new public void Insert(int index, DataSource val) {
val.SetProject(Project);
if ( this.Contains(val) ) {
base.Remove(val);
}
base.Insert(index, val);
}
new public int Add(DataSource val) {
val.SetProject(Project);
if ( !this.Contains(val) ) {
return base.Add(val);
}
return -1;
}