Visual Basic

Christian Graus12-Jun-07 16:20

Christian Graus

12-Jun-07 16:20

A web site and a database server are two differnt things, having your site live doesn't mean your database can be connected to, via the web ( thank goodness ). The logical thing to do here is to write a web service, which has methods to access the DB, and one to return a user count, if you want it.

Christian Graus - Microsoft MVP - C++
Metal Musings - Rex and my new metal blog
"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

Socheat.Net12-Jun-07 16:29

Socheat.Net

12-Jun-07 16:29

I don't understand what you mean, can you clearify my question?

Socheat

Christian Graus12-Jun-07 18:44

Christian Graus

12-Jun-07 18:44

I can clarify my answer - having a web site that is live, doesn't in any way expose any database that may be in use on that web site. You need a web service to do that, with methods that call the database.

Help understanding Dim args = New Object() {myObject}

Socheat.Net12-Jun-07 20:44

Socheat.Net

12-Jun-07 20:44

So, can you give me an example?

Socheat

Share Point

alexfromto12-Jun-07 14:05

alexfromto

12-Jun-07 14:05

Hi guys.

My company just bought and installed Share Point. I hope someone has/had experience with Share Point and can point me to the right direction. I just need some guidance for development.

As a .NET developer I need to know how do I create and integrate my applications (we have bunch of them (that I built) which are used by different departments within the company. For example: We will use Share Point as Intranet (calendars, documents, project flows, etc) so how do I create and integrate custom made application into Share Point Intranet? I have never used Share Point but heard some things about it (easy to use, great value, etc.) so please understand my confusion and forgive me if I ask stupid questions?

Any books, links, examples will be greatly appreciated.

Thanks a lot.

twista12-Jun-07 12:15

twista

12-Jun-07 12:15

Hi,

I'm using the invoke method on some reflection, and don't really understand what I'm passing into the function.

My function passes an object reference which needs to be passed down into the reflected assembly.
The assembly then creates an object and then passes a reference back to this newly created object through the passed in object "ConfigObj"

<br />
  Public Sub ShowConfig(ByRef ConfigObj As Object)<br />
<br />
    ' ShowConfig() function inside my plugin takes in 1 argument, <br />
    ' the reference to an (config) 'object'<br />
<br />
    ' Create args array for the invoke() function, <br />
    ' containing our reference<br />
    Dim args = New Object() {ConfigObj}<br />
<br />
    ' display the Config window <br />
    ' wait for it to close <br />
    pShowConfig.Invoke(tsInterfaceObj, args)<br />
<br />
    ' all done. ConfigObj now points to something interesting<br />
 <br />
    ' actually we're not, args(0) contains the object <br />
    ' we want, not ConfigObj. Therefore make sure<br />
    ' ConfigObj is the correct reference is given back<br />
    ConfigObj = args(0)<br />
<br />
    ' Mmm, this now works!<br />
<br />
 End Sub<br />

I *thought* that if I set args to contain my passed in ConfigObj object, when passing that down into the pShowConfig methodinfo, it would return insided the ConfigObj object passed down (inside the args() array)

BUT

I'm finding that after the .Invoke() method, ConfigObj still references Nothing, but args(0) references the object which is being passed back. Therefore I'm needing to copy the args(0) reference into my ConfigObj variable.

It looks like when I perform the args = {} line, it just create a completely new object, with objects in the array OF TYPES of ConfigObj (Object Type), and not a reference to my ConfigObj Object passed in.

Is this correct?

It doesn't "feel" right....?

any points on this?

This is fundamental stuff, which I'm not getting Frown | :(

Thanks for your help,
Phil.

Re: Help understanding Dim args = New Object() {myObject}

Guffa12-Jun-07 21:21

Guffa

12-Jun-07 21:21

twista wrote:

It looks like when I perform the args = {} line, it just create a completely new object, with objects in the array OF TYPES of ConfigObj (Object Type), and not a reference to my ConfigObj Object passed in.

Is this correct?

Not at all. It creates an array of references to Object with the size of one, and populates it with a reference to ConfigObj.

The method that you are calling is simply not populating the object that you are passing in, it creates a new object and returns it.

