在调用“Fill”前，SelectCommand 属性尚未初始化

在调用“Fill”前，SelectCommand 属性尚未初始化

是因为少写了一行代码：

private readonly string strConnection = System.Configuration.ConfigurationManager.AppSettings["ConnStr"].ToString();

private void Form1_Load(object sender, EventArgs e)

        {

            string a = "";

            string sql = " select Date from T_BasicData where userid = '" + a + "'";

            //DataTable DT = Classbase.pubfun.GetSercherGridSource(sql);

            DataTable DT = GetSercherGridSource(sql);

            string b = DT.Rows[][].ToString();

            MessageBox.Show(b);

        }

public  DataTable GetSercherGridSource(string cmdText)

        {

            DataTable DT = null;

            SqlConnection conn = new SqlConnection(strConnection);

            SqlCommand cmd=conn.CreateCommand();

            SqlDataAdapter adp=new SqlDataAdapter();

            adp.SelectCommand = cmd;

            DataSet ds =new DataSet();

            cmd.CommandText=cmdText;

            adp = new SqlDataAdapter();

            try

            {

                conn.Open() ;

                adp.SelectCommand = cmd;//看看有没有这句代码

                adp.Fill(ds)   ;

                if (ds != null)

                {

                    DT = ds.Tables[];

                }

                return DT;

            }

            catch (Exception e)

            {

                //MessageBox.Show("错误");

                //MessageBox.Show(string.Format("异常！以下为数据库提示详细错误信息：{0}{1}", Environment.NewLine, cct.CUR_ERROR), "提示");

                MessageBox.Show(string.Format("异常！以下为数据库提示详细错误信息：{0}{1}", Environment.NewLine, e.Message), "提示");

                //MessageBox.Show(e.Message);

                return DT;

            }

        }