.net简单的三层实现功能(8)

190         {
191             using (DbConnection connection = GetConnection())
192             {
193                 DbCommand command = GetCommand(cmdText, CommandType.Text, connection);
194                 connection.Open();
195                 object val = command.ExecuteScalar();
196                 command.Parameters.Clear();
197                 return val;
198             }
199         }
200
201         /// <summary>
202         /// 执行有返回值有参数的sql语句
203         /// </summary>
204         /// <param name="cmdText"></param>
205         /// <param name="para"></param>
206         /// <returns></returns>
207         public static object ExecuteScalar(string cmdText, Dictionary<string, object> para)
208         {
209             using (DbConnection connection = GetConnection())
210             {
211                 DbCommand command = GetCommand(cmdText, CommandType.Text, connection);
212                 foreach (KeyValuePair<string, object> p in para)
213                 {
214                     command.Parameters.Add(GetParameter(p.Key, p.Value, command));
215                 }
216                 connection.Open();
217                 object val = command.ExecuteScalar();