---
single minded; short sighted; long gone;

Help with a progress bar

Psycho-^*Coder*-Extreme12-Jun-07 10:54

Psycho-^*Coder*-Extreme

12-Jun-07 10:54

I try to not post many questions here (Google is a programmers best friend) but I thought I might get a better answer here than from a Google search. Here's what I'm trying to do: I have a process (a bulk insert into a SQL 2000 table) where ti could literally insert up to 65,000 rows (depending on how many people we are traveling in any given travel year) and I'm wanting to show some kind of progress meter to the user so they don't think the application's just froze up.

Anyone got any ideas on what is the best process for implementing something like this?

"Okay, I give up: which is NOT a real programming language????"
Michael Bergman

"Well yes, it is an Integer, but it's a metrosexual Integer. For all we know, under all that hair gel it could be a Boolean."
Tom Welch

"Let's face it, the average computer user has the brain of a Spider Monkey."
Bill Gates

nlarson1112-Jun-07 10:59

nlarson11

12-Jun-07 10:59

are you inserting while in a loop or are you doing an insert into from a select statement? if the 2nd choice, then it would make it shard to show progress...

Christian Graus12-Jun-07 11:13

Christian Graus

12-Jun-07 11:13

There's really no way you can track progress, unfortunately, as you're tracking an atomic process in another program.

Xandip12-Jun-07 18:45

Xandip

12-Jun-07 18:45

Psycho-*Coder*-Extreme wrote:
could literally insert up to 65,000 rows

Are you Inserting from within a loop? Or Are you using a Stored Procedure? Please make it clear..
Anyway, if you are doing the DML inside the loop, then there sure is a chance

The name is Sandeep

Psycho-^*Coder*-Extreme22-Jun-07 1:58

Psycho-^*Coder*-Extreme

22-Jun-07 1:58

Iam using a Stored Procedure, but it is an INSERT INTO....SELECT FROM Stored Procedure.

"Okay, I give up: which is NOT a real programming language????"
Michael Bergman

Unbound DataGridView and Checkbox

GoodID21-Jun-07 20:00

GoodID

21-Jun-07 20:00

Hi,

Usually I used image animation like windows when copying file.

GoodID

jadaar12-Jun-07 9:10

jadaar

12-Jun-07 9:10

I am using the DataGridView unbound but now I have need to present boolean information to the user with the DataGridViewCheckBox class. Normally I format a DataTable and populate a datarow into that table like thus as below, but when I add the DataGridViewCheckBoxColum in, I cannot populate the DataTable it has to be inseerted into the grid itself. Any help would be appreciated.

Dim column As New DataGridViewCheckBoxColumn(), rDesc As New DataColumn(), tb as New DataTable
With rDesc
.DataType = System.Type.GetType("System.String")
.ColumnName = "Description"
.Caption = "Description"
.ReadOnly = True
End With
Me.tb.Columns.Add(rDesc)
//Problem Area
With column
.AutoSizeMode = DataGridViewAutoSizeColumnMode.DisplayedCells
.FlatStyle = FlatStyle.Standard
.CellTemplate = New DataGridViewCheckBoxCell()
.CellTemplate.Style.BackColor = Color.Beige
End With

DataGridView1.Columns.Insert(0, column)

Me.DataGridView1.DataSource = tb
Dim r As DataRow
r = tb.NewRow()
r(0) = "hello"
tb.Rows.Add(r)

"I know not with what weapons World War III will be fought, but World War IV will be fought with sticks and stones."

Einstein

Unable to dispose of shared object

mad_cow12-Jun-07 8:14

mad_cow

12-Jun-07 8:14

I can't seem to dispose of a singleton object that my web page has created. Here is the class code:

Public Class Class1
    Implements IDisposable
    Private Shared myInst As Class1
    Private Shared myMutex As New System.Threading.Mutex
    Public Shared myVal As Integer
    Private Shadows disposed As Boolean

    Public Shared Function GetInstance() As Class1
        myMutex.WaitOne()
        If myInst Is Nothing Then
            myInst = New Class1
        End If
        myMutex.ReleaseMutex()
        myInst.myVal += 1
        Return myInst
    End Function

    Public Sub Dispose() Implements IDisposable.Dispose
        If Not disposed Then
            disposed = True
            GC.SuppressFinalize(Me)
        End If
    End Sub

    Public Shared Sub DisposeIt(ByVal Cls1 As Class1)
        Cls1.Dispose()
    End Sub

End Class

In my web form, I have this code:

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As   System.EventArgs) Handles MyBase.Load
    Dim myclass1 As Class1 = Class1.GetInstance
    Class1.DisposeIt(myclass1)
    Response.Write(myclass1.myVal)
End Sub

When I run this program, the object will be created and myVal will be incremented every time the program is run, whether I close the browser beforehand or not. In other words, the "Class1.DisposeIt(myclass1)" statement simply doesn't dispose of the object in memory. I am trying to understand singleton objects and disposing of them, but I am missing some critical concept here. Any help would truly be appreciated.

