ITextRangeProvider::MoveEndpointByUnit method (uiautomationcore.h)

Moves one endpoint of the text range the specified number of TextUnit units within the document range.


HRESULT MoveEndpointByUnit(
                TextPatternRangeEndpoint endpoint,
                TextUnit                 unit,
  [in]          int                      count,
  [out, retval] int                      *pRetVal




[in] count

Type: int

The number of units to move. A positive value moves the endpoint forward. A negative value moves backward. A value of 0 has no effect.

[out, retval] pRetVal

Type: int*

Receives the number of units actually moved, which can be less than the number requested if moving the endpoint runs into the beginning or end of the document.

Return value


If this method succeeds, it returns S_OK. Otherwise, it returns an HRESULT error code.


The endpoint is moved forward or backward, as specified, to the next available unit boundary. If the original endpoint was at the boundary of the specified text unit, the endpoint is moved to the next available text unit boundary, as shown in the following illustration.

Illustration showing endpoints of a text range moving If the endpoint being moved crosses the other endpoint of the same text range, the other endpoint is also moved, resulting in a degenerate range and ensuring the correct ordering of the endpoint (that is, that the start is always less than or equal to the end).

ITextRangeProvider::MoveEndpointByUnit deprecates up to the next supported text unit if the given text unit is not supported by the control.

The order, from smallest unit to largest, is listed here.

  • Character
  • Format
  • Word
  • Line
  • Paragraph
  • Page
  • Document

Range behavior when unit is TextUnit::Format

TextUnit::Format as a unit value positions the boundary of a text range to expand or move the range based on shared text attributes (format) of the text within the range. However, using the format text unit should not move or expand a text range across the boundary of an embedded object, such as an image or hyperlink. For more info, see UI Automation Text Units or Text and TextRange Control Patterns.


Minimum supported client Windows XP [desktop apps | UWP apps]
Minimum supported server Windows Server 2003 [desktop apps | UWP apps]
Target Platform Windows
Header uiautomationcore.h (include UIAutomation.h)

See also





Text and TextRange Control Patterns

UI Automation Providers Overview