Re: REfresging Form While process is running - C# Discussion Boards

9-Jun-08 23:57

Hi Guys. I have read in a few post about this but for the life of me I can't find any of them and have tried searching the posts about this but don't get any results returned.

I have an application that reads data and writes that data to an Excel sheet. Problem I have is that when I change to another application while the process is running and return to the form it just shows a blank white form with just the progressbar and percentage updating.

Now, I know I can put the other process into a sepperate Thread but that means me chasnging the whole layout of my application as the work is done in a button even.

Is there any other way I can get the form to refresh and to show me the form properly?

Thanks in advance.

Excellence is doing ordinary things extraordinarily well.

Giorgi Dalakishvili10-Jun-08 0:12

10-Jun-08 0:12

Yes there is but I wouldn't recommend it. You should put long running process in a separate thread and not in a button click event for several reasons. It will make your GUI responsive, the code will be designed and structured in much more better way.

Giorgi Dalakishvili

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MumbleB10-Jun-08 1:44

10-Jun-08 1:44

So, basically without re-working the whole app there is no chance?

Just to clarify, I have been reading up on Threads and from what I read it doesn't seem to be that easy to work with but it doesn't seem that diffcult though. So, I would just have to declare a new Thread, call this Thread in the button event and away it goes?

I'll try and move the stuff around a bit to see what I can do about this. Hopefully I get it to work with no hastles.

Thanks mate for the reply

Excellence is doing ordinary things extraordinarily well.

Giorgi Dalakishvili10-Jun-08 1:56

10-Jun-08 1:56

Kwagga wrote:
So, basically without re-working the whole app there is no chance?

You can use Application.DoEvents() but I would highly discourage from doing so.

Kwagga wrote:
Just to clarify, I have been reading up on Threads and from what I read it doesn't seem to be that easy to work with but it doesn't seem that diffcult though. So, I would just have to declare a new Thread, call this Thread in the button event and away it goes?

Threads aren't very easy topic but they are quite powerful and it's worth studying it. If you need to do simple work you can use BackgroundWorker class. Here is a more in depth explanation about threading concepts: Threading in C#[^]

Giorgi Dalakishvili

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MumbleB10-Jun-08 5:44

Re: REfresging Form While process is running [modified]

10-Jun-08 5:44

Hi Giorgi. I ahve moved the code into a new thred but I get an error on the progressbar. Error details as below.

System.InvalidOperationException was unhandled<br />
  Message="Cross-thread operation not valid: Control 'progressBar1' accessed from a thread other than the thread it was created on."<br />
  Source="System.Windows.Forms"<br />
  StackTrace:<br />
       at System.Windows.Forms.Control.get_Handle()<br />
       at System.Windows.Forms.Control.SendMessage(Int32 msg, Int32 wparam, Int32 lparam)<br />
       at System.Windows.Forms.ProgressBar.set_Maximum(Int32 value)<br />
       at NomConv.Form1.RunExcel() in C:\Documents and Settings\mumbleb\My Documents\Visual Studio 2008\Projects\NomConv\NomConv\Form1.cs:line 118<br />
       at System.Threading.ThreadHelper.ThreadStart_Context(Object state)<br />
       at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)<br />
       at System.Threading.ThreadHelper.ThreadStart()<br />
  InnerException:

Now, this is what I'm doing. I'm calling the Thread in the button event as below.

        private void btnRun_Click(object sender, EventArgs e)
        {
            Thread excelrun = new Thread(RunExcel);
            excelrun.Start();
            //Set up the ProgressBar Properties

            lblPercent2.Visible = true;
            lblRecordProcessed.Visible = true;
            lblProgText.Visible = true;
            progressBar1.Visible = true;
            lblProgress.Visible = true;
}

And then the code from the new class.

private void RunExcel()
{
    string filepath;
    filepath = txtboxSelectTxtFile.Text;
    FileHelperEngine<ReadFile> engine = new FileHelperEngine<ReadFile>();
    engine.ErrorManager.ErrorMode = ErrorMode.SaveAndContinue;

    ReadFile[] res = engine.ReadFile(filepath, 1);
    ReadFile[] mes = engine.ReadFile(filepath);

    //Progress Bar stuff was here
    int progrval = 0;
    progrval = progressBar1.Value;
    progressBar1.Minimum = 0;
    progressBar1.Maximum = engine.TotalRecords;

Any idea what I should do? I have tried moving the code for the progressbar around and I get all sorts of errors on it.

