|
sounds like you should be using ShowDialog instead of Show. ShowDialog will automatically 'block' the main form, so you don't need to worry about disabling it
"An eye for an eye only ends up making the whole world blind"
|
|
|
|
|
Hello,
Can i use the showdialog() with more that 2 forms.
So i have the mainform , i opens a second form with frmxxx.showdialog and on that second form there are again a few buttons wich i use to open a 3th form , can i use the same showdialog there ?
thanks
DCA
|
|
|
|
|
No, you can only use it with one form from the mainform, but YES you can keep calling ShowDialog from the Parent to Childs.
what you can also do is set the AlwaysOnTop property to true on the 'popup' form which will change the ZOrder of the forms, keeping it in front.
|
|
|
|
|
When i have 3 forms mainform , form1 and form2
From the mainform i need to open form1 wich need to be set active (on this time the main form may not be accessable).
From the form1 that is on top of the (blocked)mainform i need to open from2 wich comes on top of form1 , so form1 must also be disabled like frmmain. and form2 must be active only.
When clicking on the OK button on Form2 the form2 needs to be disapear and frm1 needs to come active again , frmmain is still deactivated until ok isclicked on frm1.
My problem was when using form.enabled that is was to slow and the user was clicking to fast so the wrong forms came on top of eachother and where locked .
can you help me with this please.
thanks.
DCA
|
|
|
|
|
You can use the ShowDialog() in this instance.
i.e. on the mainform call form1.showdialog, and on form1 call form2.showdialog
|
|
|
|
|
Thanks
That is the correct solution.
best regards
DCA
|
|
|
|
|
Hello, this is Vikash Gohil.
I have a windows Service that runs a thread on starting and the thread uses a while loop.
Now I want to Use Sleep function in my windows Service.
I want to know is it really OK or is there any kind of risk involved in making a windows service sleep.
the sleep time i want to use is around 55 to 58 seconds.
Please could anyone give me some guidelines on this topic.
Awaiting a reply soon.
Thanks in Advance.
|
|
|
|
|
|
Thanks daveauld for the reply.
The post was really helpful.
Thanks Again
|
|
|
|
|
Hello everyone,
I'm in dire need of figuring out the best data structure that would satisfy my needs and yet utilize the power of Parallel programing introduced in VS 2010.
What this data structure should be able to do efficiently is the following:
-be able to contain elements defined as a specific Structure
-handle tons of repetitive iterations and searches over its elements
-handle not so complex math operations
-be able to easily change in size when necessary without putting extra load on the CPU and RAM
-handle being parallelized
Hopefully, I've made myself clear enough.
Any thoughts would be greatly appreciated ...
Agarwaen
|
|
|
|
|
you can apply parallelism easily if your data needs are limited to:
- reading global data (i.e. across all threads) that no thread will be writing to;
- only writing data that is local to the thread.
So you could easily do a global dictionary, created beforehand, and read by all threads; each thread creating its own collection of results; and when they all finish, maybe join all those results.
If your app doesn't satisfy those restrictions, you need thread synchronization, such as locks, in order to avoid one thread reading data at the very moment it is getting modified by another thread (and for most data structures, a modification may temporarily cause an inconsistent, even an invalid, state).
From your (pretty abstract) data requirements I think you want to read data that is changing often, so you need the synchronization. I might have misunderstood though, you'll have to decide for yourself.
The Parallel goodies .NET 4.0 introduced don't provide data access synchronization for you; all they do is launch a number of threads, and wait for them to join. That is thread synchronization, not data synchronization.
Luc Pattyn [Forum Guidelines] [Why QA sucks] [My Articles]
I only read formatted code with indentation, so please use PRE tags for code snippets.
I'm not participating in frackin' Q&A, so if you want my opinion, ask away in a real forum (or on my profile page).
|
|
|
|
|
Hi All,
I have one Excel sheet "Student.xls", which has different worksheet as "Sheet1","Sheet2"..like that.
Consider now "Sheet1"; it has 3 columns - "Name", "Age", "Sex". All these columns has row entries.
Now I have one access database, "alldata.mdb". It has One table "Record" which has 3 fields as same as column name of Excel sheet-- "Name", "Age", "Sex".
I want to populate this access database with the entries of Excel sheet from "Sheet1".
Can someone let me know how to do this?
