private void Form1_Loadobject sender EventArgs e 读取ERP生产部门的值 执行SQL查询语句让cbx_p_cat显示已有的类别 SqlConnection conn = new SqlConnectionerpConnString; connOpen; string query = select depname fr

您可以在加载Form1时，将默认显示值添加到cboDept的数据源中。修改代码如下：

private void Form1_Load(object sender, EventArgs e) { // 读取ERP生产部门的值 // 执行SQL查询语句,让cbx_p_cat显示已有的类别 SqlConnection conn = new SqlConnection(erpConnString); conn.Open(); string query = "select dep,name from dept where make_id in (1,3)"; SqlCommand command = new SqlCommand(query, conn); SqlDataAdapter adapter = new SqlDataAdapter(command); DataTable dataTable = new DataTable(); adapter.Fill(dataTable);

// 添加默认显示值
DataRow defaultRow = dataTable.NewRow();
defaultRow["dep"] = "默认显示值";
defaultRow["name"] = "选生产部门";
dataTable.Rows.InsertAt(defaultRow, 0);

// 设置cboDept的显示值和对应的数据值
cboDept.DisplayMember = "name";
cboDept.ValueMember = "dep";
cboDept.DataSource = dataTable;

// 设置label1显示对应的dep
label1.DataBindings.Add("Text", dataTable, "dep");