首先判断是否存在指定记录，存在则执行更新语句，不存在则执行插入语句。主要用到三个函数：

 public class PubVariant{public static string strUpdateSql = "update CorrespondFields set CadField = @CadField,FieldType = @FieldType,CADTYPE = @CADTYPE"+ " where SdeLayerName = @SdeLayerName and CadLayerName = @CadLayerName and SdeField = @SdeField";public static string strInsertSql = "insert into CorrespondFields values(@SdeLayerName,@CadLayerName,@SdeField,@CadField,@FieldType,@CADTYPE)";}

        /// <summary>/// 判断数据库是否有指定键值的记录/// </summary>/// <param name="str">键值</param>/// <returns>是否存在记录的布尔值</returns>public static bool ExistsRecord(string str){string strSql = "select * from CorrespondFields where SdeField = '" + str + "' and SdeLayerName = '" + PubVariant.sdeLayerName+ "' and CadLayerName = '" + PubVariant.cadLayerName + "'";using (SqlConnection connection = new SqlConnection(PubVariant.ConnectionString)){connection.Open();SqlCommand cmd = new SqlCommand();cmd.Connection = connection;cmd.CommandText = strSql;cmd.CommandType = CommandType.Text;SqlDataReader datareader = cmd.ExecuteReader();return datareader.HasRows;}}/// <summary>/// 执行带参数的Sql语句/// </summary>/// <param name="sqlParas">sql参数数组</param>/// <param name="strSql">要执行的sql语句</param>public static void ExecuteSql(SqlParameter[] sqlParas, string strSql){using (SqlConnection connection = new SqlConnection(PubVariant.ConnectionString)){connection.Open();using (SqlCommand cmd = new SqlCommand(strSql, connection)){foreach (SqlParameter sp in sqlParas){cmd.Parameters.Add(sp);}cmd.ExecuteNonQuery();}}}/// <summary>/// 用datagridview的数据更新数据库/// </summary>/// <param name="dgv">datagridview</param>/// <returns>更新是否成功</returns>public static bool UpdataFromDGVtoDB(DataGridView dgv){try{for (int i = 0; i < dgv.Rows.Count - 1; i++){string strCADTYPE;if (dgv.Rows[i].Cells[1].Value.ToString().StartsWith("[")){strCADTYPE = "1";}else{strCADTYPE = "2";}SqlParameter[] sqlParas = new SqlParameter[]{new SqlParameter("@SdeLayerName", PubVariant.sdeLayerName),new SqlParameter("@CadLayerName", PubVariant.cadLayerName),new SqlParameter("@SdeField", dgv.Rows[i].Cells[0].Value.ToString()),new SqlParameter("@CadField", dgv.Rows[i].Cells[1].Value.ToString()),new SqlParameter("@FieldType", dgv.Rows[i].Cells[2].Value.ToString()),new SqlParameter("@CADTYPE", strCADTYPE)                        };if (ExistsRecord(dgv.Rows[i].Cells[0].Value.ToString())){ExecuteSql(sqlParas, PubVariant.strUpdateSql);}else{ExecuteSql(sqlParas, PubVariant.strInsertSql);}}return true;}catch (Exception ex){MessageBox.Show(ex.Message, "系统提示");return false;}}

转载：http://blog.csdn.net/foreverling/article/details/36390709