Confused by Events - Visual Basic Discussion Boards

Re: VB6 Serial Comm Crashs Visual Studio

Mycroft Holmes1-Sep-09 16:05

1-Sep-09 16:05

STOP throw out what you have started, download VB.net express and start again. You are using a tool that is no longer supported.

Re: VB6 Serial Comm Crashs Visual Studio

Luc Pattyn2-Sep-09 1:11

Luc Pattyn

2-Sep-09 1:11

No matter how obsolete and outdated your chosen language is, Windows always has and always will require you to not touch controls from any thread other than the one that created the control, and my best guess is you are trying to receive and somehow display incoming serial data on a different thread (most asynchronous operations run on some other thread automatically).

This little article[^] describes the problem and solution in .NET (using C# examples); I don't know how it looks in ancient VB.

Smile | :)

Luc Pattyn

Badger | [badger,badger,badger,badger...]

Have a look at my entry for the lean-and-mean competition; please provide comments, feedback, discussion, and don’t forget to vote for it! Thank you.

Calculate the origin and radius of a circle

keithp08231-Sep-09 10:21

keithp0823

1-Sep-09 10:21

My trig skills are lacking, please assist if possible.

Given the coordinates of three points of an arc, how do I calculate the origin and radius of the arc or circle.

Dim s As String() = Split("a 100 100 76 110 50 100", " ")

Dim x1 As Integer = CInt(s(1))
Dim y1 As Integer = CInt(s(2))

Dim x2 As Integer = CInt(s(3))
Dim y2 As Integer = CInt(s(4))

Dim x3 As Integer = CInt(s(5))
Dim y3 As Integer = CInt(s(6))

e.Graphics.DrawArc(Pens.Green, x, y, width, height, angle1, angle2)

Re: Calculate the origin and radius of a circle

Luc Pattyn1-Sep-09 13:58

Luc Pattyn

1-Sep-09 13:58

Hi, this is not a programming question, it is a math question, and as such language independent.
Here is one way to solve it:
- choose two of the three points, and find the line that holds all points at an equal distance of them (that line is perpendicular on the line that connects them).
- choose another set of two of those three points, and find again the line that...
- the center of the circle is bound to be at the intersection of those two lines.

So that is your solution, you can work about the formulae and the code yourself.

Smile | :)

Luc Pattyn

Have a look at my entry for the lean-and-mean competition; please provide comments, feedback, discussion, and don’t forget to vote for it! Thank you.

Re: Calculate the origin and radius of a circle

keithp08232-Sep-09 5:35

keithp0823

2-Sep-09 5:35

Yes, it is a math question... which is why I stated that my trigonometry skills are lacking. If I knew the formulas to do as you suggested, I wouldn't be asking the question to begin with. I do; however, appreciate the feedback.

I am researching the math, but don't have a lot of time to come up with the solution. If anyone can help by showing me the correct formula to use I would very much appreciate the assistance.

Re: Calculate the origin and radius of a circle

Luc Pattyn2-Sep-09 5:54

Luc Pattyn

2-Sep-09 5:54

oh nice. so you are one-voting me and asking to be spoon fed at the same time?

I have news for you: this is not a hand-me-the-code kind of site, this is a site for serious people making and showing an effort and asking for help when they get stuck in the middle of it; or alternatively asking for general advice (which I gave you) before starting something.

And to all people that don't have the time, my advice is to either work harder or start earlier, or both. I'm not impressed.

Dead | X|

Luc Pattyn

Have a look at my entry for the lean-and-mean competition; please provide comments, feedback, discussion, and don’t forget to vote for it! Thank you.

Re: Calculate the origin and radius of a circle

keithp08232-Sep-09 6:32

keithp0823

2-Sep-09 6:32

I'm not asking to be spoon fed the code. Just asking if anyone knows the formula.

Yes, I'm also searching with google and I'm already working through some trig tutorials to figure out the math. Now, if you will stop wasting time by posting non-answers, I'll get back to my research.

Confused by Events

Sonhospa1-Sep-09 1:49

Sonhospa

1-Sep-09 1:49

Hello everybody,

in my project I have a pictureBox, sitting in one of the panels of a SplitContainer and docking to it in fill mode. The PictureBox loads it's images in zoom mode and is supposed to take the size of the loaded/zoomed image automatically whenever a) the form's size is changed or b) the splitter is moved.

In a first approach to reach this I call

Private Sub FitPictureBox()
    If PictureBox1.Image IsNot Nothing Then
        Dim thisFrame As Bitmap = PictureBox1.Image
        AspectRatio = thisFrame.Width / thisFrame.Height
        SplitContainer3.SplitterDistance = PictureBox1.Width / AspectRatio
    End If

from the 'resize' event as well as from the 'splitter.moved' event.

