Crystal Reports through Dataset

vconn = New SqlConnection("Data Source=.\SQLEXPRESS;AttachDbFilename=C:\Documents and Settings\GTB\My Documents\Visual Studio 2005\Projects\MyInstitute\Database1.mdf;Integrated Security=True;User Instance=True")
vconn.Open()
vadapter = New SqlDataAdapter("select * from students", vconn)
vdataset = New DataSet
vadapter.Fill(vdataset, "students")
vdatatable = vdataset.Tables("students")
Dim a As New CrystalReport1
a.Database.Tables(0).SetDataSource(vdataset)
CrystalReportViewer1.ReportSource = a