求助高手-这个数据库操作基类的作用

private string InsertEntity(DataRow dsRow, ArrayList aList, string tbName)
        {
            int j = 0;
            string sReturn = "-1";
            string strInsert = "", strValues = "", strField, sValue = "";
            //bool bContinue = true;
            FieldDef Field;
            string strIdentity = "";
            try
            {
                for (j = 0; j < aList.Count; j++)
                {
                    Field = (FieldDef)aList[j];
                    strField = Field.fieldName;
                    if (dsRow.Table.Columns.Contains(strField))
                    {
                        sValue = dsRow[strField].ToString();
                        sValue = sValue.Replace("'", "''");
                        if (Field.bisKey == "1" && Field.sequenceName == "1")
                        {
                            strIdentity = " SELECT @@IDENTITY " + Field.fieldName;
                        }
                        else
                        {
                            if (sValue != "")
                            {
                                if (Field.bisKey == "1")
                                    sReturn = sValue;
                                if (strInsert == "")
                                    strInsert = "insert into " + tbName + "(" + strField;
                                else
                                    strInsert += "," + strField;
                                if (strValues == "")
                                    strValues = "values(";
                                else
                                    strValues += ",";
                                switch (Field.DataType.ToLower())
                                {
                                    case "int":
                                    case "float":
                                        strValues += sValue;
                                        break;
                                    case "date":
                                        strValues += "'" + sValue + "'";
                                        break;
                                    case "varchar":
                                        strValues += "'" + sValue + "'";
                                        break;
                                    case "bit":
                                        if (sValue.ToLower() == "true")
                                            sValue = "1";
                                        else
                                            sValue = "0";
                                        strValues += sValue;
                                        break;
                                    default:
                                        strValues += "'" + sValue + "'";
                                        break;
                                }
                            }
                        }
                    }
                }
                if (strInsert != "")
                {
                    strInsert += ") ";
                    strValues += ")";
                    if (sReturn == "-1")
                        sReturn = "1";
                    if (strIdentity == "")
                    {
                        dbConn.ExecuteSqlWithTrans(strInsert + strValues);
                    }
                    else
                    {
                        sReturn = dbConn.ReturnStringWithTrans(strInsert + strValues + strIdentity);
                    }
                }
            }
            catch (Exception e)
            {
                sReturn = e.ToString();
            }
            return sReturn;        }