组合框搜索表单加载事件上的第一个索引项。如何停止表单加载事件上的搜索

Question

我在combobox.combobox上根据表单加载事件正确搜索了名称，但它在表单加载事件上选择了第一项，并且还在第一项的基础上进行了搜索。如何在表单加载事件中停止此选择？ ？

我使用combobox1.selectedindex = -1。这不会显示组合框中的任何项目，而是根据组合框中的第一项进行搜索...

   Private Sub Form1_Load(sender As Object, e As EventArgs) Handles 
    MyBase.Load
        Dim con As New SqlConnection
        con.ConnectionString = "data source=abc;initial 
        catalog=LoginDB;integrated security=true"
        cmd.Connection = con
        con.Open()
        cmd.CommandText = "search_data"
        cmd.CommandType = CommandType.StoredProcedure
        Dim dset As New DataSet
        Dim dpt As New SqlDataAdapter
        dpt.SelectCommand = cmd
        dpt.Fill(dset, "tab")
        ComboBox1.DataSource = dset.Tables("tab")
        ComboBox1.DisplayMember = "ID"
        ComboBox1.SelectedIndex = -1
    End Sub

    Private Sub ComboBox1_SelectedIndexChanged(sender As Object, e As 
    EventArgs) Handles ComboBox1.SelectedIndexChanged
        cmd.CommandText = "show_date"
        cmd.CommandType = CommandType.StoredProcedure

        p = New SqlParameter
        p.ParameterName = "@id"
        p.Value = ComboBox1.Text
        cmd.Parameters.Add(p)

        Dim dset As New DataSet
        Dim dpt As New SqlDataAdapter
        dpt.SelectCommand = cmd
        dpt.Fill(dset, "tab")
        If dset.Tables("tab").Rows.Count > 0 Then
        nameTextBox.Text = dset.Tables("tab").Rows(0)("name")
        End If
    End Sub

我希望在加载表单时不进行搜索，而当用户更改项目时在搜索...