I got solution:
con = New SqlConnection(ConfigurationManager.ConnectionStrings("dbcon").ToString())
con.Open()
Dim rptdoc As New ReportDocument
Dim dt As New DataTable
ds = New DataSet
cmd.CommandText = "sp_studentrec"
cmd.CommandType = CommandType.StoredProcedure
cmd.Connection = con
cmd.Parameters.Add("@Sno", SqlDbType.Int).Value = txtsno.Text
da.SelectCommand = cmd
da.Fill(ds)
dt = ds.Tables(0)
rptdoc.Load(Server.MapPath("CryStudentReport.rpt"))
rptdoc.SetDataSource(dt)
CrystalReportViewer1.ReportSource = rptdoc
CrystalReportViewer1.Visible = True
con.Close()