Excellence is doing ordinary things extraordinarily well.

Giorgi Dalakishvili10-Jun-08 6:03

10-Jun-08 6:03

You can't access controls from another threads. To manipulate them from other thread use Invoke method of ProgressBar class.

Giorgi Dalakishvili

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modified on Tuesday, June 10, 2008 12:22 PM

MumbleB10-Jun-08 7:07

10-Jun-08 7:07

Think I have found an article that explains exactly what to do.

http://www.dreamincode.net/forums/blog/martyr2/index.php?showentry=680[^]

Excellence is doing ordinary things extraordinarily well.

Giorgi Dalakishvili10-Jun-08 7:35

problem with output parameter

10-Jun-08 7:35

Yes that is one of the possible solutions.

Giorgi Dalakishvili

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Splash Screen Form

see_seA9-Jun-08 23:57

see_seA

9-Jun-08 23:57

I'm trying to make a splash screen with the following requirements:
1) Must fade in and fade out (issues)
2) Fades in before main program form is open and fades out once it is (done this)
3) Displays an image which is not squash and has transparency (issues)

So I've looked on the net and I'm still struggling with some aspects if anyone can assist. Fading the form is trivial (by setting the Opacity), however getting a form to be transparent (to work with the pictures transparency) and then fading that in and out is a mess.

I have tried numerous methods, such as overriding OnPaintBackground, changing the style of a form to allow a transparent background and a few other things. The problems I hit are:
- When fading the transparent form, by changing the Opacity the transparent bits turn black
- When the splash screen first shows it paints properly, but when the main form is finally loaded the transparent bits of the splash screen still show what was there before the form loaded (i.e. not repainting or something).

At the moment some of the code I have looks like this:

protected override void OnPaint(PaintEventArgs e)
{
    // Do nothing here!
}

protected override void OnPaintBackground(PaintEventArgs e)
{
    Console.WriteLine("paintBackground");
    Graphics gfx = e.Graphics;
    gfx.DrawImage(global::DesktopLiveDotNet.Properties.Resources.splash_screen, new Rectangle(0, 0, Width, Height));
}

But when it starts to fade the transparency turns black:

private void timer1_Tick(object sender, EventArgs e)
{
    Opacity = fOpacity / 100;

    Application.DoEvents();
    fOpacity -= StepVal;

    if (fOpacity <= 0)
    {
        timer1.Stop();
        Close();
    }
}

Not quite sure how to proceed and any ideas would be great! Smile | :)

Re: Splash Screen Form

leppie10-Jun-08 23:46

leppie

10-Jun-08 23:46

I have never been able to use BackGroundpainting successfully. Why not just paint normally?

xacc.ide - now with TabsToSpaces support
IronScheme - 1.0 alpha 4a out now (29 May 2008)

Re: Splash Screen Form

see_seA11-Jun-08 0:02

see_seA

11-Jun-08 0:02

I've tried that.