Now I'm desperately struggling to make this work, coz the 'resize' event (as well as the layout event) calling 'FitPictureBox' triggers the 'splitter.moved' event again - and I run into a loop i.e. a 'stack overflow' exception. Still I need to consider fitting the PictureBox in both cases.

Could anyone of you please guide me a way out of this dilemma? Did I use the wrong events or is there a better approach at all?

Thank you,
Mick

Re: Confused by Events

Jay Royall1-Sep-09 2:02

Jay Royall

1-Sep-09 2:02

Hi, I have also had similar problems in the past with events causing other events to fire. I have found a way around this but really don't think it is the best way, so it will be interesting for me also to see other people's responses.

What I have done in the past is set a global variable and check that variable in the event handlers. So, at the start of your 'resize' event set a variable, say 'Resizing' to True, then in your splitter.moved event, check the state of 'Resizing', if False then do the event. Just remember to set 'Resizing' back to nothing at the end of the 'Resize' event.

Like I said, I don't think this is the best solution, seems a little dirty to me but it works.

Re: Confused by Events

Mycroft Holmes1-Sep-09 16:09

Mycroft Holmes

1-Sep-09 16:09

Liqz wrote:
so it will be interesting for me also to see other people's responses

Nope - this is exactly the method I use, form level booleans called bLoading sprinkled throughout the app.

Re: Confused by Events

Jay Royall1-Sep-09 22:07

Jay Royall

1-Sep-09 22:07

Ah OK fine. I just thought that I might have been missing something native to the .Net framework which does a similar job. But thanks for the reassurance, I shall be more confident in my approach in the future Big Grin | :-D

Re: Confused by Events

Johan Hakkesteegt1-Sep-09 2:06

Johan Hakkesteegt

1-Sep-09 2:06

If I understand you correctly, the picuterbox is supposed to fit itself to the size of the SplitContainer after the container's size is changed (in whatever way).

Can you do something like this?
1. the container size changes
2. measure the size of the container
3. measure the size of the picturebox
4. if the picturebox's size is (already) correct, do nothing; if it is incorrect call your sub (and do whatever else).

Or what Liqz said...

My advice is free, and you may get what you paid for.

Re: Confused by Events

Sonhospa1-Sep-09 2:35

Sonhospa

1-Sep-09 2:35

Wow - I didn't expect such quick responses Big Grin | :-D

Thank you both for the ideas!

@Liqz: that's exactly what I tried since I posted. Somehow it seems that the events are fired not only once - so when resetting the flag variable (just by chance Wink | ;)

I had also called it 'resizing') back to FALSE at the end of the 'resize' event, the problem arises again when it fires a second time...

@Johan:
I don't exactly know the sequence of the different events - resizing of the form might trigger the resize event for a main SplitContainer I have in it AND the resize event of a second SplitContainer which then holds the PictureBox. Do you probably know a way how to find out which event exactly fired my sub?

Resolved: Confused by Events

Sonhospa1-Sep-09 3:19

Sonhospa

1-Sep-09 3:19

Liqz's approach finally worked out well for me after changing the last line in my sub to SplitContainer3.SplitterDistance = SplitContainer3.Width / AspectRatio

It seems as if the dependency between the SplitterDistance and the size of the PictureBox set some built-in event-devils free WTF | :WTF:

Thank you both Thumbs Up | :thumbsup:

Re: Resolved: Confused by Events

Jay Royall1-Sep-09 3:31

Jay Royall

1-Sep-09 3:31

You're welcome, glad I could be of assistance Smile | :)

Help with IE automation through VBA(Excel)

adityabaraya31-Aug-09 20:27

adityabaraya

31-Aug-09 20:27

The following code is probably the most common code on the net for automating IE with Excel.
Sadly when I use it I get an automation error stating "Method Busy of IWebBrowser2 failed" (The Bold Part)...
Can anybody help me out how to tackle this error?

