TextSelection Class

Definition

Namespace:Avalonia.Controls

Assembly:Avalonia.Controls.Documents

Package:Avalonia.Controls.Documents

Represents a text selection within a document. Manages selection state with anchor and moving positions for intuitive selection extension.

public class TextSelection

Inheritance: object -> TextRange -> TextSelection

Remarks

Inherits from Avalonia.Controls.Documents.TextModel.TextRange to share formatting and content operations.

Constructors

Name	Description
TextSelection	Initializes a new instance of the Avalonia.Controls.TextSelection class.

TextSelection Constructor

Initializes a new instance of the Avalonia.Controls.TextSelection class.

public TextSelection(Avalonia.Controls.Documents.TextModel.TextDocument document)

Parameters

document Avalonia.Controls.Documents.TextModel.TextDocument

The text document containing the selection.

Methods

Name	Description
ApplyPropertyValue	No summary available.
ClearAllProperties	Clears all inline formatting properties from the range. Content is preserved; only formatting is removed. Produces a single Avalonia.Controls.Documents.Undo.BlockSnapshotUndoUnit for atomic undo/redo. Inherited from TextRange.
ClearPropertyValue	Inherited from TextRange.
ClearSelection	Clears the selection, placing the caret at the current caret position.
ClearSpringloadProperties	Clears all springloaded properties.
ClearSpringloadProperty	Clears a springloaded property.
Contains (2 overloads)	Checks if the range contains the specified pointer. Inherited from TextRange.
CreateSnapshot	Creates an immutable, thread-safe snapshot of this range's document structure. The caller chooses a serializer to convert the snapshot to a specific format. Inherited from TextRange.
Delete	Deletes the selected content, then collapses the selection to the deletion point and resets direction.
DeleteCurrentBlock (2 overloads)	Deletes the block this range starts in, and collapses the range onto the deletion point. Inherited from TextRange.
DeleteText	Deletes the content of this range. Removes whatever the range covers — characters, inline runs, paragraphs, list items, tables, sections — depending on which nodes the range fully encloses. When the deletion crosses block boundaries and both surviving boundary blocks are paragraphs, mergeBlocks controls whether the surviving fragments fuse into one paragraph. Manages transaction automatically. Inherited from TextRange.
DeleteTextAt	Deletes text at the specified range relative to this range. Manages transaction automatically. Inherited from TextRange.
ExtendTo	Extends the selection to a new position while keeping the anchor fixed.
GetContainingBlock	No summary available.
GetPropertyValue	Inherited from TextRange.
GetSpringloadProperties	Gets all springloaded properties.
GetText	Returns the text content covered by this range. Inherited from TextRange.
InsertFootnote	Replaces the range content with a footnote: the anchor (its number as ordinary text) lands at the range position, splitting a run when it sits mid-run, and the note body is created in the document's trailing footnote container with a fresh id - selection delete, anchor, body, and the anchor renumbering are one undo unit. Manages transaction automatically. Inherited from TextRange.
InsertImage	Inherited from TextRange.
InsertPageNumberField	Replaces the range content with a page-number field of kind: the field lands at the range position, splitting a run when it sits mid-run, and shows its cached result until a page layout resolves it (a band on a sheet renders the sheet's number) - selection delete and insertion are one undo unit. Manages transaction automatically. Inherited from TextRange.
InsertSnapshot	Inserts a document snapshot over the selection, then collapses the selection to the end of the inserted content and resets direction.
InsertTextAt	Inserts text at the specified offset relative to the range start. Manages transaction automatically. Inherited from TextRange.
Load	Replaces this range with the content of a stream. Inherited from TextRange.
MoveTo	Moves the caret to the specified position.
Overlaps	Checks if this range overlaps with another range. Inherited from TextRange.
ReplaceText (2 overloads)	Inherited from TextRange.
ReplaceTextAt	Replaces text at the specified range relative to this range. Manages transaction automatically. Inherited from TextRange.
Save	Writes this range to a stream. Inherited from TextRange.
Select	Selects a range of text between two positions.
SelectAll	Selects all content in the document, from Avalonia.Controls.Documents.TextModel.TextDocument.ContentStart to Avalonia.Controls.Documents.TextModel.TextDocument.ContentEnd. ContentEnd anchors to the document's final block, so a trailing empty paragraph is part of the selection (and survives copy).
SetImageAltText	Sets the alternative text of an existing Avalonia.Controls.Documents.RichImage in a single undoable change. Inherited from TextRange.
SetImageSize	Sets the display size of an existing Avalonia.Controls.Documents.RichImage in a single undoable change. Pass double.NaN for a dimension to use the image's intrinsic pixel size. Inherited from TextRange.
SetSpringloadProperty	No summary available.
TogglePropertyValue	No summary available.
ToString	Inherited from TextRange.
TryGetPropertyValue	Inherited from TextRange.
TryGetSpringloadProperty	No summary available.

ApplyPropertyValue Method

public void ApplyPropertyValue<T>(Avalonia.StyledProperty<T> property, T value)

Parameters

property Avalonia.StyledProperty<T>

value T

Type Parameters

T

ClearSelection Method

Clears the selection, placing the caret at the current caret position.

public void ClearSelection()

ClearSpringloadProperties Method

Clears all springloaded properties.

public void ClearSpringloadProperties()

ClearSpringloadProperty Method

Clears a springloaded property.

public void ClearSpringloadProperty(Avalonia.AvaloniaProperty property)

Parameters

property Avalonia.AvaloniaProperty

The property to clear.

