Converting Combobox Value.Member from Sttring to Integer? - vb.net

Question

I have 2 comboboxes which contain ID columns (SID & CID) as the valuemember and the displayMember is text.
I want to use the valueMembers to INSERT into an SQL database.
However the ValueMember property is a String and the column in the database is an Integer.
How can I get these 2 valueMembers converted into Integers.
The code for the complete form is shown below.
Imports System.Data.SqlClient
Imports My_Greeting.Add_VersesDataSetTableAdapters
Public Class frmAddRecord
Private MyDatAdp As New SqlDataAdapter
Private MyDataTbl As New DataTable
Private sql As String = Nothing
Private ds As New DataSet()
Private stepinfo As String = String.Empty
Dim E1 As String
Dim E2 As String
Dim Verse As String
Private connectionString As String = "Data Source=DESKTOP-S7FRNAL\SQLEXPRESS;Initial Catalog=Verses_Find;Integrated Security=True"
Private Sub frmAddRecord_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Me.TopMost = True
Me.WindowState = FormWindowState.Normal
Me.Sub_EventTableAdapter1.Fill(Me.EventSubDataSet1.Sub_Event)
Me.Event_TypeTableAdapter1.Fill(Me.PrimEventDataSet1.Event_Type)
Dim evt As String
Dim SEvt As String
Dim Verse As String
Dim sql As String = Nothing
Dim ds As New DataSet()
Dim stepinfo As String = String.Empty
Try
stepinfo = "Step: instatiate connection"
Using connection As New SqlConnection(connectionString)
stepinfo = "step: test open connection"
connection.Open()
sql = "Select SID, EVENT from Event_Type"
Using adaptor As New SqlDataAdapter(sql, connection)
adaptor.Fill(ds, "Tab_Event_Type")
End Using
stepinfo = "Load second data"
sql = "Select BID,SUBEVENT from Sub_Event"
Using adaptor As New SqlDataAdapter(sql, connection)
adaptor.Fill(ds, "Tab_Sub_Event")
End Using
End Using
stepinfo = "Step: Bind Event combobox"
cboEvent.DataSource = ds.Tables("Tab_Event_Type")
cboEvent.ValueMember = "SID"
cboEvent.DisplayMember = "Event"
stepinfo = "Bind Sub_Event combobox"
cboSEvent.DataSource = ds.Tables("Tab_Sub_Event")
cboSEvent.ValueMember = "BID"
cboSEvent.DisplayMember = "SubEvent"
Catch ex As Exception
MessageBox.Show($"Error:{stepinfo}{vbNewLine}{ex.ToString}")
End Try
evt = cboEvent.ValueMember
SEvt = cboSEvent.ValueMember
Verse = txtNewVerse.Text
E1 = CType(evt, Integer)
E2 = CType(SEvt, Integer)
End Sub
Private Sub btnSave_Click(sender As Object, e As EventArgs) Handles btnSave.Click
Dim query As String = String.Empty
query &= "INSERT INTO Verse (Event, Event_Sub, Verse)"
query &= "VALUES (#Event, #Event_Sub, #Verse)"
Using conn As New SqlConnection("Data Source=DESKTOP-S7FRNAL\SQLEXPRESS;Initial Catalog=Verses_Find;Integrated Security=True")
Using Comm As New SqlCommand()
With Comm
.Connection = conn
.CommandType = CommandType.Text
.CommandText = query
.Parameters.AddWithValue("#Event", E1)
.Parameters.AddWithValue("#Event_Sub", E2)
.Parameters.AddWithValue("#Verse", Verse)
End With
Try
conn.Open()
Comm.ExecuteNonQuery()
Catch ex As Exception
MessageBox.Show(ex.Message.ToString(), "Error Message")
End Try
End Using
End Using
End Sub
End Class
I have tried CInt and CType, but they dont work.
Conversion from string "SID" to type 'Integer' is not valid.

Answer 1

The issue lies in these lines of code:
cboEvent.ValueMember = "SID"
...
Dim evt As String
...
evt = cboEvent.ValueMember
...
Dim E1 As String
...
E1 = CType(evt, Integer)
You can simplify it into
Dim E1 As String = CType("SID", Integer)
Which is obviously not going to work. I'm not sure of your intent, but this is surely your issue.
Edit to address your comments
Here is the title of your question Converting Combobox Value.Member from Sttring [sic] to Integer?
Let's try to figure out what you are trying to do. (By the way, it is nice when we don't need to try to figure out a questioner's intent; rather it is apparent. Anyway, let's do that now)
Regarding this nugget: Combobox Value.Member, it's unclear whether you actually want the ValueMember, SelectedValue, or Text (Text being the closest proxy to Value alone).
The ValueMember tells a control which property to return via SelectedValue when the control is data-bound. For example,
Dim source = (
From i In Enumerable.Range(5, 5)
Select New With {
.Number = i,
.Square = i ^ 2
}).ToList()
ComboBox1.DataSource = source
ComboBox2.DataSource = source
ComboBox2.DisplayMember = "Number"
ComboBox2.ValueMember = "Square"
Let's see what the results of the three properties in question are, for both ComboBoxes
MessageBox.Show($"{ComboBox1.ValueMember}, {ComboBox2.ValueMember}")
, Square
MessageBox.Show($"{ComboBox1.Text}, {ComboBox2.Text}")
{ Number = 5, Square = 25}, 5
MessageBox.Show($"{ComboBox1.SelectedValue}, {ComboBox2.SelectedValue}")
{ Number = 5, Square = 25}, 25
The last one is probably what you want. ComboBox2.ValueMember has been set as the "Square" property of the anonymous type in the LINQ expression.
So in your example, the offending code is in my first code block, and it should be obvious that assigning evt = cboEvent.ValueMember is wrong and that you probably wanted the SelectedValue
evt = cboEvent.SelectedValue
which should have been clear from our comments, and answer. #jmcilhinney's comment specifically
The ValueMember is the name of the member from which the values come. It is NOT the value(s). That's what the SelectedValue property is for. The SelectedValue is where you'll find the value from the specified member of the SelectedItem. – jmcilhinney 16 hours ago
that last part again
16 hours ago
You can lead a horse to water, but you can't make him drink.