Sub Button1_Click
Set myIE = CreateObject("InternetExplorer.Application") 'New '
Dim myURL As String
Dim strSearch As String
'Set starting URL and search string
myURL = "http://google.com"
strSearch = "Infosys"
'Make IE navigate to the URL and make browser visible
myIE.Navigate myURL
myIE.Visible = True
'Wait for the page to load
Do While myIE.Busy Or myIE.ReadyState <> READYSTATE_COMPLETE
DoEvents
Loop
'Set IE document into object
Set myDoc = myIE.Document
'Enter search string on form

myDoc.forms(0).q.Value = strSearch

'Submit form
myDoc.f.submit

'Wait for the page to load
Do While myIE.Busy Or myIE.ReadyState <> READYSTATE_COMPLETE
DoEvents
Loop
'MsgBox myIE.LocationName

End Sub

How to load a word document and save it into sql db?

waner michaud31-Aug-09 8:28

waner michaud

31-Aug-09 8:28

Hi,

I am trying to load a word doc and save it into a table.
I have a column for the file document as type image in the table.
when i doubleclick to select the file it throws an exception because the file type .

dim docs as system.drawing.image
me.openfiledialog.showdialog()

docs=system.drawing.bitmap.fromsream(me.openfiledialog.Openfile,true)
me.PicturePictureBox.image=docs

Guide me please

Thanks : Unsure | :~

Re: How to load a word document and save it into sql db?

Steven J Jowett31-Aug-09 8:40

Steven J Jowett

31-Aug-09 8:40

The error is due to the Word document not being an image file, such as a Bitmap or JPEG. Don't confuss a SQL Image type as a picture. Search Google on BLOBs

Steve Jowett
-------------------------
Real programmers don't comment their code. If it was hard to write, it should be hard to read.

Re: How to load a word document and save it into sql db?

waner michaud31-Aug-09 8:46

waner michaud

31-Aug-09 8:46

Thanks for repling..
I agree but I am not getting a good result on the search from google..
the word document is binary type or bites..
the file is from filestream..
so where lies my problem in getting the right type

thanks

Re: How to load a word document and save it into sql db?

Dave Kreskowiak31-Aug-09 9:07

Dave Kreskowiak

31-Aug-09 9:07

Why are you even bothering with creating an Image object with a Word document?? The Image class is for handling, well, picture, .BMP, .JPG, .PNG files... not Word documents.

After seeing code like this, I'm quite sure you've got a mountain of other things wrong, so without seeing the code that you're using to setup the SQL INSERT operation, it's impossible to tell you where you went wrong.

A guide to posting questions on CodeProject[^]

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007, 2008
But no longer in 2009...

Re: How to load a word document and save it into sql db?

waner michaud31-Aug-09 9:20

waner michaud

31-Aug-09 9:20

Thanks,
let's do away with my initial coding.
what I want to accomplish in a form is to be able to upload .doc, text, rtf, pgf files and save it to a table..
Upload() will load the document from the file path and put the path into a richtextbox and save it in a table.

viewdocumentclick() will read the document in its format.

Hope I am a bit clearer now..

Thanks alot

Re: How to load a word document and save it into sql db?

Dave Kreskowiak31-Aug-09 9:53

Dave Kreskowiak

31-Aug-09 9:53

All you're doing is saving a stream of bytes to the database, just like saving an image file. Every file is nothing but a stream of bytes.

' This is array is holding the contents of your file.
Dim fileContents() As Byte
.
.
.
myConnection = New SqlConnection(CONNECTION_STRING)
Dim myCommand As New SqlCommand("INSERT INTO someTable (FileData) VALUES (@Image)", myConnection)
Dim myParameter As New SqlParameter("@Image", SqlDbType.Image, fileContents.Length)
myParameter.Value = fileContents
myCommand.Parameters.Add(myParameter)
myConnection.Open()
myCommand.ExecuteNonQuery()

A guide to posting questions on CodeProject[^]

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007, 2008
But no longer in 2009...

Re: How to load a word document and save it into sql db?

waner michaud31-Aug-09 10:15

waner michaud

31-Aug-09 10:15

Thanks again,
I am using Vb.net(Visual Studio) and SqlExpress where I am using Dataset and TableAdapter.

I just need to click on a command to open the directory, select the file and load it or the path of it into the richtextbox and the savecommand_click() save everything..

On read, readcommand_click() read the file in its format and not being able to edit the document.

thanks

Re: How to load a word document and save it into sql db?

Dave Kreskowiak31-Aug-09 12:42

Dave Kreskowiak

31-Aug-09 12:42

...and...so, what's the question? I just showed you how to save data to an SQL Server. I have no idea what you're asking now...

A guide to posting questions on CodeProject[^]

Dave Kreskowiak
Microsoft MVP
Visual Developer - Visual Basic
2006, 2007, 2008
But no longer in 2009...

Re: How to load a word document and save it into sql db?

waner michaud1-Sep-09 3:18

waner michaud

1-Sep-09 3:18

Hi Dave,

The question is not actually saving the information. My question is how to open the folder, retrieve .doc, .txt file, like you will do with an image.

thanks

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