SqlConnection con1 = new SqlConnection("server=.;database=dxdata;uid=sa;pwd=");
            string sql1 = " select 字段1 from 表1 where 受理编号='" + this.textBox1.Text + "'union all select 字段2 from 表2 where 受理编号='" + this.textBox1.Text + "'";
            DataSet ds1 = new DataSet();
            SqlDataAdapter adapter1 = new SqlDataAdapter(sql1, con1);
            try
            {
                adapter1.Fill(ds1, "表1");
                for (int i = 0; i < ds1.Tables[0].Rows.Count; i++)
                {
                    comboBox2.Items.Add(ds1.Tables[0].Rows[i]["字段1"].ToString());
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }            SqlConnection con = new SqlConnection("server=.;database=dxdata;uid=sa;pwd=");
            string sql = "select * from  [dbo].[表1]  where 受理编号 = '" + this.textBox1.Text + "'";
            DataSet ds = new DataSet();
            SqlDataAdapter adapter = new SqlDataAdapter(sql, con);
            try
            {
                adapter.Fill(ds, "表1");
                if (ds.Tables[0].Rows.Count > 0)
                {
                    textBox3.Text = ds.Tables[0].Rows[0]["字段3"].ToString();
                    textBox4.Text = ds.Tables[0].Rows[0]["字段4"].ToString();
                    button3.Enabled = true;
                }
                else
                {
                    MessageBox.Show("受理编号输入有误或该受理号不存在,请核实!", "提示", MessageBoxButtons.OK, MessageBoxIcon.Information);
                    textBox1.Text = null;
                    textBox1.Focus();
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
文字加粗的那段代码好像始终没有执行,请教问题出在哪里