If your using RDC for generating Crystal report in your VB appication then use below code
You can put code like this in the General Declarations section.
Dim CRXReport As New CrystalReport1
Dim CRXDatabaseField As CRAXDRT.DatabaseFieldDefinition
Private Sub Form_Load()
Currently there is no sort in this Report. To add the sort field Customer Name, the application must first get the {Customer.Customer Name} field from the Customer Table. This code accesses the first table to get the 2nd field.
Set CRXDatabaseField = CRXReport.Database.Tables.Item(1).Fields.Item(2)
Now add the field to the SortFields Collection and set the Sort Order to ascending.
CRXReport.RecordSortFields.Add CRXDatabaseField, crAscendingOrder