combobox绑定dataset，但是点击combobox下拉菜单的时候什么都没有？

C# code

private void comboBox商品品牌_SelectedIndexChanged(object sender, EventArgs e)
        {
            string source = "server=(local)\\ SQLEXPRESS;" + "Integrated Security=True;" + "Database=Goods";
            using (SqlConnection conn = new SqlConnection(source))
            {
                conn.Open();
                string select = "select * from RestGoods";
                SqlDataAdapter da = new SqlDataAdapter(select, conn);
                //SqlCommandBuilder bu = new SqlCommandBuilder(da);
                DataSet ds = new DataSet();
                da.Fill(ds, "RestGoods");
                comboBox商品品牌.DataSource = ds.Tables["RestGoods"];
                comboBox商品品牌.DisplayMember = "商品品牌";
                comboBox商品品牌.ValueMember = "商品品牌";
            }
        }

大虾们帮我看看

------解决方案--------------------
.DataBind()
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comboBox商品品牌.DataBind()
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没绑定撒
------解决方案--------------------
winform的吧
你看看DataSet里面有没有数据
还有“商品品牌”是RestGoods表中的字段么？
------解决方案--------------------
设个断点到这里，或者
private void comboBox商品品牌_SelectedIndexChanged(object sender, EventArgs e)
{
string source = "server=(local)\\ SQLEXPRESS;" + "Integrated Security=True;" + "Database=Goods";
using (SqlConnection conn = new SqlConnection(source))
{
conn.Open();
string select = "select * from RestGoods";
SqlDataAdapter da = new SqlDataAdapter(select, conn);
//SqlCommandBuilder bu = new SqlCommandBuilder(da);
DataSet ds = new DataSet();
da.Fill(ds, "RestGoods");
if(ds!=null&&ds.tables.count>0&&ds.tables[0].rows.count>0)
{
messagebox.show(ds.Tables["RestGoods"].rows.count.tostring());
}
else
{ 
messagebox.show("没有数据");

}
}
}
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一般我会怎么写.
直接查列名效率也高.
还有你这个功能写在SelectedIndexChanged事件第一次肯定不妥.建议写到LOAD事件里.

private void comboBox商品品牌_SelectedIndexChanged(object sender, EventArgs e)
{
string source = "server=(local)\\ SQLEXPRESS;" + "Integrated Security=True;" + "Database=Goods";
using (SqlConnection conn = new SqlConnection(source))
{
conn.Open();
string select = "select 列名 from RestGoods"; //列名为你需要绑定到COMBOBOX的列值.
SqlDataAdapter da = new SqlDataAdapter(select, conn);
//SqlCommandBuilder bu = new SqlCommandBuilder(da);
DataSet ds = new DataSet();
da.Fill(ds, "RestGoods");
comboBox商品品牌.DataSource = ds.Tables["RestGoods"];
comboBox商品品牌.DataBind();
}
}
------解决方案--------------------
这个用控件做比较简单
先用sqlDataAdapter创建SlecetCommand，然后创建DataSet，在ComBox里DataSource里选择DataSet.表名，在DisplayMember选择列名
在Formload里写上sqlDataAdapter.Fill(DataSet)就可以了