Printing receipt with report viewer problem - vb.net

Question

Im trying to use report viewer to print receipt with pos system but i get always the first order printing details not the current order details
i think the problem with PrintPreview code section where i can put the code exactly
Sub Savepayment()
Try
Dim sdate As String = Now.ToString("yyyy-MM-dd")
Dim stime As String = Now.ToString("hh:mm:ss")
cn.Open()
cm = New SqlCommand("Insert into TblSales(transno,total,sdate,stime,cashier,discount,totalbill) values (#transno,#total,#sdate,#stime,#cashier,#discount,#totalbill) ", cn)
With cm
.Parameters.AddWithValue("#transno", FrmPos.LblTransNo.Text)
.Parameters.AddWithValue("#total", CDbl(TxtBill.Text))
.Parameters.AddWithValue("#sdate", sdate)
.Parameters.AddWithValue("#stime", stime)
.Parameters.AddWithValue("#cashier", str_user)
.Parameters.AddWithValue("#Discount", CDbl(TxtDiscount.Text))
.Parameters.AddWithValue("#totalbill", CDbl(TxtTotal.Text))
'.Parameters.AddWithValue("#Cash", CDbl(TxtCash.Text))
'.Parameters.AddWithValue("#Change", CDbl(TxtChange.Text))
.ExecuteNonQuery()
End With
cn.Close()
cn.Open()
cm = New SqlCommand("Update tblcart set status='Completed' Where transno like '" & FrmPos.LblTransNo.Text & "'", cn)
cm.ExecuteNonQuery()
cn.Close()
MsgBox("Payment successfully Saved!", vbInformation)
With FrmReceipt
.PrintPreview("Select c.id, p.Description, c.price, c.qty, c.total From tblcart as c inner join tblproduct as p on c.pid=p.id where c.status like 'Completed' and TransNo like '" & FrmPos.LblTransNo.Text & "'")
.ShowDialog()
End With
With FrmPos
.LblTransNo.Text = .GetTransNo()
.loadcart()
End With
Me.Dispose()
Catch ex As Exception
cn.Close()
MsgBox(ex.Message, vbCritical)
End Try
End Sub

Answer 1

Your connection should always be declared in the method where is it used with a Using...End Using block. Connection and commands need to be disposed (have their Dispose method called) to release unmanaged resources. Using blocks handle this for us even if there is an error. It also closes the connection.
Don't Open the connection until directly before the Execute... .
Don't use AddWithValue with Sql Server. See http://www.dbdelta.com/addwithvalue-is-evil/
and
https://blogs.msmvps.com/jcoehoorn/blog/2014/05/12/can-we-stop-using-addwithvalue-already/
and another one:
https://dba.stackexchange.com/questions/195937/addwithvalue-performance-and-plan-cache-implications
Here is another
https://andrevdm.blogspot.com/2010/12/parameterised-queriesdont-use.html
You need to disconnect your database code from your user interface code. Show message boxes and interact with controls in the UI code.
I guessed that TransNo is a numeric type, a primary key and a foreign key. If it is an identity field, you should not be sending a value for it. Remove it from the field list, parameter list and the Add method for the Insert command.
Dates should be saved as dates. You will have problems later sorting and searching if they are not dates. I did not change this is the code.
Private cnStr As String = "Your connection String"
Sub Savepayment(TransNo As Integer, TotalBill As Decimal, str_user As String, Discount As Decimal, Total As Decimal)
Dim sdate As String = Now.ToString("yyyy-MM-dd")
Dim stime As String = Now.ToString("hh:mm:ss")
Using cn As New SqlConnection(cnStr)
Using cm As New SqlCommand("Insert into TblSales(transno,total,sdate,stime,cashier,discount,totalbill) values (#transno,#total,#sdate,#stime,#cashier,#discount,#totalbill);", cn)
With cm.Parameters
.Add("#transno", SqlDbType.NVarChar).Value = TransNo
.Add("#total", SqlDbType.Decimal).Value = TotalBill
.Add("#sdate", SqlDbType.NVarChar).Value = sdate
.Add("#stime", SqlDbType.NVarChar).Value = stime
.Add("#cashier", SqlDbType.NVarChar).Value = str_user
.Add("#Discount", SqlDbType.Decimal).Value = Discount
.Add("#totalbill", SqlDbType.Decimal).Value = Total
End With
cn.Open()
cm.ExecuteNonQuery()
End Using
Using cm As New SqlCommand("Update tblcart set status='Completed' Where transno = #TransNo", cn)
cm.Parameters.Add("#TransNo", SqlDbType.Int).Value = TransNo
cm.ExecuteNonQuery()
End Using
End Using
End Sub
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
Dim TransNo = CInt(FrmPos.LblTransNo.Text)
Dim User As String = "I don't know where this comes from"
Dim BillTotal As Decimal
If Not Decimal.TryParse(TxtBill.Text, BillTotal) Then
MessageBox.Show("Please enter a valid number in Total Bill.")
Exit Sub
End If
Dim Discount As Decimal
If Not Decimal.TryParse(TxtDiscount.Text, Discount) Then
MessageBox.Show("Please enter a valid number in Discount")
Exit Sub
End If
Dim TotalAfterDiscount As Decimal
If Not Decimal.TryParse(TxtTotal.Text, TotalAfterDiscount) Then
MessageBox.Show("Please enter a valid number in Total")
Exit Sub
End If
Try
Savepayment(TransNo, BillTotal, User, Discount, TotalAfterDiscount)
MsgBox("Payment successfully Saved!", vbInformation)
Catch ex As Exception
MessageBox.Show(ex.Message)
End Try
'I have no idea what this code is doing.
With FrmReceipt
.PrintPreview("Select c.id, p.Description, c.price, c.qty, c.total From tblcart as c inner join tblproduct as p on c.pid=p.id where c.status like 'Completed' and TransNo like '" & FrmPos.LblTransNo.Text & "'")
.ShowDialog()
End With
With FrmPos
.LblTransNo.Text = .GetTransNo()
.loadcart()
End With
End Sub

Answer 2

I get the solution i add this code of refresh report on the load form event of the report form
ReportViewer1.RefreshReport()