[ Version ( since = "0.4.0" ) ]
public string value_string { get; set; }
A simple string value used to name this when.
It allows UIs to display a label such as "Work", "Volunteer", "Professional Society", etc.
For more information, see the <ulink type="http" url="http://code.google.com/apis/gdata/docs/2.0/elements.html#gdWhen">GData specification</ulink>.