To iterate through the values of combo box control using vb.net

Question

I update my question here .. Am using a combo box with no of phone numbers .I want to get the phone no one by one in a variable. Now am using the below code to get the combobox values. But still now am getting the following error message System.Data.DataRowView. Please help me to fix this error. am new for vb.net.

My partial code is here ..

        For i = 0 To ComboBox1.Items.Count
            Dim s As String

            s = Convert.ToString(ComboBox1.Items(i))
        Next i

Answer 1

you are using an index which is zero based.

change this:

For i = 0 To ComboBox1.Items.Count

to this:

For i = 0 To ComboBox1.Items.Count - 1

Answer 2

Your problem probably happens here:

s = Convert.ToString(ComboBox1.Items(i))

This doesn't return the value. It returns a string representation of the object at the given index, which in your case apparently is of type System.Data.DataRowView.

You would have to cast ComboBox1.Items(i) to the approbriate type and access its Value. Or, since its a DataRowView, you can access the values throgh the appropriate column names:

Dim row = CType(ComboBox1.Items(i), System.Data.DataRowView)
s = row.Item("column_name")

Nevertheless, first of all you should definitely close and dispose the connection, no matter whether the transaction fails or succeeds. This can be done in a finally block (option 1) or with a using statement (option 2).

Option 1

// ...
con1 = New MySqlConnection(str)
con1.Open()
Try
    // ...
Catch ex As Exception
    Lblmsg.Text = " Error in data insertion process....." + ex.Message
Finally
    con1.Close()
    con1.Dispose()
End Try

Option 2

// ...
Using con1 as New MySqlConnection(str)
    con1.Open()
    Try
        // ...
    Catch ex As Exception
        Lblmsg.Text = " Error in data insertion process....." + ex.Message
    Finally
        con1.Close()
    End Try
End using

Answer 3

This also works!

        Dim stgTest = "Some Text"
        Dim blnItemMatched As Boolean = False

        '-- Loop through combobox list to see if the text matches
        Dim i As Integer = 0
        For i = 0 To Me.Items.Count - 1
            If Me.GetItemText(Me.Items(i)) = stgTest Then
                blnItemMatched = True
                Exit For
            End If
        Next i

        If blnItemMatched = False Then

            Dim stgPrompt As String = "You entered  '" & stgTypedValue & "',  which is not in the list."
            MessageBox.Show(stgPrompt, "Incorrect Entry", MessageBoxButtons.OK, MessageBoxIcon.Information)

            Me.Text = ""
            Me.Focus()

        End If

Answer 4

Even after long time back you will achieve this with simply by following

For Each item As Object In combx.Items

    readercollection.Add(item.ToString)

        Next