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Cursors.SyncRoot Property

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Cursors.SyncRoot Property

Returns an object that can be used to synchronize access to the Cursors collection.

Definition

Visual Basic .NET Public ReadOnly Property SyncRoot As Object
C# public object SyncRoot { get; }
Managed C++ public: __property Object* get_SyncRoot();

Property Value

System.Object. An object that can be used to synchronize access to the Cursors collection.

This property is read-only. This property has no default value.

Remarks

The Cursors collection implements the ICollection Leave Site interface. For more information about the SyncRoot property, see the ICollection.SynchRoot Leave Site property.

Examples

[C#]

This C# example returns a report on the attributes of all the cursors encountered by the InkCollector object passed in as a parameter. It demonstrates using the SyncRoot property of a collection to implement thread-safe iteration.

using Microsoft.Ink;
//. . .
public string CursorReport(InkCollector theInkCollector)
{
    string theReport = "The InkCollector has encountered the following cursors so far:" + Environment.NewLine;
    // Get the Cursors collection from the InkCollector
    Microsoft.Ink.Cursors theCursors = theInkCollector.Cursors;
    // Prevent changes to the collection while we iterate over it.
    lock( theCursors.SyncRoot )
    {
        theReport += "Count of cursors: " + theCursors.Count + Environment.NewLine + Environment.NewLine ;
        foreach (Microsoft.Ink.Cursor cursor in theCursors)
        {
            theReport += "Cursor Name: " + cursor.Name + Environment.NewLine;
            theReport += "Cursor ToString: " + cursor.ToString() + Environment.NewLine;
            theReport += "Tablet Name: " + cursor.Tablet.Name  + Environment.NewLine;
            theReport += "Cursor Id: " + cursor.Id.ToString()  + Environment.NewLine;
            theReport += "Cursor is inverted: " + cursor.Inverted.ToString()  + Environment.NewLine;
            theReport += "Cursor Buttons:" + Environment.NewLine;
            foreach (CursorButton button in cursor.Buttons)
            {
                CursorButtonState theState = button.State;
                theReport += "    Button Name: " + button.Name + Environment.NewLine;
                theReport += "    State: " + button.State.ToString() + Environment.NewLine;
                theReport += "    Id: " + button.Id.ToString()  + Environment.NewLine + Environment.NewLine;
            }
        }
    }
    return theReport;
}

[Visual Basic .NET]

This Microsoft® Visual Basic® .NET example returns a report on the attributes of all the cursors encountered by the InkCollector object passed in as a parameter. It demonstrates using the SyncRoot property of a collection to implement thread-safe iteration.

Imports Microsoft.Ink
'. . .
Public Function CursorReport(ByVal theInkCollector As InkCollector) _
    As String
    Dim theReport As String = "The InkCollector has encountered " & _
        "the following cursors so far:" & vbCrLf
    ' Get the Cursors collection from the InkCollector
    Dim theCursors As Microsoft.Ink.Cursors = theInkCollector.Cursors
    ' Prevent changes to the collection while we iterate over it.
    SyncLock theCursors.SyncRoot
        theReport &= "Count of cursors: " & theCursors.Count & vbCrLf
        Dim theCursor As Microsoft.Ink.Cursor
        For Each theCursor In theCursors
            theReport &= "Cursor Name: " & theCursor.Name & vbCrLf
            theReport &= "Cursor ToString: " & theCursor.ToString() & _
                vbCrLf
            theReport &= "Tablet Name: " & theCursor.Tablet.Name & vbCrLf
            theReport &= "Cursor Id: " & theCursor.Id.ToString() & vbCrLf
            theReport &= "Cursor is inverted: " & _
                theCursor.Inverted.ToString() & vbCrLf
            theReport &= "Cursor Buttons:" & vbCrLf
            Dim theButton As CursorButton
            For Each theButton In theCursor.Buttons
                Dim theState As CursorButtonState = theButton.State
                theReport &= "    Button Name: " & theButton.Name & vbCrLf
                theReport &= "    State: " & _
                    theButton.State.ToString() & vbCrLf
                theReport &= "    Id: " & theButton.Id.ToString() & _
                    vbCrLf & vbCrLf
            Next
        Next
    End SyncLock
    Return theReport
End Function

See Also