I want to get the SID of the selected SNAME which is displayed in the dropwdownliast.I no throught dropdownlist1.selecteditem.text gives the value of the selected text.According to the selected text in the dropdownlist,i want to store the values of SID into a variable.How do i retrieve the values through dataset.

dim para as string
         Dim strConnection As String = "workstation id=SERVER;packet size=4096;user id=sa;data source=server;persist secu" & _
        "rity info=True;initial catalog=students;password=Admin"
        Dim cn As SqlConnection = New SqlConnection(strConnection)
        cn.Open()

        dim strSelect As String = _
        "SELECT SNAME,SID FROM students"
        Dim da As SqlDataAdapter = New SqlDataAdapter(strSelect, cn)
        Dim autogen As New SqlCommandBuilder(da)
        Dim ds As DataSet = New DataSet
        da.Fill(ds,"students")
        DropDownList1.DataSource = ds
        DropDownList1.DataMember = ds.Tables("students").ToString
        DropDownList1.DataValueField = "SNAME"
        DropDownList1.DataBind()

Hi,

Use this method instead of data set.

Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

   Dim sqlcommand As New SqlCommand("SELECT SID FROM students WHERE SNAME= '" & DropDownList1.Text & "'", dbconnection)
   Dim SName As String = sqlcommand.ExecuteScalar()

   MsgBox(SName)

End Sub



Private Sub Form2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

   Dim sqlcommand As New SqlCommand("SELECT SNAME FROM students", dbconnection)
   Dim myReader As SqlDataReader = sqlcommand.ExecuteReader()

   While myReader.Read()
       ComboBox1.Items.Add(myReader("SNAME"))
   End While

End Sub


Please post if you need more information.
Cheers,
   nalla

You may want to consider using prepared statement instead of the …
Dim sqlcommand As New SqlCommand("SELECT SID FROM students WHERE SNAME= '" & DropDownList1.Text & "'", dbconnection)

It is vulnerable to Sql injection (if this is a web app) and the statement will fail if the DropwonList1.Text contain an apostrophe (‘).

May not be a big issue in this case but in general you should be careful about stringing together SQL statements. Personally I do it from time to time, but then I use a general purpose function that takes care of the single apostrophe issue.



Best Regards
Georg Jansen
http://www.l4ndash.com - Log4net Dashboard and Log Viewer