GridItemPattern.GridItemPatternInformation.Column Property

 

Gets the ordinal number of the column that contains the cell or item.

Namespace:   System.Windows.Automation
Assembly:  UIAutomationClient (in UIAutomationClient.dll)

public int Column { get; }

Property Value

Type: System.Int32

A zero-based ordinal number that identifies the column containing the cell or item. The default value is 0.

In the following example, an AutomationFocusChangedEvent listener is declared to track the traversal of grid items within a grid container. Item properties are echoed to the console upon each focus-changed event.

///--------------------------------------------------------------------
/// <summary>
/// Obtains a GridItemPattern control pattern from an 
/// automation element.
/// </summary>
/// <param name="targetControl">
/// The automation element of interest.
/// </param>
/// <returns>
/// A GridItemPattern object.
/// </returns>
///--------------------------------------------------------------------
private GridItemPattern GetGridItemPattern(
    AutomationElement targetControl)
{
    GridItemPattern gridItemPattern = null;

    try
    {
        gridItemPattern =
            targetControl.GetCurrentPattern(
            GridItemPattern.Pattern)
            as GridItemPattern;
    }
    // Object doesn't support the 
    // GridPattern control pattern
    catch (InvalidOperationException)
    {
        return null;
    }

    return gridItemPattern;
}
///--------------------------------------------------------------------
/// <summary>
/// Obtains a GridPattern control pattern from an 
/// automation element.
/// </summary>
/// <param name="targetControl">
/// The automation element of interest.
/// </param>
/// <returns>
/// A GridPattern object.
/// </returns>
///--------------------------------------------------------------------
private GridPattern GetGridPattern(
    AutomationElement targetControl)
{
    GridPattern gridPattern = null;

    try
    {
        gridPattern =
            targetControl.GetCurrentPattern(
            GridPattern.Pattern)
            as GridPattern;
    }
    // Object doesn't support the 
    // GridPattern control pattern
    catch (InvalidOperationException)
    {
        return null;
    }

    return gridPattern;
}
///--------------------------------------------------------------------
/// <summary>
/// Set up grid item event listeners.
/// </summary>
/// <param name="targetControl">
/// The grid item container of interest.
/// </param>
///--------------------------------------------------------------------
private void SetGridItemEventListeners(AutomationElement targetControl)
{
    AutomationFocusChangedEventHandler gridItemFocusChangedListener =
        new AutomationFocusChangedEventHandler(OnGridItemFocusChange);
    Automation.AddAutomationFocusChangedEventHandler(
        gridItemFocusChangedListener);
}
///--------------------------------------------------------------------
/// <summary>
/// Event handler for grid item focus change.
/// Can be used to track traversal of individual grid items 
/// within a grid.
/// </summary>
/// <param name="src">Object that raised the event.</param>
/// <param name="e">Event arguments.</param>
///--------------------------------------------------------------------
private void OnGridItemFocusChange(
    object src, AutomationFocusChangedEventArgs e)
{
    // Make sure the element still exists. Elements such as tooltips
    // can disappear before the event is processed.
    AutomationElement sourceElement;
    try
    {
        sourceElement = src as AutomationElement;
    }
    catch (ElementNotAvailableException)
    {
        return;
    }

    // Gets a GridItemPattern from the source of the event.
    GridItemPattern gridItemPattern = 
        GetGridItemPattern(sourceElement);

    if (gridItemPattern == null)
    {
        return;
    }

    // Gets a GridPattern from the grid container.
    GridPattern gridPattern = 
        GetGridPattern(gridItemPattern.Current.ContainingGrid);

    if (gridPattern == null)
    {
        return;
    }

    AutomationElement gridItem = null;
    try
    {
        gridItem = gridPattern.GetItem(
        gridItemPattern.Current.Row, 
        gridItemPattern.Current.Column);
    }
    catch (ArgumentOutOfRangeException)
    {
        // If the requested row coordinate is larger than the RowCount 
        // or the column coordinate is larger than the ColumnCount.
        // -- OR --
        // If either of the requested row or column coordinates 
        // are less than zero.
        // TO DO: error handling.
    }

    // Further event processing can be done at this point.
    // For the purposes of this sample we just report item properties.
    StringBuilder gridItemReport = new StringBuilder();
    gridItemReport.AppendLine(
        gridItemPattern.Current.Row.ToString()).AppendLine(
        gridItemPattern.Current.Column.ToString()).AppendLine(
        gridItemPattern.Current.RowSpan.ToString()).AppendLine(
        gridItemPattern.Current.ColumnSpan.ToString()).AppendLine(
        gridItem.Current.AutomationId.ToString());
    Console.WriteLine(gridItemReport.ToString());
}

///--------------------------------------------------------------------
/// <summary>
/// Handles our application shutdown.
/// </summary>
/// <param name="args">Event arguments.</param>
///--------------------------------------------------------------------
protected override void OnExit(System.Windows.ExitEventArgs args)
{
    Automation.RemoveAllEventHandlers();
    base.OnExit(args);
}

.NET Framework
Available since 3.0
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