codice:
Dim custDS As DataSet = New DataSet() 

Dim GustTable As DataTable = custDS.Tables.Add("messaggi") 

Dim pkCol As DataColumn = GustTable.Columns.Add("id", Type.GetType("System.Int32")) 
GustTable.Columns.Add("crono", Type.GetType("System.DateTime")) 
GustTable.Columns.Add("autore", Type.GetType("System.String")) 
GustTable.Columns.Add("email", Type.GetType("System.String")) 
GustTable.Columns.Add("oggetto", Type.GetType("System.String")) 
GustTable.Columns.Add("commento", Type.GetType("System.String")) 
pkCol.AutoIncrement=true 
pkCol.AutoIncrementSeed=1 
pkCol.AutoIncrementStep=1 

GustTable.PrimaryKey = New DataColumn() {pkCol} 

custDS.WriteXml(strPath, XmlWriteMode.WriteSchema)
al posto di strPath devo mettere "file.xml" e x memorizzare qui
("crono", Type.GetType("System.DateTime")) il contenuto di un textbox, come faccio??

grazie
ciao!!