I tried this:
// first connected xl datasheet:
Dim filename As String = "C:\Student.xls"
Dim con As String
con = "Provider=Microsoft.Jet.OLEDB.4.0;" & "Data Source=" & filename & ";" & "Extended Properties=Excel 8.0;"
Dim connection As OleDbConnection = New OleDbConnection(con)
connection.Open()
The above Excel connection was succesful, but how to import the data from this excel sheet into the access database.
Please suggest.
Thanks,
R.S.
|
|
|
|
|
|
Good Article
------------------------------------
I will never again mention that I was the poster of the One Millionth Lounge Post, nor that it was complete drivel. Dalek Dave
|
|
|
|
|
I have gone through this, and I tried to implement somehow. The implementation is as follows:
// first connected xl datasheet:
Dim filename As String = "C:\Student.xls"
Dim con As String
con = "Provider=Microsoft.Jet.OLEDB.4.0;" & "Data Source=" & filename & ";" & "Extended Properties=Excel 8.0;"
Dim connection As OleDbConnection = New OleDbConnection(con)
connection.Open()
// now copying the excel column into access database table columns:
Dim cmd As New OleDbCommand
cmd.Connection = connection
Try
cmd.CommandText = "SELECT * INTO [MS Access;Database=C:\alldata.mdb].[Record] FROM [Sheet1$]"
cmd.ExecuteNonQuery()
connection.Close()
MsgBox("The Import is Compelte")
Catch ex As Exception
MsgBox("Import Failed, correct Column name in the sheet!")
End Try
While executing I am getting following error:
The Microsoft Jet database engine could not find the object 'Sheet1$'. Make sure the object exists and that you spell its name and the path name correctly.
I am using Microsoft office 2007 with Access 2007 database.
Please tell me how to solve this?
Regards,
R.S.
|
|
|
|
|
The first thing to do would be to try and populate a dataset to prove the data is first getting read from Excel.
If you succeed with that then start trying to populate the access table.
I think for experimenting with new code, you are trying to do too much in one step. Start small, bite sized chunks, or you could end up getting confused by it all.
|
|
|
|
|
I am trying this:
Dim ds1 As New DataSet
Dim da As OleDbDataAdapter = New OleDbDataAdapter("SELECT * FROM [Sheet1$]", connection)
da.Fill(ds1)
But getting same error:
The Microsoft Jet database engine could not find the object 'Sheet1$'. Make sure the object exists and that you spell its name and the path name correctly.
|
|
|
|
|
I created a Student.XLSX file with the 3 columns as you stated in your OP.
The code below successfully ran and imported the data to a dataset which was then bound to a DataGridView;
Dim conBuilder As New OleDbConnectionStringBuilder
conBuilder.Provider = "Microsoft.Jet.OLEDB.4.0"
conBuilder.DataSource = "C:\Users\Dave Auld\Desktop\Student.xlsx"
conBuilder.PersistSecurityInfo = False
conBuilder.Add("Extended Properties", "Excel 8.0;HDR=YES;")
Dim con As New OleDbConnection
con.ConnectionString = conBuilder.ConnectionString
Dim com As New OleDbCommand("Select * from [Sheet1$]")
com.Connection = con
Dim da As New OleDbDataAdapter(com)
Dim ds As New DataSet
Dim rowcount As Integer = da.Fill(ds)
DataGridView1.DataSource = ds
DataGridView1.DataMember = ds.Tables(0).TableName
|
|
|
|
|
Hi,
I have copied the data in a new dataset "ds1". Please tell me how to copy this "ds1" contents into Access Database. I am trying with following:
Dim da2 As New OleDbDataAdapter
Dim conn As OleDbConnection
Dim cmd As OleDbCommand = New OleDbCommand()
conn = New OleDbConnection("Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\alldata.mdb;")
cmd = New OleDbCommand("SELECT * FROM Denver", con)
da2 = New OleDbDataAdapter(cmd)
da1.Fill(ds1, "Denver")
But not able to populate the Access database.
Can You guide me how to do this??
Thanks,
R.S.
|
|
|
|
|
|
You have to account for the fact that no two scans of the exact same card will result in a pixel-by-pixel equality. Every pixel is going to be a slightly different color than the same pixel in the previous scan.
If all you're doing is OCR'ing the business cards, why even bother comparing two images of the cards and just compare the data that's coming off them?