My problem is making the form's background disappear. I cannot get rid of the grey square (default form background color). So to do that I override the paintbackground method but that then draws black wherever the transparency is meant to be. Whether double buffered or not. It definitely draws black in the transparency when changing Opacity :/

Mr.Kode9-Jun-08 23:50

Mr.Kode

9-Jun-08 23:50

i have stored procedure with two parameters as follows:
create procedure checkCompatability
(
@compatility varchar output,
@award_num int
)
AS
SET NOCOUNT OFF;
IF EXISTS (SELECT Award_num from table1 where award_num=@award_num)
begin
set @compatability='Y'
print @compatability
end
else
set @compatability='N'
print @compatability
GO

in C# parameters:

SqlCommand checkDone = new SqlCommand();
checkDone.Connection = con1;
checkDone.Connection.Open();
checkDone.CommandType = CommandType.StoredProcedure;
checkDone.CommandText = "checkCompatability";

SqlParameter comp = new SqlParameter("@compatability", SqlDbType.VarChar);

string S = comp.Value.ToString();\\null reference exception occours here
lblresult.Text = S.ToString();
comp.Direction = ParameterDirection.Output;

SqlParameter complete = new SqlParameter("@award_num", SqlDbType.Int);
complete.Direction = ParameterDirection.Input;
int awN = int.Parse(comboAwardNum.Text);
complete.Value =(int) awN;

lblresult.Text = comp.Value.ToString();

checkDone.Parameters.Add(comp);
checkDone.Parameters.Add(complete);

checkDone.ExecuteNonQuery();
checkDone.Connection.Close();

what is the problem with that code?

Re: problem with output parameter

Ashfield10-Jun-08 1:25

Ashfield

10-Jun-08 1:25

Mr.Kode wrote:
what is the problem with that code?

I give up. What is the problem?

Bob
Ashfield Consultants Ltd

Re: problem with output parameter

Eslam Afifi10-Jun-08 2:30

Eslam Afifi

10-Jun-08 2:30

http://www.codeproject.com/script/Forums/View.aspx?fid=1649&msg=2589045 Mad | :mad:

Eslam Afifi

Adding VB Code to ThisWorkbook using C# problem

Yasser Sobhdel9-Jun-08 23:26

Yasser Sobhdel

9-Jun-08 23:26

Hi
I am trying to add Some code to ThisWorkbook in Excel file before opening it using C# but I can't.Can any body please tell me what to do?
the code looks like this:

Private Sub Workbook_Activate()
Application.CutCopyMode = False
Application.OnKey "^c", ""
Application.CellDragAndDrop = False
End Sub

By the way I don't want to add this code in a standard module ,just in Thisworkbook.
thanks

[I am using VS 2008 and MS Office 2003]

my code looks like this but it adds to the Standard Module not ThisWorkBook:
Microsoft.Vbe.Interop.VBComponent oModule;
oModule = Excel_WorkBook.VBProject.VBComponents.Add(Microsoft.Vbe.Interop.vbext_ComponentType.vbext_ct_StdModule);
oModule.CodeModule.AddFromString("My Function Text");

Byte[] type in datagrid gives error.

topcatalpha9-Jun-08 23:08

topcatalpha

9-Jun-08 23:08

Hi,

I'm storing data (not image) in my SQL database as a type varbinary.
Retrieving this table in a dataset.
With databinding i bind the datagrid to the dataset.
But the datagrid gives an error because it tries to convert byte[] to image (i guess.)

The columns are not persistent (predefined)

Anyone an idea how i can solve this ?

thx

kurt

Fetching files

shriya_179-Jun-08 23:04

shriya_17

9-Jun-08 23:04

Hi!
I am stuck in my approach.
I need to fetch files present in a folder with "day" and "year" (2, 2008) as parameter.
i need code for it. As of now i am able to fetch all the files present in the folder but am not able to fetch according to date. If anyone can help me, Thnx

Re: Fetching files

Ashfield9-Jun-08 23:28

Ashfield

9-Jun-08 23:28

Have a look at System.IO.File.GetCreationTime (or GetLastWriteTime), see if that will give you what you need.

Bob
Ashfield Consultants Ltd

Get filename from windows explorer right menu?

Abdul Gafoor9-Jun-08 22:39

Abdul Gafoor

9-Jun-08 22:39

Hi,

I would like to fetch the filename(with complete path) from windows explorer right menu?
please guide me.

Re: Get filename from windows explorer right menu?

Giorgi Dalakishvili9-Jun-08 22:45