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Class TreeViewEvents<TValue> - Blazor API Reference | Syncfusion

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    Class TreeViewEvents<TValue>

    The TreeView allows us to control the component by using events.

    Inheritance
    System.Object
    TreeViewEvents<TValue>
    Namespace: Syncfusion.Blazor.Navigations
    Assembly: Syncfusion.Blazor.dll
    Syntax
    public class TreeViewEvents<TValue> : OwningComponentBase
    Type Parameters
    Name Description
    TValue

    "TValue parameter".

    Constructors

    TreeViewEvents()

    Declaration
    public TreeViewEvents()

    Properties

    Created

    Gets or sets an event callback that is raised when the TreeView component is created successfully.

    Declaration
    public EventCallback<ActionEventArgs> Created { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<ActionEventArgs>

    An event callback function.

    Remarks

    You can perform required actions during this component creation.

    DataBound

    Gets or sets an event callback that is raised when data source is populated in the TreeView.

    Declaration
    public EventCallback<DataBoundEventArgs<TValue>> DataBound { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<DataBoundEventArgs<TValue>>

    An event callback function.

    Remarks

    The data can be modified or updated at this time when the component is updated with data source.

    DataSourceChanged

    Gets or sets an event callback that is raised when data source is changed in the TreeView. The data source will be changed after performing some operation like drag and drop, node editing, adding, and removing node.

    Declaration
    public EventCallback<DataSourceChangedEventArgs<TValue>> DataSourceChanged { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<DataSourceChangedEventArgs<TValue>>

    An event callback function.

    Remarks

    The data source change can be detected and the updated data can be fetched or stored in required cases.

    Destroyed

    Gets or sets an event callback that is raised when the TreeView component is destroyed successfully.

    Declaration
    public EventCallback<ActionEventArgs> Destroyed { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<ActionEventArgs>

    An event callback function.

    Remarks

    Required actions can be performed once the component is destroyed.

    NodeChecked

    Gets or sets an event callback that is raised when the TreeView node is checked/unchecked successfully.

    Declaration
    public EventCallback<NodeCheckEventArgs> NodeChecked { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeCheckEventArgs>

    An event callback function.

    Remarks

    The details of checked/unchecked node can be fetched and required actions can be performed using this event.

    NodeChecking

    Gets or sets an event callback that is raised before the TreeView node is to be checked/unchecked.

    Declaration
    public EventCallback<NodeCheckEventArgs> NodeChecking { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeCheckEventArgs>

    An event callback function.

    Remarks

    Check/uncheck action can be prevented for specific nodes in required cases.

    NodeClicked

    Gets or sets an event callback that is raised when the TreeView node is clicked successfully.

    Declaration
    public EventCallback<NodeClickEventArgs> NodeClicked { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeClickEventArgs>

    An event callback function.

    Remarks

    Required actions can be performed on node click using this event.

    NodeCollapsed

    Gets or sets an event callback that is raised when the TreeView node collapses successfully.

    Declaration
    public EventCallback<NodeExpandEventArgs> NodeCollapsed { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeExpandEventArgs>

    An event callback function.

    Remarks

    Helps to identify that a node is collapsed and the collapsed node details can be fetched in this event.

    NodeCollapsing

    Gets or sets an event callback that is raised before the TreeView node collapses.

    Declaration
    public EventCallback<NodeExpandEventArgs> NodeCollapsing { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeExpandEventArgs>

    An event callback function.

    Remarks

    Collapse action can be prevented for specific nodes in required cases.

    NodeDropped

    Gets or sets an event callback that is raised when the TreeView node is dropped on target element successfully.

    Declaration
    public EventCallback<DragAndDropEventArgs> NodeDropped { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<DragAndDropEventArgs>

    An event callback function.

    Remarks

    Helps to identify the node drop action and the dropped index/target can be fetched to perform required actions.

    NodeEdited

    Gets or sets an event callback that is raised when the TreeView node is renamed successfully.

