Help In Coding

Help In Coding

• mabster

  It sounds like you're not executing the same query that you gave me as there is a column named LTA, I'm guessing. If you are not using the same query then you will need to provide the query you are using.l You can also try debugging it on your own by using the instrucitons below:
  if you change
  Dim RetVal As Object = objCmd.ExecuteScalar() '
  to
  Dim RetVal As Object' = objCmd.ExecuteScalar() '
  and instead do a
  objCmd.ExecuteNonQuery()
  
  do you still get the same exception
  

• Nicolas Mueggler

  Thanks MarcD! Problem solved thanks to code provided. MVP indeed.
  
  

• abuck

  Maybe i shd show you my Database Table, and data stored (Currrently). The "Dim RetVal As Object = objCmd.ExecuteScalar()" error had been debugged.

  However, another error arise, the "Finally" just before "objconn.close()" had this error, "Conversion failed when converting the nvarchar value 'LTA' to data type int."

  Any idea how to resolve Thks again!

  Event

  EventID                    int  -> Primary Key      3
  EventName             nvarchar(50)                LTA      
  EventTel                  nvarchar(50)                12345678
  EventEmail             nvarchar(50)                LTA@lta.com
  EventStartDate      nvarchar(50)                6/30/2006
  EventEndDate       nvarchar(50)                6/30/2006
  EventStartTime      varchar(10)                 01:00
  EventEndTime       varchar(50)                  02:00
  EventVenue           nvarchar(50)                 LTA
  EventDescription  nvarchar(4000)            LtA Testing

  
  

• Wicket

  Thanks MarcD! I learn something new!

  However, there's an error for in line "Dim RetVal As Object = objCmd.ExecuteScalar() "

  Error Message is as follow "Conversion failed when converting the nvarchar value 'LTA' to data type int."

  It is due to "ExecuteScalar() " can only store int  I just need to display one data, and Value data comes form a combo box "EventCmb", which i wanted to find the selected String, compared to the "Event" database to get the "EventTel" data How do i solved this problem, any advice Thanks!

  
  

• pukla

  Try this code instead. Basically your code was not getting the value into the query. To be secure we used a Named parameter and youwill see where I modified your SQL Query just a bit. The next bit is we ExecuteScalar which returns one value. We check to make sure something was returned and if something was we put it in your label.
  
  
  Dim objConn As New SqlConnection
  Dim objCmd As New SqlCommand
  Dim Value As String = EventCmb.SelectedItem.ToString()
  objConn.ConnectionString = "Data Source=.\SQLEXPRESS;AttachDbFilename='C:\Documents and Settings\HP\My Documents\Visual Studio 2005\WebSites\FYP2\App_Data\Event.mdf';Integrated Security=True;Connect Timeout=30;User Instance=True"
  Try
  objConn.Open()
  objCmd.Connection = objConn
  objCmd.CommandType = CommandType.Text
  objCmd.CommandText = "SELECT EventTel FROM Event WHERE (EventID = @Value)" ' See how i changed Value to @Value. This is called a Named Parameter
  objCmd.Parameters.AddWithValue("@Value", Value) ' Add the @value withthe actual value that should be put. This makes it securer
  Dim RetVal As Object = objCmd.ExecuteScalar() ' This returns the First Column of the first row regardless of how much data is returned.
  If Not ((RetVal Is Nothing) Or (RetVal Is DBNull.Value)) Then
  ContactLbl.Text = RetVal.ToString()
  Else
  ' noting was returned
  End If
  Catch ex As Exception
  Throw ex
  Finally
  objConn.Close()
  End Try
  
  
  
  Hope this helps.
  
  
• Help In Coding