Populating a Combobox (with values)

Populating a Combobox (with values)

• Craig Lichtenstein - MSFT

  Thanks alot for the reply (and great advice)...
  But for a simple guy like me who's new to the whole .net thing, I wouldn't how to do any of what you've mentioned (I am pretty new to this whole concept of classes, and OOP so I really don't know how I would go around most of what you've said.)

  I have come this far:
  Public Sub FillMenu()
  Dim conn = DBConn() 'a function the opens a connection to my database
  Dim sqlstr As String = "select * from Form_Table"
  Dim rs = DBrs(conn, sqlstr) 'a function that runs the query and defines RS
  Do While rs.read
  ComboBox1.Items.Add(rs("form_name"))
  Loop
  conn.close()
  End Sub

  All I need to do is add values along with the items. The above code works as it fills the combobox and I can display the selected items with the following code:
  Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBox1.SelectedIndexChanged
  TextBox2.Text = ComboBox1.SelectedItem
  End Sub
  When a user selects an item from the combobox, I'm trying to get the value displayed in another label or a textbox. But since I can't even get the values in the combobox, I'm completely lost... and helpless...
  
  

  
  

• MagicCity33

  OK, you didn't mention that this data was coming from a database. That makes it easier. Just use a DataAdapter to fill a DataTable and then assign the DataTable to the DataSource property of the ComboBox. You then assign the name of the column that you want to display to the DisplayMember property and the name of the code column to the ValueMember property. Then when the user selects an item from the ComboBox the code you want can be retrieved from the SelectedValue property. This is not the most efficient way to do this in terms of performance, but the difference will not be noticeable and it is definitely the easiest way.
  

• Matthew Devine

  hi,

  i thought as well to use hashtable but it didn't work and give me exception when i tried the next code

  Dim hshTbl As New Hashtable

  hshTbl.Add("A", "Egypt First")

  hshTbl.Add("u", "canada")

  hshTbl.Add("E", "france")

  Me.ComboBox1.DataSource = hshTbl

  'Me.ComboBox1.ValueMember = hshTbl.Keys 'or"key" as aspx

  'Me.ComboBox1.DisplayMember = hshTbl.Values ' or"value" as aspx

  but this code worked for me

  Public Class Form1 'this form contain just one combobox Dim table As New DataTable Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load table.Columns.Add("key", GetType(String)) table.Columns.Add("value", GetType(String)) addrow("A", "Egypt") addrow("U", "Canada") addrow("E", "France") ComboBox1.DataSource = table ComboBox1.DisplayMember = "value" ComboBox1.ValueMember = "key" End Sub Private Sub addrow(ByVal key As String, ByVal value As String) Dim row As DataRow = table.NewRow row("key") = key row("value") = value table.Rows.Add(row) End Sub End Class

  hope this helps

  
  
  

• Macca

  you are welcome
  
  

• IJay

  okaban wrote:

  Do While rs.read ComboBox1.Items.Add(rs("form_name")) Loop conn.close() End Sub

  when you add item you just add the display member the best thing is to creat a table and to add records to it while the rs read like for example to replace the previous part of code

  addrow("A", "Egypt")

  whiththis part

  While rs.Read()

  addrow(rs("keycolumnName"), rs("valueColumnName"))

  End While

  
  
  

• Gregfig

  Thank you everyone for your help...
  shakalama - your code worked, and saved me from hours of frustration.

  jmcilhinney - thanks again for the dataadapter advice that also worked.

  I have solved my problem with both solutions. Thanks to everyone who took time to help.
  
  I have been writing ASP and web code for ages but this .net thing is totally different.

  
  

• SonalMS

  You can either create your own type (class or, more likely, structure) that has a property each for the name and the code. You would then create an instance of your type for each item and put them all in an array. You would then assign the array to the DataSource property, the name of the description property to the DisplayMember property and the name of the code property to the ValueMember property. When the user selects a name you can then get the associated code from the SelectedValue property. An alternative would be to use a Hashtable keyed on the names where the values are the codes. You'd then use the selected name in the ComboBox to index the Hashtable to get the corresponding code.
  
• Populating a Combobox (with values)