基于另一个组合框的选择填充组合框

Question

我有两个名为comboBox1和comboBox2的组合框。 cmbbox1中充满了我之前手动添加的项目名称。在选择cmbbox1中的项目后，我想用从数据库中提取的相应供应商填充cmbbox2。某个项目有多个供应商。在这种情况下，我想，以填补组合框2与所有的供应商允许用户选择供应商..

Dim cn As New SqlConnection 
Dim cmd As New SqlCommand 
Dim adapter As New SqlDataAdapter 
Dim dr As SqlDataReader 
Dim dt As New DataTable 

    cn.ConnectionString = ("Data Source=NIMO-HP\SQLEXPRESS;Initial Catalog=FYP_db;Integrated Security=True") 
    cmd.Connection = cn 
    cn.Open() 

    cmd.CommandText = "SELECT comName FROM TblSuppliers WHERE comSitem ='" &  ComboBox1.Text & "'" 
    dr = cmd.ExecuteReader 
    dt.Load(dr) 
    ComboBox2.Text = dt 

Answer 1

尝试这种方式

Dim cn As New SqlConnection 
Dim cmd As New SqlCommand 
Dim adapter As New SqlDataAdapter 
Dim dt As New DataTable 
cn.ConnectionString = ("Data Source=NIMO-HP\SQLEXPRESS;Initial Catalog=FYP_db;Integrated Security=True") 
cn.Open() 
cmd.Connection = cn 
cmd.CommandText = "SELECT comName FROM TblSuppliers WHERE comSitem ='" &  ComboBox1.Text & "'" 
cmd.CommandType = CommandType.Text 
adapter.SelectCommand = cmd 
adapter.Fill(dt) 
ComboBox2.DataSource = dt 
ComboBox2.ValueMember = "comName" 
ComboBox2.DisplayMember = "comName"