Question

What I want to do here is that for every new item added into the ComboBox, a Label’s text property will display +1 from the previous number.

How do I write it out, assuming I didn’t assign the items a number.

Items              Label
Tom                 1
Jane                2
Mary                3
John                4
etc..               etc..

Edit: My ComboBox is binded to a data source.

Private Sub btnSave_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSave.Click

    Dim studentcheck = StudentTableAdapter.checkstudent(StudentNameTextBox.Text, StudentAddressTextBox.Text)

    If StudentNameTextBox.Text.Length = 0 Then

        MsgBox("Name is Empty")

    ElseIf StudentAddressTextBox.Text.Length = 0 Then

        MsgBox("Address is empty")

    ElseIf studentcheck Is Nothing Then

        Me.Validate()
        Me.StudentBindingSource.EndEdit()
        Me.TableAdapterManager.UpdateAll(Me.LibraryDataSet)
        frmAddLoan.DisplayLoanTableAdapter.Fill(frmAddLoan.LibraryDataSet.DisplayLoan)
        frmAddLoan.ComboBox1.Update()
        MsgBox("Student Info Added")

    Else

        MsgBox("Student Name and Address have been used.")

    End If

End Sub

Answer 1

Try using this code.

Private Sub ComboBox1_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ComboBox1.SelectedIndexChanged

    label1.Text = (ComboBox1.selectedIndex+1).ToString()

End Sub