Returns

Type	Description
NodeData	"Return TreeData".

GetPropertyChanges()

Specifies the particular property is changes or not.

Declaration

protected IDictionary<string, object> GetPropertyChanges()

Returns

Type	Description
System.Collections.Generic.IDictionary<System.String, System.Object>	"Task".

GetRootElement()

Returns the route element reference of the component.

Declaration

public ElementReference GetRootElement()

Returns

Type	Description
Microsoft.AspNetCore.Components.ElementReference	"Task".

GetTreeData(String)

To get the updated data source of TreeView after performing some operation like drag and drop, node editing, node selecting/unSelecting, node expanding/collapsing, node checking/unChecking, adding and removing node. If you pass the ID of TreeView node as arguments for this method then it will return the updated data source of the corresponding node otherwise it will return the entire updated data source of TreeView. The updated data source also contains custom attributes if you specified in data source.

Declaration

public List<TValue> GetTreeData(string node = null)

Parameters

Type	Name	Description
System.String	node	Specifies ID of TreeView node.

Returns

Type	Description
System.Collections.Generic.List<TValue>	"Return TreeData".

MoveNodes(String[], String, Int32, Nullable<Boolean>)

Replaces the text of the TreeView node with the given text.

Declaration

public Task MoveNodes(string[] sourceNodes, string target, int index, Nullable<bool> preventTargetExpand)

Parameters

Type	Name	Description
System.String[]	sourceNodes	Specifies the array of TreeView nodes ID.
System.String	target	Specifies ID of TreeView node.
System.Int32	index	Specifies the index to place the moved nodes in the target element.
System.Nullable<System.Boolean>	preventTargetExpand	If set to true, the target parent node will be prevented from auto expanding.

Returns

Type	Description
System.Threading.Tasks.Task	"Task".

OnAfterRenderAsync(Boolean)

Method invoked after each time the component has been rendered.

Declaration

protected override Task OnAfterRenderAsync(bool firstRender)

Parameters

Type	Name	Description
System.Boolean	firstRender	"First render parameter".

Returns

Type	Description
System.Threading.Tasks.Task	"Task".

Overrides

Syncfusion.Blazor.SfBaseComponent.OnAfterRenderAsync(System.Boolean)

OnInitializedAsync()

Method invoked when the component is ready to start.

Declaration

protected override Task OnInitializedAsync()

Returns

Type	Description
System.Threading.Tasks.Task	"Task".

Overrides

Syncfusion.Blazor.SfBaseComponent.OnInitializedAsync()

OnParametersSetAsync()

Method invoked when any changes in component state occurs.

Declaration

protected override Task OnParametersSetAsync()

Returns

Type	Description
System.Threading.Tasks.Task	"Task".

Refresh()

Applies all the pending property changes and render the component again.

Declaration

public Task Refresh()

Returns

Type	Description
System.Threading.Tasks.Task	"Task".

RemoveNodes(String[])

Removes the collection of TreeView nodes by passing the array of node details as argument to this method.

Declaration

public void RemoveNodes(string[] nodes)

Parameters

Type	Name	Description
System.String[]	nodes	Specifies the array of TreeView nodes ID.

UpdateAnimationProperties(TreeViewNodeAnimationSettings)

Specifies the Animation properties.

Declaration

public void UpdateAnimationProperties(TreeViewNodeAnimationSettings animationSettings)

Parameters

Type	Name	Description
TreeViewNodeAnimationSettings	animationSettings	"Specifies the animation settings".

UpdateChildProperties(String, Object)

Update child property values to TreeView component instance.

Declaration

public void UpdateChildProperties(string key, object details)

Parameters

Type	Name	Description
System.String	key	"Specifies the key field".
System.Object	details	"Specifies the details field".

UpdateNode(String, String)

Replaces the text of the TreeView node with the given text.

Declaration

public Task UpdateNode(string target, string newText)

Parameters

Type	Name	Description
System.String	target	Specifies ID of TreeView node.
System.String	newText	Specifies the new text of TreeView node.

Returns

Type	Description
System.Threading.Tasks.Task	"Task".