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Hello,
Can any body tell me how to read and write a text file in VB.Net
Thanks in advance,
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Hi,
i have made a form which follows the following logic :-
The form displays various panels which are used to get criterias from the user. then form.layout is suspended and the following algorithm executes :
1. Based on these criterias i add various column to a datatable say dtRecordsReturned.
2. Then datagridcolumnstyles [some of them are instances of classes i inherited from datagridcolumnstyle] are made and added to a datagridtablestyle , which is then added to the TableStyle property of a datagrid say dgRecordsReturned.
3. the dtRecordsReturned is then bound to a dataview dvRecordsReturned.
4. dvRecordsReturned is bound to the dgRecordsReturned.
5. then records(rows) are added to dtRecordsReturned by executing a sqlQuery.
6. Then Values of some of the columns of each row are set according to the criterias got from the user. While doing this some special conditions may arise, which i am displaying to the user by setting an errormessage on that particulare column by calling .SetColumnError(columnname,strSpecialContidionDescription).
7. then the panel [pnlRecordsReturned] which contains dgRecordsReturned is brought to the front by calling pnlRecordsReturned.BringToFront().
8.Finally the form.Resumelayout() is called.
Now the Problem i am facing is that though the ColumnErrorIcon is displayed in the columns, no tooltip message pops up when the cursor is hovered over the icon.
I tried using .RowError instead of .SetColumnError still the result is similar. ErrorIcon appears in the rowheader but no tooltip message pops up.
Any Suggestions?
Thanks
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hiya, i am new to .NET.I am required to use .NET to do my project. Hope the people here can help me the following questions.
1:When begin,what codes should i added first?
2:What is the code for the link control from a web form to another?
3:How to connect to microsoft access?
4:How to make the buttons to scroll the info?
5:How to make the data to be read according to the link topic under the same database?
Thanks
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Wow...
rei ayumi wrote: 1:When begin,what codes should i added first?
....
rei ayumi wrote: 2:What is the code for the link control from a web form to another?
<a href="page2.aspx">Goto Page 2</a>
<asp:hyperlink id="Page2Link" runat="server" navigateurl="page2.aspx" />
rei ayumi wrote: 3:How to connect to microsoft access?
4:How to make the buttons to scroll the info?
5:How to make the data to be read according to the link topic under the same database?
Seems to me you don't even know the basics... I'd suggest you get a book...or 12....and read some tutorials, or follow by example, lots of great code on this site.
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rei ayumi wrote: 1:When begin,what codes should i added first?
Whichever you think should be added first! Given you question it seems you are a begginer, I would suggest writing a small part of the UI and use that to get data out.
rei ayumi wrote: 2:What is the code for the link control from a web form to another?
Not sure what you mean by this!
rei ayumi wrote: 3:How to connect to microsoft access?
You need to research a technology called ADO.NET: it is built into the .net framwork and provides a way of connecting to most common databases. You might also want to google for "LINQ to SQL" and Entity Framework for options based on ADO.NET
rei ayumi wrote: 4:How to make the buttons to scroll the info?
Depends, but normally you don't, the scroll appears when the data is too large to fit. Again, I'm not sure I understand your question.
rei ayumi wrote: 5:How to make the data to be read according to the link topic under the same
database?
It is impossible to tell you exactly how to do this, it depends how you are getting your data. With pure ADO.NET you query the database using the link topic to filter via an SQL WHERE clause. With LINQ and Entity Framework you can write a LINQ query to do the same job. The details depend exactly on which technology you use, what and how you want to filter.
Hope this helps.
[Edit]
Though the help is late, I didn't realise that I was not on "Page 1" of the forum and was answering a 5 year old question. If you do invent time-travel, go back and inform yourself that ADO.NET is your only option until 2007 IIRC.
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Hi,
I'm designing a form without a title form. To move the form around, I have to write another simple mouse_move event that will get the location of the mouse pointer and will replace the location of the form. It works, but the thing is, when i tried to move the form around, it flickers. I tried to use the doublebuffering style, but it still flickers. Anyone know why this is or how to handle this kind of situation? Also, the mouse pointer is off by a noticable distance from the form.
Anyone, please help. I am a newbie here, so please show me your guidance.
Thank you
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We can better help you if you post your MouseMove event code.
