Multi Threading Optimal Use? - Visual Basic Discussion Boards

Sending information to and from different forms

Emile Jacobs8-Jul-03 9:20

8-Jul-03 9:20

I am currently developing a system as a project for an university subject but is struggeling with something that is affecting everything in the system. I have an open form, where you enter information on a school / university. On the form you click on a button to register a contact person for that school / university. This button opens another form (the contact person form). After completing all the necessary contact's information and close the form, the contact person's name, surname and telephone must be showed in the previous form.

How on earth do you send the information from the contact form to the previous form (that is still open)?????

Can anybody help me?!? This is very important, for my whole project depends on this!!! Cry | :((

Re: Sending information to and from different forms

dynamic8-Jul-03 9:53

dynamic

8-Jul-03 9:53

try this :
In Form1:

<font color="blue">Private</font><font color="blue"></font> <font color="blue">Sub</font> Button1_Click(<font color="blue">ByVal</font> sender <font color="blue">As</font> System.Object,<font color="blue"></font> <font color="blue">ByVal</font> e <font color="blue">As</font> System.EventArgs) <font color="blue">Handles</font> Button1.Click <br> <font color="blue"></font><font color="blue"></font>    <font color="blue">Dim</font> frm2 <font color="blue">As</font> <font color="blue">New</font> Form2() <br> <font color="blue"></font><font color="blue"></font>    Me.AddOwnedForm(frm2) <font color="DarkGreen">'/// add it as an owned form. <br></font><br> <font color="blue"></font><font color="blue"></font>    frm2.Show() <font color="DarkGreen">'/// show it. <br></font><br> <font color="blue">End</font><font color="blue"></font> <font color="blue">Sub</font> <br>

In Form2:

<font color="blue">Private</font><font color="blue"></font> <font color="blue">Sub</font> Button1_Click(<font color="blue">ByVal</font> sender <font color="blue">As</font> System.Object,<font color="blue"></font> <font color="blue">ByVal</font> e <font color="blue">As</font> System.EventArgs) <font color="blue">Handles</font> Button1.Click <br> <font color="blue"></font><font color="blue"></font>    <font color="blue">Dim</font> frm1 <font color="blue">As</font> Form1 = Me.Owner <br> <font color="blue"></font><font color="blue"></font>    frm1.TextBox1.AppendText("some text from Form2 , to Form1!") <br> <font color="blue">End</font><font color="blue"></font> <font color="blue">Sub</font> <br>

hope it helps Smile | :)

Vb:

<font color="blue">Public Function</font> TwinsOnWay(<font color="blue">ByVal</font> twins <font color="blue">As String</font>) <font color="blue">As String <br>     Select Case</font> twins<br>         <font color="blue">Case</font> "Gender" <br>             <font color="blue">Return</font> "Two Girls" <br>     <font color="blue">End Select <br> End Function</font> <br>

Re: Sending information to and from different forms

Emile Jacobs8-Jul-03 23:45

Emile Jacobs

8-Jul-03 23:45

Thanx A LOT!!! I am going to try it! I knew the answer is easy, but you know how it goes - one always looks for the most difficult solution...

Good luck with the twins...

If I can't get it to work, you will hear from me again... Cool | :cool:

How to make VB ActiveX DLL?

mr20038-Jul-03 9:19

mr2003

8-Jul-03 9:19

Hi
I would like to use a certain VB functions in Vc++.
It was recommended to me to make an ActiveX DLL in VB, and call VB ActiveX DLL in VC.

How can I make a VB ActiveX DLL?

Ehsan Behboudi

Re: How to make VB ActiveX DLL?

Hesham Amin8-Jul-03 20:45

Hesham Amin

8-Jul-03 20:45

start a new project ..
choose ActiveX DLL
in the project add Class modules with functions , propertties you need..
then build the project.
is this all waht you need ?

Re: How to make VB ActiveX DLL?

mr20039-Jul-03 2:49

mr2003

9-Jul-03 2:49

So, I should make an ActiveX Dll project and add all the functions/constants to it, then build it?
how can I use the functions in my VC++ program.
should I just type the functions down in the VB, how can I add them?

Ehsan Behboudi

Re: How to make VB ActiveX DLL?