Delete Method

Deletes the selected content, then collapses the selection to the deletion point and resets direction.

public Avalonia.Controls.Documents.TextModel.TextPointer Delete()

Returns

Avalonia.Controls.Documents.TextModel.TextPointer

The deletion-point pointer returned by the base operation.

Remarks

The base Avalonia.Controls.Documents.TextModel.TextRange.Delete returns the deletion point but does not reset _isForwardSelection or re-anchor the selection, so cut used to resolve the caret to the wrong endpoint. Re-selecting the returned pointer fixes every delete/cut entry point.

ExtendTo Method

Extends the selection to a new position while keeping the anchor fixed.

public void ExtendTo(Avalonia.Controls.Documents.TextModel.TextPointer position)

Parameters

position Avalonia.Controls.Documents.TextModel.TextPointer

The new moving position.

GetContainingBlock Method

public Avalonia.Controls.Documents.Block GetContainingBlock()

Returns

Avalonia.Controls.Documents.Block

GetSpringloadProperties Method

Gets all springloaded properties.

public System.Collections.Generic.IReadOnlyDictionary<Avalonia.AvaloniaProperty, object> GetSpringloadProperties()

Returns

System.Collections.Generic.IReadOnlyDictionary<Avalonia.AvaloniaProperty, object>

A read-only view of springloaded properties.

InsertSnapshot Method

Inserts a document snapshot over the selection, then collapses the selection to the end of the inserted content and resets direction.

public void InsertSnapshot(Avalonia.Controls.Documents.Serialization.Snapshot.DocumentSnapshot snapshot)

Parameters

snapshot Avalonia.Controls.Documents.Serialization.Snapshot.DocumentSnapshot

The snapshot whose tree is grafted into the selection.

Remarks

The base Avalonia.Controls.Documents.TextModel.TextRange.InsertSnapshot(Avalonia.Controls.Documents.Serialization.Snapshot.DocumentSnapshot) leaves the range spanning the grafted content and never touches selection direction, so paste used to leave a non-collapsed selection whose caret sat one line past the content. Collapsing here re-anchors the caret the same way keyboard edits do via Avalonia.Controls.TextSelection.MoveTo(Avalonia.Controls.Documents.TextModel.TextPointer,bool), fixing every paste entry point (toolbar actions and keyboard).

MoveTo Method

Moves the caret to the specified position.

public void MoveTo(Avalonia.Controls.Documents.TextModel.TextPointer position, bool extendSelection)

Parameters

position Avalonia.Controls.Documents.TextModel.TextPointer

The new caret position.

extendSelection bool

If true, extends selection from anchor to the new position. If false, clears selection and moves both anchor and caret.

Select Method

Selects a range of text between two positions.

public void Select(Avalonia.Controls.Documents.TextModel.TextPointer anchor, Avalonia.Controls.Documents.TextModel.TextPointer moving)

Parameters

anchor Avalonia.Controls.Documents.TextModel.TextPointer

The anchor position where the selection starts.

moving Avalonia.Controls.Documents.TextModel.TextPointer

The moving end position that follows user input.

SelectAll Method

Selects all content in the document, from Avalonia.Controls.Documents.TextModel.TextDocument.ContentStart to Avalonia.Controls.Documents.TextModel.TextDocument.ContentEnd. ContentEnd anchors to the document's final block, so a trailing empty paragraph is part of the selection (and survives copy).

public void SelectAll()

SetSpringloadProperty Method

public void SetSpringloadProperty<T>(Avalonia.StyledProperty<T> property, T value)

Parameters

property Avalonia.StyledProperty<T>

value T

Type Parameters

T

TogglePropertyValue Method

public void TogglePropertyValue<T>(Avalonia.StyledProperty<T> property, T onValue, T offValue)

Parameters

property Avalonia.StyledProperty<T>

onValue T

offValue T

Type Parameters

T

TryGetSpringloadProperty Method

public bool TryGetSpringloadProperty<T>(Avalonia.StyledProperty<T> property, T& value)

Parameters

property Avalonia.StyledProperty<T>

value T&

Type Parameters

T

Returns

bool

Properties

Name	Description
AnchorPosition	Gets the anchor position where the selection started.
CaretPosition	Gets the caret position (the moving end that follows user input during selection).
End	Gets the end position of the range. Inherited from TextRange.
IsEmpty	Gets a value indicating whether the range is empty. A range is empty only when Avalonia.Controls.Documents.TextModel.TextRange.Start and Avalonia.Controls.Documents.TextModel.TextRange.End refer to the exact same document position (node-aware). Two distinct positions that happen to share the same integer offset — for example pointers into consecutive empty paragraphs — are not considered empty. Inherited from TextRange.
Length	Gets the length of the range in characters. Inherited from TextRange.
Start	Gets the start position of the range. Inherited from TextRange.
TextDocument	Gets the document containing this range. Inherited from TextRange.

AnchorPosition Property

Gets the anchor position where the selection started.

public Avalonia.Controls.Documents.TextModel.TextPointer AnchorPosition { get; set; }

CaretPosition Property

Gets the caret position (the moving end that follows user input during selection).

public Avalonia.Controls.Documents.TextModel.TextPointer CaretPosition { get; set; }

Events

Name	Description
Changed	Occurs when the range changes. Inherited from TextRange.