在组合框中添加项目

Question

我想添加一个项目到combobox，它已经在一些数据界限。

代码：

Public Sub showSection() 
     sb = New StringBuilder() 
     sb.Remove(0, sb.Length) 
     sb.Append("SELECT DISTINCT Section ") 
     sb.Append(" FROM Employee ") 
     sb.Append(" ORDER BY Section") 
     Dim sqlSection As String = sb.ToString() 

     da = New SqlDataAdapter(sqlSection, Conn) 
     da.Fill(ds, "Section") 

     dt = ds.Tables("Section") 
     bs.DataSource = dt 

     With cbSection 
      .DisplayMember = "Section" 
      .ValueMember = "Section" 
      .DataSource = ds.Tables("Section") 
      .DataBindings.Add("SelectedValue", bs, "Section") 
     End With 
End Sub 

但我想补充的项目，像"---All---"，所以这应该是输出。

---All--- 
HR 
Store 
Packing 
Training 
Qc 
Qa 
Stock 

Answer 1

下面是简单的解决方案

Dim dr As DataRow = dt.NewRow() 
dr("Section") = "---All---" 
dr("SectionId") = 0 
dt.Rows.InsertAt(dr, 0) 

With cbSection 
    .DisplayMember = "Section" 
    .ValueMember = "SectionId" 
    .DataSource = ds.Tables("Section") 
    .DataBindings.Add("SelectedValue", bs, "Section") 
End With 

cbSection.SelectedIndex = 0