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woops sorry
Here's my code
dim MDown as boolean = False
Private Sub FormaName_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseMove
If MDown Then
Me.Location = Control.MousePosition
End If
End Sub
Private Sub FormName_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseUp
If e.Button = MouseButtons.Left Then
MDown = False
End If
End Sub
Private Sub FormName_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseDown
If e.Button = MouseButtons.Left Then
MDown = True
End If
End Sub
With This code, I have problems with the flickering and the pointer of and also with the pointer. Try it and you'll know what i mean, I'm not good at explaining :P
Thank you
-- modified at 11:54 Wednesday 16th November, 2005
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Private m_isMouseDown As Boolean = False<br />
Private m_lastMousePosition As System.Drawing.Point<br />
<br />
Private Sub FormName_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseDown<br />
If (e.Button = MouseButtons.Left) Then<br />
m_isMouseDown = True<br />
m_lastMousePosition = Me.MousePosition<br />
End If<br />
End Sub<br />
<br />
Private Sub FormName_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseUp<br />
If (e.Button = MouseButtons.Left) Then<br />
m_isMouseDown = False<br />
End If<br />
End Sub<br />
<br />
Private Sub FormName_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles MyBase.MouseMove<br />
Dim formPosition As System.Drawing.Point<br />
<br />
If (m_isMouseDown) Then<br />
formPosition = Me.Location<br />
formPosition.Offset(Me.MousePosition.X - m_lastMousePosition.X, _<br />
Me.MousePosition.Y - m_lastMousePosition.Y)<br />
m_lastMousePosition = Me.MousePosition<br />
Me.Location = formPosition<br />
End If<br />
End Sub
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It's Workingg  Thanks a lot 
For the flickering problem, i think it appears because i was using it as an mdiChild of another form. Also, I have so many controls on the form. Coz when i tried that code with a single form, it works just fine. Any idea how to handle this problem?
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Hmmm... I still can't reproduce this flicker issue, even in an MDI app. Perhaps my PC and video card is too good?
Does it flicker when your child forms have borders too?
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OO, I know why. Try create an image for your background and use it as backgroundimage For your MDIContainer, you'll get the flickering effect
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Okay. Now I'm seeing something.
I can seeing a painting issue while I'm dragging the child window.
Try this. Put the following code at the bottom of your MDI child form's constructor (the Sub New method).
Me.SetStyle(ControlStyles.DoubleBuffer, True)<br />
Me.SetStyle(ControlStyles.AllPaintingInWmPaint, True)
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Hi,
I already have that in there but it's still doing it. Is it because the background image keeps painting everytime we drag the child window? Is that what is happening? If it is, is there a way to stop the background image to stop refreshing?
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(Sorry about the late response. I was having Internet connection issues.)
As you drag the child window, the main window's background is going to need to redraw it's background. Otherwise you're going be leaving images of your child window behind as you drag it.
Applying double buffering seemed to improve the draw time significantly for me.
You may also want to try using a smaller background image. Smaller in dimension and color depth that is. This will improve the draw time. The image will tile automatically too if that'll work for you.
Also, a faster CPU and video card should improve the draw time as well.
If it still doesn't render fast enough, then you might have to consider dropping the background image.
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It's ok.
I tried your suggestion, but it still flickers. I tried to run it without the background image. It works fine, but when i have 2 forms, and if they intersect each other, it will flicker again. I know this was becoz of the redrawing thing that each control does everytime it's modified, but I can't figure out how to make them stoppp ARgGhh. There has to be some way to handle this problem, coz when i see the MS Excel or MS Access, they have a similar layout as mine, but they don't flicker -_-
Any other ideas?
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Regarding the flicker problem...
Can you tell me what kind of controls are on your child forms?
Are you catching the form's Move event?
Do you know if any of your controls are catching the form's Move event? (Wouldn't make sense, but doesn't hurt to ask.)
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I have a lot of Panel :P Does that matter?
I am trying to change the control. I'm designing a new form that looks similar without so many panels. Is it going to help?
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I doubt the Panels are the cause of the flicker.
I can't seem to reproduce this flicker issue and am therefore at a loss at what's causing it.
However, after doing an Internet search, I did find some references to MDI child window flicker issues like the one you are having. It sounds like the MDI container unnecessarily forces a WM_PAINT message on its children. Perhaps this search result can help you better than I.
http://www.google.com/search?hl=en&q=vb.net+mdi+flicker[^]
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In Win 2000 Pro , i want permit one user have right "read only " all file in one folder , i can not do it , can you tell me .
And when i make a new group ,why Window do not permit me add any right for that group ?
