The sqlserver field length is greater than the database table field or the memory table and database table fields do not match the prompt

                DataTable dtCompare = new DataTable();
                dtCompare.Columns.Add("FieldName", typeof(string));
                dtCompare.Columns.Add("FieldType", typeof(string));
                dtCompare.Columns.Add("FieldSize", typeof(int));
                dtCompare.Columns.Add("DbField", typeof(string));
                dtCompare.PrimaryKey = new DataColumn[] { dtCompare.Columns["FieldName"] };

                for (int i = 0; i < DtData.Columns.Count; i++)
                {
                    DataRow dr = dtCompare.NewRow();
                    dr.ItemArray = new object[] {
                        DtData.Columns[i].ColumnName,
                        DtData.Columns[i].DataType.ToString()
                    };
                    dtCompare.Rows.Add(dr);
                }

                DataTable dtDb = con.GetSchema("Columns", new string[] { null, null, this.tableConfig.Table_Struct.TableName });

                List<string> ls = new List<string>();
                for (int i = 0; i < dtCompare.Rows.Count; i++)
                {
                    DataRow dr = dtCompare.Rows[i];
                    string bz = "";
                    string filter = string.Format("COLUMN_NAME='{0}'", dr["FieldName"].ToString());
                    DataRow[] drDbs = dtDb.Select(filter);
                    if (null == drDbs || drDbs.Length == 0)
                        dr["DbField"] = "数据库表无对应字段";
                    if (dr["FieldType"].ToString().Equals("System.String"))
                    {
                        int len = 0;
                        for (int j = 0; j < DtData.Rows.Count; j++)
                        {
                            int len1 = DtData.Rows[j][dr["FieldName"].ToString()].ToString().Length;
                            if (len < len1)
                            {
                                len = len1;
                            }
                        }
                        dr["FieldSize"] = len;
                        if (null != drDbs && drDbs.Length > 0)
                        {
                            dr["DbField"] = "DB:" + drDbs[0]["CHARACTER_MAXIMUM_LENGTH"].ToString();
                        }
                    }

                    ls.Add(string.Format("{0}/{1}/{2}/{3}", dr[0].ToString(), dr[1].ToString(), dr[2].ToString(), dr[3].ToString()));
                }

                string r = string.Join(Environment.NewLine, ls.ToArray());
                throw new Exception(r);