lwordtask.cs

随便上传一文章 随便上传一文章 随便上传一文章 随便上传一文章

using System;
using System.Collections;
using System.Data;
using System.Data.OleDb;
using System.Web;

using TraceLWord4.Classes;		// 引用实体规范层

namespace TraceLWord4.AccessTask
{
	/// <summary>
	/// LWordTask 留言板任务类
	/// </summary>
	public class LWordTask
	{
		// 数据库连接字符串
		private const string DB_CONN=@"PROVIDER=Microsoft.Jet.OLEDB.4.0; DATA Source=C:\DbFs\TraceLWordDb.mdb";

		/// <summary>
		/// 读取 LWord 数据表，返回留言对象数组
		/// </summary>
		/// <returns></returns>
		public LWord[] ListLWord()
		{
			// 留言对象集合
			ArrayList lwordList=new ArrayList();

			string cmdText="SELECT * FROM [LWord] ORDER BY [LWordID] DESC";

			OleDbConnection dbConn=new OleDbConnection(DB_CONN);
			OleDbCommand dbCmd=new OleDbCommand(cmdText, dbConn);

			try
			{
				dbConn.Open();
				OleDbDataReader dr=dbCmd.ExecuteReader();

				while(dr.Read())
				{
					LWord lword=new LWord();

					// 设置留言编号
					lword.UniqueID=(int)dr["LWordID"];
					// 留言内容
					lword.TextContent=(string)dr["TextContent"];
					// 发送时间
					lword.PostTime=(DateTime)dr["PostTime"];

					// 加入留言对象到集合
					lwordList.Add(lword);
				}
			}
			catch
			{
				throw;
			}
			finally
			{
				dbConn.Close();
			}

			// 将集合转型为数组并返回给调用者
			return (LWord[])lwordList.ToArray(typeof(TraceLWord4.Classes.LWord));
		}

		/// <summary>
		/// 发送留言信息到数据库
		/// </summary>
		/// <param name="newLWord">留言对象</param>
		public void PostLWord(LWord newLWord)
		{
			// 留言内容不能为空
			if(newLWord==null || newLWord.TextContent==null || newLWord.TextContent=="")
				throw new Exception("留言内容为空");

			string cmdText="INSERT INTO [LWord]([TextContent]) VALUES(@TextContent)";

			OleDbConnection dbConn=new OleDbConnection(DB_CONN);
			OleDbCommand dbCmd=new OleDbCommand(cmdText, dbConn);

			// 设置留言内容
			dbCmd.Parameters.Add(new OleDbParameter("@TextContent", OleDbType.LongVarWChar));
			dbCmd.Parameters["@TextContent"].Value=newLWord.TextContent;

			try
			{
				dbConn.Open();
				dbCmd.ExecuteNonQuery();
			}
			catch
			{
				throw;
			}
			finally
			{
				dbConn.Close();
			}
		}
	}
}