Guffa12-Jun-07 8:31

Guffa

12-Jun-07 8:31

You have misunderstood the meaning of disposal. To call the Dispose method doesn't remove the object from memory, it's just used to tell the object to prepare for removal. As long as you are holding on to the reference to the object, it will not be garbage collected. As you are not really doing anything in the Dispose method, the object will keep working eventhough Dispose is called repeatedly.

If you want the object to be released, you have to set the reference to Nothing. Then a new object will be created the next time GetInstance is called.

If your object will not contain any unmanaged resources, there is no reason to use the IDisposable interface at all. Just set the reference to Nothing, and the garbage collector will take care of it.

---
single minded; short sighted; long gone;

mad_cow12-Jun-07 8:58

mad_cow

12-Jun-07 8:58

Thanks Guffa, and what you say about setting the reference to Nothing was my original understanding, but it didn't seem to work, which lead to my wrong path down the Dispose lane. Here was my original code from my calling program:

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    Dim myclass1 As Class1 = Class1.GetInstance
    Response.Write(myclass1.myVal)
    myclass1 = Nothing
End Sub

Now, when a person opens his browser, he will see the value "1" displayed on his screen. Open another browser instance, and he will see "2", and so on. Even though the reference was set to nothing, the second browser instance will use the shared value from the object that is supposed to be Nothing. Ok, I can't tell when the garbage collector would have released it from memory, but it seems to me that the second browser instance shouldn't have access to it anyway. So, I am still seem to be stuck with this thing hanging out in memory.

By the way, excuse me, but I think I may have posted this question to the wrong discussion group since this has a bit of a web orientation, but perhaps it applies to workstation applications too.

MidwestLimey12-Jun-07 9:33

MidwestLimey

12-Jun-07 9:33

If your code in Class1.GetInstance() is the same as per your first posting then the reference is being maintained by - Private Shared myInst As Class1 - which will persist as long as the appdomain (process, more or less) does.

Setting a reference to an instance of an object on the heap to nothing only clears that reference. As long as the number of references to a heap object is greater then zero the GC can't collect it.

If each request needs a new object I'm not sure why you are trying to use a singleton approach?

If you only want one per runtime then just call GetInstance() and don't worry about removing it.

If you do need to remove it once in a while, write a method like ...

Public Shared Sub ReleaseInstance()
   myInst = Nothing
End Sub

... and call that.

------------------------------------------------
I'm largely language agnostic -

After a while they all bug me WTF | :WTF:

------------------------------------------------

mad_cow12-Jun-07 9:49

mad_cow

12-Jun-07 9:49

Thanks MidwestLimey, but that doesn't work either. Here is the class now:

Public Class Class1
    Private Shared myInst As Class1
    Private Shared myMutex As New System.Threading.Mutex
    Public Shared myVal As Integer
    Private Shadows disposed As Boolean

    Public Shared Function GetInstance() As Class1
        myMutex.WaitOne()
        If myInst Is Nothing Then
            myInst = New Class1
        End If
        myMutex.ReleaseMutex()
        myInst.myVal += 1
        Return myInst
    End Function


    Public Shared Sub ReleaseInstance()
        myInst = Nothing
    End Sub

End Class

Here is the calling code:

Private Sub Page_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    Dim myclass1 As Class1 = Class1.GetInstance
    Response.Write(myclass1.myVal)
    Class1.ReleaseInstance()
End Sub

Again, if I open this web page, it should kill the object, making any shared variables not accessible to another page that is opened. But, if I open another page, I will see "2" displayed, meaning that it incremented the value from the killed object. I can close all web pages, wait an hour, and if I start another page, I will then see the value "3" displayed. It just stays out there!

I am experimenting with this because I do want a single object in memory, which is to be shared among web pages, but I do want to be able to control when it is disposed of.