在Discuz中，消息可以分為公用消息(管理后臺 --> 其他 -->公共消息管理)如下：

另外還有批量短消息發送(用戶管理)：

復制代碼 代碼如下:

pmid:自遞增的id
msgfrom:發送者的用戶名，若為系統消息則為“系統”。
msgfromid:發送者的id
msgto:接收者的用戶名
msgtoid:接收者的id
folder: 0、收件箱,1、發件箱,2、草稿箱
new:是否是新消息，未讀，1；0已讀
subject:標題
postdatetime:發送時間
message:消息內容

復制代碼 代碼如下:

/// <summary>
/// 得到公共消息數量
/// </summary>
/// <returns>公共消息數量</returns>
public int GetAnnouncePrivateMessageCount()
{
return Utils.StrToInt(DbHelper.ExecuteScalar(CommandType.Text, "SELECT COUNT(pmid) FROM [" + BaseConfigs.GetTablePrefix + "pms] WHERE [msgtoid] = 0").ToString(), 0);
}


/// <summary>
/// 獲得指定用戶的短信息列表
/// </summary>
/// <param>每頁顯示短信息數</param>
/// <param>當前要顯示的頁數</param>
/// <returns>短信息列表</returns>
public IDataReader GetAnnouncePrivateMessageList(int pagesize, int pageindex)
{
string sql = "";
if(pageindex <= 1)
{
sql = string.Format("SELECT TOP {0} * FROM [{1}pms] WHERE [msgtoid] = 0 ORDER BY [pmid] DESC", pagesize, BaseConfigs.GetTablePrefix);
}
else
{
sql = string.Format("SELECT TOP {0} * FROM [{1}pms] WHERE [msgtoid] = 0 AND [pmid] < (SELECT MIN([pmid]) FROM (SELECT TOP " + (pageindex - 1) * pagesize + " [pmid] FROM [{1}pms] WHERE [msgtoid] = 0 ORDER BY [pmid] DESC) AS tblTmp) ORDER BY [pmid] DESC", pagesize, BaseConfigs.GetTablePrefix);
}

IDataReader reader = DbHelper.ExecuteReader(CommandType.Text, sql);
return reader;
}

復制代碼 代碼如下:

PrivateMessageInfo privatemessageinfo = new PrivateMessageInfo();

string curdatetime = Utils.GetDateTime();
// 收件箱
privatemessageinfo.Message = config.Welcomemsgtxt;
privatemessageinfo.Subject = "歡迎您的加入! (請勿回復本信息)";
privatemessageinfo.Msgto = userinfo.Username;
privatemessageinfo.Msgtoid = uid;
privatemessageinfo.Msgfrom = PrivateMessages.SystemUserName;
privatemessageinfo.Msgfromid = 0;
privatemessageinfo.New = 1;
privatemessageinfo.Postdatetime = curdatetime;
privatemessageinfo.Folder = 0;
PrivateMessages.CreatePrivateMessage(privatemessageinfo, 0);

       執行方法也是讓我感到奇怪，居然是：比如我選擇了乞丐，而乞丐這個等級有10萬用戶，則取得這10W用戶的數據，一條條執行插入。暴汗……這樣算法以及實現確實簡單了很多，但會員一多，要經常清理這些數據。這也是為什么我們看到discuz的論壇經常一段時間需要清理短消息的原因。建議批量發送只對等級較高，數量較少的用戶使用。同時在使用過程中，不明白為什么在“批量短消息發送”中的“文件箱”有“收件箱”、“發件箱”、“草稿箱”3種，這里應該只有“收件箱”比較合適，或者這里根本就不該出現這個“文件箱”。

批量發送的代碼如下：

復制代碼 代碼如下:

private void BatchSendSM_Click(object sender, EventArgs e)
{
#region 批量短消息發送

if (this.CheckCookie())
{
string groupidlist = Usergroups.GetSelectString(",");

if (groupidlist == "")
{
base.RegisterStartupScript( "", "<script>alert('請您先選取相關的用戶組,再點擊提交按鈕');</script>");
return;
}

int percount = 10; //每多少記錄為一次等待
int count = 0; //當前記錄數
// GetUserNameListByGroupid為取得選中的用戶組的所有用戶的id和用戶名
foreach (DataRow dr in DatabaseProvider.GetInstance().GetUserNameListByGroupid(groupidlist).Rows)
{
DatabaseProvider.GetInstance().SendPMToUser(username.Replace("'", "''"), userid, dr["username"].ToString().Replace("'", "''"), Convert.ToInt32(dr["uid"].ToString()), int.Parse(folder.SelectedValue), subject.Text, Convert.ToDateTime(postdatetime.Text), message.Text);
if (count >= percount)
{
Thread.Sleep(3500);
count = 0;
}
count++;
}
base.RegisterStartupScript( "PAGE", "window.location.href='global_sendSMtogroup.aspx';");
}

#endregion
}

//SendPMToUser函數如下：
public void SendPMToUser(string msgfrom, int msgfromid, string msgto, int msgtoid, int folder, string subject, DateTime postdatetime, string message)
{
DbParameter[] parms =
{
DbHelper.MakeInParam("@msgfrom", (DbType)SqlDbType.NVarChar,50, msgfrom),
DbHelper.MakeInParam("@msgfromid", (DbType)SqlDbType.Int, 4, msgfromid),
DbHelper.MakeInParam("@msgto", (DbType)SqlDbType.NVarChar,50, msgto),
DbHelper.MakeInParam("@msgtoid", (DbType)SqlDbType.Int, 4, msgtoid),
DbHelper.MakeInParam("@folder", (DbType)SqlDbType.SmallInt, 2, folder),
DbHelper.MakeInParam("@subject", (DbType)SqlDbType.NVarChar,60, subject),
DbHelper.MakeInParam("@postdatetime", (DbType)SqlDbType.DateTime,8, postdatetime),
DbHelper.MakeInParam("@message",(DbType)SqlDbType.NText, 0,message)
};
string sql = "INSERT INTO [" + BaseConfigs.GetTablePrefix + "pms] (msgfrom,msgfromid,msgto,msgtoid,folder,new,subject,postdatetime,message) " +
"VALUES (@msgfrom,@msgfromid,@msgto,@msgtoid,@folder,1,@subject,@postdatetime,@message)";
DbHelper.ExecuteNonQuery(CommandType.Text, sql, parms);
sql = "UPDATE [" + BaseConfigs.GetTablePrefix + "users] SET [newpmcount]=[newpmcount]+1 WHERE [uid] =@msgtoid";
DbHelper.ExecuteNonQuery(CommandType.Text, sql, parms);
}