see my code

Question

hi 

see my code OF VB.NET, the portion in "IF IsDBNull(table(0)(0) = 0.0) THEN" IS NOT EXECUTED ELSE PORTION EXECUTED, CAN YOU GUIDE ME. DURING

DEBUG TABLE(0)(0) VALUE IS 0D.  BALANCE DATATYPE IS MONEY IN SQL SERVER.

  Using connection As New SqlConnection("Data Source=.\SQLEXPRESS;Initial Catalog=Northwind;Integrated Security=True")
            Dim str1 As String
            str1 = "select top 1 Balance FROM  dbo.PaymentReceived where dbo.PaymentReceived.CustomerName ='" + TextBox2.Text + "' order by ReceivedDate desc"

            Using adapter As New SqlDataAdapter(str1, connection)
                Using table As New DataTable()
                    Try
                        adapter.Fill(table)
                        If IsDBNull(table(0)(0) = 0.0) Then 
                            str1 = "select SUM(receiveable)from PaymentReceived where Balance = 0.0 and dbo.PaymentReceived.CustomerName ='anzar'"
                            Using adapter1 As New SqlDataAdapter(str1, connection)
                                Using table1 As New DataTable()
                                    TextBox5.Text = table1(0)(0)
                                    Label11.Text = table(0)(0)
                                    Label13.Text = Label11.Text
                                End Using
                            End Using

                        Else 'case 2
                            TextBox5.Text = table(0)(0)
                            Label11.Text = table(0)(0)
                            Label13.Text = Label11.Text '- Label12.Text
                            ' TextBox8.Text = Label11.Text - TextBox6.Text

                        End If

                    Catch ex As Exception
                        MsgBox(ex.Message)
                    Finally
                    End Try
                End Using
            End Using
        End Using

THANKS

---

MUHAMMAD ANZAR E-mail : [e-mail] Mobile # :[phone]

Answer 1

In the following line you are comparing table(0)(0) with 0 and it will be true or false depending on the data. 

   If IsDBNull(table(0)(0) = 0.0) Then 

It should be:

If IsDBNull(table(0)(0)) Then 

---

www.cihanyakar.com

Answer 2

HI,

thanks for reply,  see the picture,  in it during debug table(0)(0) value is 0

wait for reply

---

MUHAMMAD ANZAR E-mail : [e-mail] Mobile # :[phone]

Answer 3

But 0 is not DBNull. My guess, you want this:

If IsDBNull(table(0)(0)) OR table(0)(0) = 0  Then 

---

www.cihanyakar.com

Answer 4

Hello,

To avoid ambiguity specify the column name e.g. replace ColumnName below with the column name you are checkinf for a null/nothing value.

Note I did an integer rather than a double, sorry

If table(0)("ColumnName") Is DBNull.Value Then

End If

Mocked example

Dim table As New DataTable
table.Columns.Add(New DataColumn() With {
                     .ColumnName = "ColumnName",
                     .DataType = GetType(Integer)})

table.Rows.Add()

If table(0)("ColumnName") Is DBNull.Value Then
    Console.WriteLine("Null")
Else
    Console.WriteLine("not Null")
End If


table.Rows(0).SetField(Of Integer)("ColumnName", 1)

If table(0)("ColumnName") Is DBNull.Value Then
    Console.WriteLine("Null")
Else
    Console.WriteLine("not Null")
End If

Or tack on value check (and this can be optimized)

Dim table As New DataTable
table.Columns.Add(New DataColumn() With {
             .ColumnName = "ColumnName",
             .DataType = GetType(Integer)})

table.Rows.Add()

If table(0)("ColumnName") Is DBNull.Value Then
    Console.WriteLine("Null")
Else
    Console.WriteLine("not Null")
End If


table.Rows(0).SetField(Of Integer)("ColumnName", 1)

If table(0)("ColumnName") Is DBNull.Value Then
    Console.WriteLine("Null")
Else
    If table(0).Field(Of Integer)("ColumnName") = 1 Then
        Console.WriteLine("Is 1")
    End If
End If

---

Please remember to mark the replies as answers if they help and unmarked them if they provide no help, this will help others who are looking for solutions to the same or similar problem. Contact via my Twitter (Karen Payne) or Facebook (Karen Payne) via my MSDN profile but will not answer coding question on either.

NuGet BaseConnectionLibrary for database connections.

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