public virtual void AddChild(IProjectItem child)
{
for (IProjectItem i = this.Parent; i != null; i = i.Parent)
{
if (i == child)
{
return;
}
}
IProjectItem parent = child.Parent;
if (parent != null)
{
parent.RemoveChild(child);
}
this.children.Add(child);
child.Parent = this;
}