    Declaration
    public EventCallback<NodeEditEventArgs> NodeEdited { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeEditEventArgs>

    An event callback function.

    Remarks

    Helps to identify that the node is edited successfully and the new edited text can be obtained here.

    NodeEditing

    Gets or sets an event callback that is raised before the TreeView node is renamed.

    Declaration
    public EventCallback<NodeEditEventArgs> NodeEditing { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeEditEventArgs>

    An event callback function.

    Remarks

    Node editing can be prevented for specific nodes using this event.

    NodeExpanded

    Gets or sets an event callback that is raised when the TreeView node expands successfully.

    Declaration
    public EventCallback<NodeExpandEventArgs> NodeExpanded { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeExpandEventArgs>

    An event callback function.

    Remarks

    Helps to identify that a node is expanded and the expanded node details can be fetched using this event.

    NodeExpanding

    Gets or sets an event callback that is raised before the TreeView node is to be expanded.

    Declaration
    public EventCallback<NodeExpandEventArgs> NodeExpanding { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeExpandEventArgs>

    An event callback function.

    Remarks

    Expand action can be prevented for specific nodes in required cases using this event.

    NodeSelected

    Gets or sets an event callback that is raised when the TreeView node is selected/unselected successfully.

    Declaration
    public EventCallback<NodeSelectEventArgs> NodeSelected { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeSelectEventArgs>

    An event callback function.

    Remarks

    Selected node details can be obtained here and updated to required places using this event.

    NodeSelecting

    Gets or sets an event callback that is raised before the TreeView node is selected/unselected.

    Declaration
    public EventCallback<NodeSelectEventArgs> NodeSelecting { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeSelectEventArgs>

    An event callback function.

    Remarks

    A specific node selection can be prevented using this event.

    OnActionFailure

    Gets or sets an event callback that is raised while any TreeView action failed to fetch the desired results.

    Declaration
    public EventCallback<FailureEventArgs> OnActionFailure { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<FailureEventArgs>

    An event callback function.

    Remarks

    You can capture this failure and throw error message for users in required cases.

    OnKeyPress

    Gets or sets an event callback that is raised when key press is successful.

    Declaration
    public EventCallback<NodeKeyPressEventArgs> OnKeyPress { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeKeyPressEventArgs>

    An event callback function.

    Remarks

    Helps to customize the operations at key press.

    OnNodeDragged

    Gets or sets an event callback that is raised when the TreeView node is dragged.

    Declaration
    public EventCallback<DragAndDropEventArgs> OnNodeDragged { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<DragAndDropEventArgs>

    An event callback function.

    Remarks

    Helps to identify the node drag action.

    OnNodeDragStart

    Gets or sets an event callback that is raised when the TreeView node drag (move) starts.

    Declaration
    public EventCallback<DragAndDropEventArgs> OnNodeDragStart { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<DragAndDropEventArgs>

    An event callback function.

    Remarks

    Helps to identify the dragged node details. Dragging can be prevented for specific node in required cases.

    OnNodeDragStop

    Gets or sets an event callback that is raised when the TreeView node dragging (move) stops.

    Declaration
    public EventCallback<DragAndDropEventArgs> OnNodeDragStop { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<DragAndDropEventArgs>

    An event callback function.

    Remarks

    Helps to identify the node drag stop action. Dropped target can be fetched and used to perform required actions.

    OnNodeRender

    Gets or sets an event callback that is raised before the TreeView node is appended to the TreeView element.

    Declaration
    public EventCallback<NodeRenderEventArgs<TValue>> OnNodeRender { get; set; }
    Property Value
    Type Description
    Microsoft.AspNetCore.Components.EventCallback<NodeRenderEventArgs<TValue>>

    An event callback function.

    Remarks

    A specific node can be customized at the time of rendering using this event.

    Methods

    OnInitializedAsync()

    Method invoked when the component is ready to start.

    Declaration
    protected override Task OnInitializedAsync()
    Returns
    Type Description
    System.Threading.Tasks.Task

    A System.Threading.Tasks.Task representing any asynchronous operation.

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