If you have to compare the images, then you'll have to implement a filter (in C#, not VB.NET!) to process the image to equalize the colors. For example, if you look at the white part of a business card, you'll see a scattering of pixels of different colors, not an even white acrossed all of them. You have to implement a filter to remove all those color variations to generate the nice flat color acrossed all pixels.
Search the articles for "image processing for dummies" and you'll find some good examples by Christian Graus.
Ph, you can't do this in VB.NET. If you wanted any speed at all, it has to be done in C#, or some other managed language that supports pointers. VB.NET doesn't.
|
|
|
|
|
dear dave... all you wroted isnt corect! download the archive which i posted and try to compare two images...
|
|
|
|
|
Dave Kreskowiak wrote: You have to account for the fact that no two scans of the exact same card will result in a pixel-by-pixel equality. Every pixel is going to be a slightly different color than the same pixel in the previous scan.
i know that and understand what you mean so i made:
Private Function CheckPixel(ByVal source_color As Color, ByVal search_color As Color, ByVal tolerancy As Integer) As Boolean
Dim sense As Long
sense = 255 - tolerancy * 5
CheckPixel = (System.Math.Sqrt((Val(source_color.R.ToString) - Val(search_color.R.ToString)) * (Val(source_color.R.ToString) - Val(search_color.R.ToString)) + (Val(source_color.G.ToString) - Val(search_color.G.ToString)) * (Val(source_color.G.ToString) - Val(search_color.G.ToString)) + (Val(source_color.B.ToString) - Val(search_color.B.ToString)) * (Val(source_color.B.ToString) - Val(search_color.B.ToString))) > sense)
End Function
wich is working ok for pixelbypixel search! but i dont want pixelbypixel search or do want i dont know thats why i posted a link to rapidshare file and application with source wich contains my needs!
Dave Kreskowiak wrote: If all you're doing is OCR'ing the business cards, why even bother comparing two images of the cards and just compare the data that's coming off them?
no i am not doing ocr. i have button "start" and then i scan image and compare to an image that is stored to database and detect difference on those two images and pixelbypixel is slow and not good result but with the code for detect difference from link i posted would do what i want! Here are images you can try with the application i posted and see what i want!
ORIGINAL : http://img96.imageshack.us/img96/3540/originalsp.jpg[^]
SCANED : http://img717.imageshack.us/img717/3461/damaged.jpg[^]
COMPARED : http://img32.imageshack.us/img32/5895/comparator.jpg[^]
Dave Kreskowiak wrote: If you have to compare the images, then you'll have to implement a filter (in C#, not VB.NET!) to process the image to equalize the colors. For example, if you look at the white part of a business card, you'll see a scattering of pixels of different colors, not an even white acrossed all of them. You have to implement a filter to remove all those color variations to generate the nice flat color acrossed all pixels.
yes i want compare... look at compared picture!
Dave Kreskowiak wrote: Search the articles for "image processing for dummies" and you'll find some good examples by Christian Graus.
thanks i will! 
|
|
|
|
|
Pf course your search is slow! First, you're using GetPixel, which takes an eternity to execute. Second, this code is garbage:
CheckPixel = (System.Math.Sqrt((Val(source_color.R.ToString) - Val(search_color.R.ToString)) * (Val(source_color.R.ToString) - Val(search_color.R.ToString)) + (Val(source_color.G.ToString) - Val(search_color.G.ToString)) * (Val(source_color.G.ToString) - Val(search_color.G.ToString)) + (Val(source_color.B.ToString) - Val(search_color.B.ToString)) * (Val(source_color.B.ToString) - Val(search_color.B.ToString))) > sense)
Your converting each RGB value component, say R, to a string, then back to a value. This is VERY time consuming an completely unnecessary. Not only are you doing it at all, you're doing it several times for each time you use the same value!
The only way you're going to improve performance is to scrap this code and rewrite it in C# and directly access the image data. You cannot do this in VB.NET because it requires the use of unsafe pointers, which VB.NET does not support.
Search the articles for "image processing for dummies" and you'll find a very good series of articles by Christian Graus explaining just how this is done.
|
|
|
|
|
General 
News 
Suggestion 
Question 
Bug 
Answer 
Joke 
Praise 
Rant 
Admin 
Submit an article or tip
