C# Signature:

[DllImport("oleacc.dll")]
public static extern IntPtr AccessibleObjectFromPoint(POINT pt, [Out, MarshalAs(UnmanagedType.Interface)] out IAccessible accObj, [Out] out object ChildID);

VB Signature:

<DllImport("oleacc.dll")> _
    Shared Function AccessibleObjectFromPoint(ByVal pt As Point, <MarshalAs(UnmanagedType.Interface)> ByRef accObj As IAccessible, ByRef ChildID As Object) As IntPtr
    End Function

User-Defined Types:

None.

Alternative Managed API:

The ManagedWindowsApi project (http://mwinapi.sourceforge.net) provides a SystemAccessibleObject class to access accessible objects, that can be instantiated from a point.

Notes:

This function retrieves the lowest-level accessible object in the object hierarchy at a given point in screen coordinates where (0, 0) is the upper left corner. If the element at the point is not an accessible object (that is, does not support IAccessible), then the function retrieves the IAccessible interface of the parent object. The parent object must provide information about the child element through the IAccessible interface.

Tips & Tricks:

Please add some!

Sample Code:

public static IAccessible GetAccessibleObject(POINT pt, out int ChildID)
{
     object varChildID;
     IAccessible accObj;

     IntPtr success = AccessibleObjectFromPoint(pt, out accObj, out varChildID);
     ChildID = (int)varChildID;
     return accObj;
}