Hesham Amin9-Jul-03 3:45

Hesham Amin

9-Jul-03 3:45

Hi,,
using it in VC++ is a long story Smile | :)

in brief look MSDN for CoCreateInstance
you can add functions , properties to the VB6 project :
choose Tools menu then Add Procedure

Multi Threading Optimal Use?

rlcc8-Jul-03 4:14

rlcc

8-Jul-03 4:14

I am using multithreading in a program, but since I have never done so before I have some questions as to optimal use. Take the following example:

I have an COM object lets call it "comObj" which has a function "SendData". Since the program operates under heavy volume calling "Senddata" concurrently on seperate threads is desirable.

So now my question, if I call the same function on the same object in multiple threads will I really experience a performance gain? Or do I have to create multiple objects (created inside thread) to see a performace gain?

code:
[code]
'...in some function
Dim comObj as (whatever object)

'these are passed by reference
Dim mySend1 as new OutThread(comObj)
Dim mySend2 as New OutThread(comObj)

'...destroy objects...

Public MustInherit Class ThreadWrap
' i use a threadwrapper because multiple thread subtypes
Protected m_Thread As Thread

Public Sub New()
m_Thread = New Thread(AddressOf run)
End Sub

Public Sub start()
Me.m_Thread.Start()
End Sub

Public MustOverride Sub run()

End Class

Public Class OutThread
Inherits ThreadWrap
dim m_objCom as object

Public Sub New(ByRef comObj As Object)
m_Thread = New Thread(AddressOf run)
m_objCom = comObj
End Sub

Public Overrides Sub run()
'this is the sameobject used in both threads
m_comObj.SendData
End Sub

End Class
[/code]

Now the alternitive I see would be to not delcare your object first and then create and destroy it inside the Run() function, but that would require twice as many calls to the constructor and destructor, plus of course more overall memory.

So logically I would hope the method above does utilize multiple threads, but do all threads have to wait on that one object and does that create a bottle neck? Any clarification would be great thanks.

~rlcc

Re: Multi Threading Optimal Use?

Daniel Turini8-Jul-03 10:25

Daniel Turini

8-Jul-03 10:25

Multiple threads will generally give you gains over single thread on these situations:

1. More responsive UI;
2. There's something the CPU could be doing while it's waiting for an I/O operation;
3. You have multiple CPUs;
4. You have a Pentium 4 with HyperThreading, on some specific situations;

Notice that you won't have CPU gains, actually, as you've noticed, you will spend more CPU to do real parallel work; so, the general rule is only to MT if your CPU is waiting for something.

ORACLE One Real A$#h%le Called Lary Ellison

How to Get \ Set The size of one col?

lee12128-Jul-03 3:55

lee1212

8-Jul-03 3:55

Hi How can i get the width of a col in a datagrid? Mad | :mad:

how to perform that...

elmahdy7-Jul-03 13:41

elmahdy

7-Jul-03 13:41

how to get sounds effects to my programin VB6
example : when i press a button a song plays and so on
BUT without running its program(winamp,windows media player,...etc)
please reply to me

ahmed

ahmed elmahdy

Re: how to perform that...

J. Dunlap7-Jul-03 13:46

J. Dunlap

7-Jul-03 13:46

Use the sndPlaySound[^] API. Smile | :)

"Blessed are the peacemakers, for they shall be called sons of God." - Jesus

"You must be the change you wish to see in the world." - Mahatma Gandhi

outlook style interface

yan194547-Jul-03 8:00

yan19454

7-Jul-03 8:00

Do you know how to create outlook style interface ? Thanks.

Frances

Re: outlook style interface

apferreira8-Jul-03 6:04

apferreira

8-Jul-03 6:04

Easy. Just combine several pannels and splitters and use the docking property.

System.IO.DirectoryInfo.GetFiles.Getlength

DxSolo7-Jul-03 6:41

DxSolo

7-Jul-03 6:41

i am trying to get the number of files returned when you use the getfiles function so i dont have to run through them first. the getlegth part accepts a parameter called dimension which is a zero based array but i dont know what to give it any help would be much appreciated

Re: System.IO.DirectoryInfo.GetFiles.Getlength

Mike Dimmick7-Jul-03 6:53

Mike Dimmick

7-Jul-03 6:53

System.IO.DirectoryInfo.GetFiles() returns an array of FileInfo. You should be able to use the Length property of the array to find out how many there are.

