我的應用程序是帶有數據庫的ASP NET MVC 5應用程序。我的數據庫中有一個名爲Logs的表。我希望我的應用程序通知所有客戶端有關該表的新插入,因此我決定使用SignalR + SQLTableDependency。我讀了很多的例子,結合所有的人(但IAM很新的這一切的東西),而這正是我結束了:SignalR SQLTableDependency數據庫更改跟蹤問題
我的日誌實體類:
public class Log
{
public Log(int visitRequestId, string requestNumber)
{
Created = DateTime.Now;
VisitRequestId = visitRequestId;
RequestNumber = requestNumber;
}
public Log()
{
}
[DatabaseGenerated(DatabaseGeneratedOption.Identity), Key]
public int Id { get; set; }
[Required]
public int VisitRequestId { get; set; }
public string RequestNumber { get; set; }
public DateTime Created { get; set; }
public string Message { get; set; }
}
我singletone服務類:
public class JournalMessangesService
{
private static readonly Lazy<JournalMessangesService> _instance = new Lazy<JournalMessangesService>(()=>new JournalMessangesService(GlobalHost.ConnectionManager.GetHubContext<JournalMessageHub>().Clients));
private static SqlTableDependency<Log> _tableDependency;
private IHubConnectionContext<dynamic> Clients { get; }
public static JournalMessangesService Instance => _instance.Value;
private JournalMessangesService(IHubConnectionContext<dynamic> clients)
{
Clients = clients;
_tableDependency = new SqlTableDependency<Log>(
ConfigurationManager.ConnectionStrings["EFDbContext"].ConnectionString,
"Logs"
);
_tableDependency.OnChanged += SqlTableDependency_Changed;
_tableDependency.OnError += SqlTableDependency_OnError;
_tableDependency.Start();
}
private void SqlTableDependency_OnError(object sender, ErrorEventArgs e)
{
throw e.Error;
}
private void SqlTableDependency_Changed(object sender, RecordChangedEventArgs<Log> e)
{
if (e.ChangeType != ChangeType.None)
{
BroadcastJournalMessage(e.Entity);
}
}
private void BroadcastJournalMessage(Log log)
{
Clients.All.updateMessage(log);
}
public IEnumerable<Log> GetAllLogs()
{
var logEntries = new List<Log>();
var connString = ConfigurationManager.ConnectionStrings["EFDbcontext"].ConnectionString;
using (var connection = new SqlConnection(connString))
{
connection.Open();
using (var command = connection.CreateCommand())
{
command.CommandText = "SELECT * FROM [Logs]";
using (var dataReader = command.ExecuteReader())
{
while (dataReader.Read())
{
var id = dataReader.GetInt32(dataReader.GetOrdinal("VisitRequestId"));
var reqNum = dataReader.GetString(dataReader.GetOrdinal("RequestNumber"));
var created = dataReader.GetDateTime(dataReader.GetOrdinal("Created"));
var message = dataReader.GetString(dataReader.GetOrdinal("Message"));
logEntries.Add(new Log(id, reqNum) {Created = created, Message = message});
}
}
}
}
return logEntries;
}
#region IDisposable Support
private bool disposedValue = false; // To detect redundant calls
protected virtual void Dispose(bool disposing)
{
if (!disposedValue)
{
if (disposing)
{
_tableDependency.Stop();
}
disposedValue = true;
}
}
~JournalMessangesService()
{
Dispose(false);
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
#endregion
}
我的HUB類:
[HubName("journalMessageHub")]
public class JournalMessageHub : Hub
{
private readonly JournalMessangesService _journalMessangesService;
public JournalMessageHub() : this(JournalMessangesService.Instance) { }
public JournalMessageHub(JournalMessangesService journalMessangesService)
{
_journalMessangesService = journalMessangesService;
}
public IEnumerable<Log> GetAllLogs()
{
return _journalMessangesService.GetAllLogs();
}
}
我還添加了app.MapSignalR();
我啓動的.cs。
這裏是我的HTML視圖:
<script src="~/Scripts/jquery.signalR-2.2.2.js"></script>
<script src="/signalr/hubs" type="text/javascript"></script>
<script src="~/Scripts/noty.js"></script>
<script type="text/javascript">
$(document).ready(function() {
var journalHub = $.connection.journalMessageHub;
journalHub.client.updateMessage = function(log) {
new Noty({
text: log.Message,
type: 'warning',
theme: 'metroui',
timeout: '2000'
}).show();
};
$.connection.hub.start().done(function() {
journalHub.server.getAllLogs().done(function(data) {
console.log('data length: ' + data.length);
});
journalHub.client.updateMessage();
});
});
我想要的是得到一個通知(通過Noty.js,但它不」物)時,有一個插入INT我的日誌數據庫表。但是用我的代碼我沒有得到那個結果 - 通知被觸發,但是它們不包含任何內部的日誌數據,只有一些'未定義'的東西。
另一個問題是我不想在頁面刷新時觸發通知 - 最初是在數據庫更改時。
我想我對我的代碼的JavaScript部分有一些誤解,但它可以是其他任何東西 - 我完全是所有這些網絡的新東西。
請幫助我,我再也看不到所有這些StockTicker示例,它們不適用於我。
非常感謝您的幫助。