DataTable的使用。（将数据列信息赋值给指定的控件）

string str="select * from pe_production where id='"+TextBox23.Text.Trim()+"'";

tb=updata.ExecuteSql4Ds(str).Tables[0];

if(tb.Rows.Count>0)

{

     BindDropDownList1();//从数据库中绑定数据，删除此行，必须手动绑定DropDownList1中信息

     TextBox1.Text=tb.Rows[0][2].ToString().Trim();

     TextBox3.Text=tb.Rows[0][5].ToString().Trim();

     string DropDown1=tb.Rows[0][3].ToString().Trim();

     for (int i=0;i<DropDownList1.Items.Count;i++)

        {

            if (DropDownList1.Items[i].ToString().Trim() == DropDown1)                                     

              {

                  DropDownList1.SelectedIndex = i;

                  BindDropDownList2();

                  BindDropDownList3();

                  break;

              }

        }

}