gtk-sharp >Gtk# is thread aware, but not thread safe; See the Gtk# Thread Programming for details. System.Attribute System.AttributeUsage(System.AttributeTargets.Property | System.AttributeTargets.Field | System.AttributeTargets.All, AllowMultiple=true) An attribute to identify a property as a tree node column value. This attribute is applied to a property of a tree node class to indicate that the property holds a column value of the node. In the following example, the Frombulator property is tagged as Column 2 of the node which implements it: [TreeNodeValue(Column=2)] public string Frombulator { get { return frombulator; } } Constructor TreeNodeValueAttribute constructor Instantiates a Property System.Int32 Column named value a The column number of the value which is exposed by the property this marks.