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I am attempting to edit an image to give it a non 3D effect. My problem is that the code does exactly what it is suppose to do  . Because of this, quite a few images have these big ugly streaks which completely mess up the affect, all because this green in a range of 5 was to close to this color of black. (Example: try this on C:\Documents and Settings\All Users\Documents\My Pictures\Sample Pictures\Water lilies.jpg). Does anyone have any alternative ideas of how to get a smooth image from this?
'Create a cartoonish like affect <br />
Public Function Cartoon(ByVal EditImage As Image, ByVal Range As Integer) As Image<br />
Dim ModBMP As New Bitmap(EditImage) 'Image to eidt<br />
Dim X As Integer, Y As Integer 'Positioning coordinates<br />
Dim ColorCapture As RGB 'Public Structure(3 integers to handle colors, nothing special)<br />
Dim Match As Boolean<br />
Dim R As Integer, G As Integer, B As Integer<br />
'Filter through<br />
For X = 1 To ModBMP.Width - 1<br />
For Y = 1 To ModBMP.Height - 1<br />
'Get color value of first position<br />
R = ModBMP.GetPixel(X, Y).R : G = ModBMP.GetPixel(X, Y).G : B = ModBMP.GetPixel(X, Y).B<br />
'Get color value of one pixel behind<br />
Try<br />
ColorCapture.R = ModBMP.GetPixel(X - 1, Y).R : ColorCapture.G = ModBMP.GetPixel(X - 1, Y).G : ColorCapture.B = ModBMP.GetPixel(X - 1, Y).B<br />
Catch ex As Exception<br />
'MsgBox(ex.Message)<br />
End Try<br />
'Modify to enhance check (crap code)<br />
'Dim Vivi As Integer = 0<br />
'Vivi = HighestColor(R, G, B)<br />
'If Vivi = 1 Then R = R * 5<br />
'If Vivi = 2 Then G = G * 5<br />
'If Vivi = 3 Then B = B * 5<br />
'Check Relations between two areas (ReAdjusted to hard way of adding booleans)<br />
Match = InRange(R, Range, ColorCapture.R) + InRange(G, Range, ColorCapture.G) + InRange(B, Range, ColorCapture.B)<br />
If Match = True Then R = ColorCapture.R : G = ColorCapture.G : B = ColorCapture.B<br />
'Adjust the image<br />
ModBMP.SetPixel(X, Y, Color.FromArgb(R, G, B))<br />
Next Y<br />
Next X<br />
EditImage = ModBMP<br />
Return EditImage<br />
End Function<br />
<br />
'Purpose: Check highest color value to help figure between small differences<br />
Public Function HighestColor(ByVal R As Integer, ByVal G As Integer, ByVal B As Integer) As Integer<br />
'Check<br />
Dim eR As Boolean, eG As Boolean, eB As Boolean<br />
'Evaluate<br />
If R < B And R < G Then eR = False<br />
If G < R And G < B Then eG = False<br />
If B < R And B < G Then eB = False<br />
If eR = True Then Return 1<br />
If eG = True Then Return 2<br />
If eB = True Then Return 3<br />
End Function<br />
<br />
'Purpose: Return boolean of whether in range of this number<br />
Public Function InRange(ByVal Number As Double, ByVal Range As Double, ByVal Target As Double) As Boolean<br />
'Check<br />
If Target <= Number + Range And Target >= Number - Range Then<br />
InRange = True<br />
Else<br />
InRange = False<br />
End If<br />
'Return Results<br />
Return InRange<br />
End Function
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You should read my image editing articles in C#. GetPixel/SetPixel is too slow. Can you do unsafe code in VB.NET ?
Is this a smoothing filter ? There's a smoothing filter in my C# articles/library.
Also, when you change a bitmap, you should call Dispose on the old one before getting rid of it.
Christian Graus - Microsoft MVP - C++
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I have been looking over your articles on image editing in c#. They offer many ideas and will be helpful for some over things I plan down the road. I am not sure of how to do unsafe coding in vb.net, but I will do some research on that.
No, this is not meant to be a smoothing filter in its idea... Lets say we have a picture of a flower, purple, light shining on one side, and there is a nice clear blue sky behind it. If it was a real picture, most of the pixels would be different, like the sky might have two blue pixels right next to each other of different values that are very close. My plan is to make it so they match, but not for a smooth affect. If all the sky becomes one shade of blue, each and every piece, and the flower becomes 2 different colors, it loses it real affect. It then becomes like an odd cartoon image, which is the affect I am aiming for.
I'll modify my code for the disposal. Thank you for your advice.
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