GetLength() is for multi-dimensional arrays; you can specify 0 for the dimension to get the length of a single-dimension array.

--
Mike Dimmick

WinForms DataGrid - colors and selecting individual cells

IainJ7-Jul-03 3:58

IainJ

7-Jul-03 3:58

Hi, Can anyone tell me if it's possible to set the foreground and/or background colors of individual cells in the Window Forms DataGrid control ? Also, is it possible to allow the user to select more than one cell at a time ? If so, some example code (ideally VB.NET) would be brilliant Smile | :)

I have to create a 'booking calendar' type grid showing provisional and confirmed bookings in different colours and I'd like to allow the user to click & hold and move (drag) the mouse to book a week or a variable number of days.

Alternatively, does anyone know of a better suited grid control that could handle such a use ? Previously (in VB6) I Used the FlexGrid control for vaguely similar uses, but that control doesn't seem to exist in .NET.

Many thanks.

Iain.

Re: WinForms DataGrid - colors and selecting individual cells

dynamic8-Jul-03 2:03

dynamic

8-Jul-03 2:03

you can still use a flexigrid in .net , just right click on your toolbox and click "Customise toolbox" , on the window that opens, choose "COMM" and then you will find the flexigrid control in that list, it will be added to your toolbox and you can then use it as before in vb6.

Vb:

<font color="blue">Public Function</font> TwinsOnWay(<font color="blue">ByVal</font> twins <font color="blue">As String</font>) <font color="blue">As String <br>     Select Case</font> twins<br>         <font color="blue">Case</font> "Gender" <br>             <font color="blue">Return</font> "Two Girls" <br>     <font color="blue">End Select <br> End Function</font> <br>

Deployment problem...

-- NA --6-Jul-03 23:36

-- NA --

6-Jul-03 23:36

I have a project in VB6, an accounting package, that is so far working perfectly. The only problem now is deployment Dead | X|

In a nutshell: at the moment I'm using NSIS[^], which (I thought) was working fine for me. The only problem is that when the program is installed on a machine that doesn't have VS installed, it refuses to work. The reason for this is that it's missing runtimes. I've tried packaging the VBRun60sp4.exe[^] file, but that also doesn't seem to help. As a last resort I've tried using the P&D Wizard, which auto-updates system files, but all it does is updates the files, asks for a reboot, when rebooted I try it again, and the same thing happens: it 'installs' system files and asks for a reboot again Mad | :mad:

Please help Confused | :confused:

Paul

Live in such a way that you would not be ashamed to sell your parrot to the town gossip. - Will Rogers

modified 18-Jul-18 11:59am.

Re: Deployment problem...

-- NA --7-Jul-03 0:34

-- NA --

7-Jul-03 0:34

Solved.

Paul Wink | ;)

Live in such a way that you would not be ashamed to sell your parrot to the town gossip. - Will Rogers

modified 18-Jul-18 11:59am.

reading xml files using recordset

r i s h a b h s6-Jul-03 19:05

r i s h a b h s

6-Jul-03 19:05

how do i read xml files using adodb
is there any odbc-driver available

can someone direct me to some samples

thanx

rIsHaBH

Re: reading xml files using recordset

Hesham Amin6-Jul-03 21:45

Hesham Amin

6-Jul-03 21:45

rs.Open "FilePath",con,,,adCmdFile
where:
rs:the name of the recordset object
con:active connection

ContextMenu & TextBox

almigrp5-Jul-03 1:24

almigrp

5-Jul-03 1:24

Hi,

I have a very "simple" problem, but i dont know how to sove it. I want to show a contextmenu, where one menu item is a textbox (ex. Right click on a cell of a open access table in access).
Can anyone help me?

almigrp (Misel)

Developing Excel Add-In using VB.NET

AlfredoDS4-Jul-03 2:32

AlfredoDS

4-Jul-03 2:32

Hello,

how can I create a VB.NET project who add features (as add-in for example) to Excel ?

Best Regards

Alfredo DS

Alfredo DS

Re: Developing Excel Add-In using VB.NET

apferreira8-Jul-03 6:06

apferreira

8-Jul-03 6:06

For Office 10 use the Office Primary Interop Assemblies provided by Microsoft.

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.