Timer control showing -timeout period elapsed error after few minutes

Question

User-1578974752 posted

The Test paper is having Time .My issue is

after 4 to 5 minutes showing error .I have closed all connections using con.close()

still it is coming .The session time in web config I set to 45 minutes as below. The real test will take 45 minutes. How can I solve this . Appreciate the help

<sessionState timeout="45"></sessionState>

</system.web>

Error showing is as below

System.InvalidOperationException: 'Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached.'

Protected Sub tmrMain_Tick(ByVal sender As Object, ByVal e As EventArgs) Handles tmrMain.Tick

Dim timer As UI.Timer = sender

' set current time

Me.txbCurrentTime.Text = DateTime.Now.ToString

' set anchor time by timer control

Me.txbExecutedTime.Text = Me.txbExecutedTime.Text * 1000 - timer.Interval

' show remain executed time

Me.txbExecutedTime.Text = Me.txbExecutedTime.Text / 1000

'If Me.txbExecutedTime.Text = 0 Then

' ' stop timer control

' timer.Enabled = False

' ' Redirecting to anther page

' Response.Redirect("")

'End If

If Me.txbExecutedTime.Text = 600 Then

' stop timer control

' timer.Enabled = False

' Redirecting to anther page

' Response.Write("<script>alert('Only 10 minutes Left')</script>")

MsgBox("Only 10 minutes Left")

End If

If Me.txbExecutedTime.Text = 0 Then

' stop timer control

' timer.Enabled = False

' Redirecting to anther page

Response.Redirect("Result.aspx")

End If

End Sub

<asp:UpdatePanel ID="upMain" runat="server">

<ContentTemplate>

<table>

<tr>

<td class="auto-style149">

<asp:Label ID="Label3" runat="server" Width="140px" Text="Current Time" Visible="False"></asp:Label>

</td>

<td class="auto-style147">

<asp:TextBox ID="txbCurrentTime" runat="server" Width="200px"></asp:TextBox>

</td>

</tr>

<tr>

<td class="auto-style149">Time Left&nbsp; [Sec]</td>

<td class="auto-style147">

<asp:TextBox ID="txbExecutedTime" runat="server" AutoPostBack="True" Width="200px"></asp:TextBox>

</td>

</tr>

</table>

<asp:Timer ID="tmrMain" runat="server" Enabled="False" Interval="1000">

</asp:Timer>

</ContentTemplate>

<Triggers>

<asp:AsyncPostBackTrigger ControlID="tmrMain" EventName="Tick" />

<asp:AsyncPostBackTrigger ControlID="txbExecutedTime" EventName="TextChanged" />

</Triggers>

</asp:UpdatePanel>

Answer 1

User475983607 posted

Error showing is as below

System.InvalidOperationException: 'Timeout expired. The timeout period elapsed prior to obtaining a connection from the pool. This may have occurred because all pooled connections were in use and max pool size was reached.

This error is usually related to not closing DB connections.  Are you making a DB connection in the Page_Load?

The error message always shows the line of code that cause the error in the stack trace... What is that line?

By the way, this code will not work as expected on an actual web server.  It works on your machine because it is both the web server and the client.

MsgBox("Only 10 minutes Left")

Answer 2

User-1578974752 posted

Thanks mgebhard .When I take out the connection string from pagelaod error is gone.

The error showing was in con.Open() and Yes ,it was placed in page load.There are Save,submit and Finish Buttons in the Form.Con.open is placed in the page load hence I don't want to add connection string in the save,submit etc.Timer is also attached in this form.so if I take out connection string from page load I will have to place the connection string in each Buttons repeatedly right? or is there any other way instead of repeatedly placing the connection string

Protected Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click

con = New SqlConnection("Data Source=10.170.10.26;Initial Catalog=Test;Persist Security Info=True;User ID=xxx;Password=xxxx")

con.Open()

Try

cmd = New SqlCommand

cmd.Connection = con

cmd.CommandText = "select * FROM ABMaster where ABMasterID = '" + qusetid.Text + "'"

drd = cmd.ExecuteReader

If drd.HasRows = True Then

drd.Read()

Duration.Text = drd.Item("Duration")

correctansmark.Text = drd.Item("correctanswermark")

End If

Catch ex As Exception

Label2.Text = ex.Message()

Finally

cmd.Dispose()

drd.Close()

con.Close()

End Try

 End Sub

Answer 3

User-893317190 posted

Hi shsu,

If you don't want to declare your connectionstring in every method, you could declare it outside the method so that all methods of  the class could share it.

Also you could read your connectionstring from web.config through the class ConfigurationManager.

Below is my code.

Private Shared connectionString = ConfigurationManager.ConnectionStrings("bjhksjConnectionString").ConnectionString
    Private Shared connectionString2 = "Data Source=.;Initial Catalog=bjhksj;Integrated Security=True"
    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

    End Sub

    Protected Sub Button1_Click(sender As Object, e As EventArgs)
        Using con As SqlConnection = New SqlConnection(connectionString)

            Dim Sql As String = "select * from VBPlan"
            Using com As SqlCommand = New SqlCommand(Sql, con)

                con.Open()
                Using reader As SqlDataReader = com.ExecuteReader()

                    If reader.HasRows Then
                        reader.Read()
                        Label1.Text = reader.Item("id").ToString()
                    End If

                End Using
            End Using
        End Using

    End Sub

And connectionstring in web.config

<configuration>
  <connectionStrings>
    <add name="bjhksjConnectionString" connectionString="Data Source=.;Initial Catalog=bjhksj;Integrated Security=True"
      providerName="System.Data.SqlClient" />
    <add name="EntityExeConnectionString" connectionString="Data Source=.;Initial Catalog=EntityExe;Integrated Security=True"
      providerName="System.Data.SqlClient" />
  </connectionStrings>

For more information about configurationManager, please refer to

https://docs.microsoft.com/en-us/dotnet/framework/data/adonet/connection-strings-and-configuration-files

As you could see, I haven't written  try catch and write using instead. The keyword using could help you release resource and catch exception just as you write try catch and finally.

For more information about using , please refer to  

https://docs.microsoft.com/en-us/dotnet/csharp/language-reference/keywords/using-statement

Best regards,

Ackerly Xu