Visual Basic

Johan Hakkesteegt7-Aug-07 22:51

Johan Hakkesteegt

7-Aug-07 22:51

Hi Terry,

Trupti Mehta wrote:
Private Sub UpdateDetails()
If (MsgBox("Are you sure to Update the Changes made? ", MsgBoxStyle.YesNo, "Update Details") = MsgBoxResult.Yes) Then
' Me.EmpDataSet.Tables("tblEmployee").AcceptChanges()
Dim i As Integer = Me.TblEmpTableAdapter.Update(Me.EmpDataSet.tblEmployee)
Me.EmpDataSet.AcceptChanges()
MsgBox("Updated Status = " + i.ToString())
End If
End Sub

The first thing that I notice in your code, is that you called .AcceptChanges and then .Update and then once again .AcceptChanges. This is not necessary and in this case would have even caused the problem.

Here is why: when a user makes changes in the datagrid, the rowstate of the rows in the linked DataSet will change accordingly. Change a value and the rowstate becomes something like "changed", delete a row and its rowstate becomes "deleted" (or that is the general idea anyway). When you call .Update the dataset will compare the rows with an altered rowstate, with the corresponding rows in the database, implement the changes where necessary, and finally reset the rowstates and refresh the dataset.

Now when you first call .AcceptChanges all these rowstates are reset. When you now call .Update there are no altered rowstates, and therefore the dataset has nothing to compare, nor implement.

Apparently you commented the first .AcceptChanges away, so as far as I can tell it should work. You may however want to also remove the second .AcceptChanges, as .Update already does that. One thing you could check is that there isn't some other function or sub that calls .AcceptChanges before the user tries to update his order (this is a mistake I made once, and it took me weeks to finally figure out that I called .AcceptChanges somewhere else entirely).

The .Update method will actually implement all changes for you, also deleting rows, etc. If you want to give a user the chance to change his mind about deleting a row, you can just call .AcceptChanges, .Clear and then DataAdapter.fill(YourDataSet) if he chooses 'No' or .Update if he chooses 'Yes'.

Hope this helps,

Johan

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

Trupti Mehta8-Aug-07 0:33

Trupti Mehta

8-Aug-07 0:33

Thanks Johan,

But nothing worked. AcceptChanges was before also as I was just trying to figure out working here & there. Otherwise the code is :

Dim i As Integer = Me.TblAlbumsTableAdapter.Update(Me.AlbumsDataSet.Tables("tblAlbums"))
MsgBox("Updated Status = " + i.ToString())

Dataset has 2 table in it. I tried the above way & also by passing Dataset. That goes to ListSelectionEvent Changed (1 table is connected to the list) and then to second where I want to make changes. It just gors to ReadOnly Property .. Me.TableBase . Nothing else. Do I need to manually set the values of current changed row to DS or some other way.

For Delete also :

If (MsgBox("Are you sure, you want to Delete the record ", MsgBoxStyle.YesNo, "Delete Record?") = MsgBoxResult.Yes) Then
    Me.TblAlbumsTableAdapter.Update(Me.AlbumsDataSet)
    MsgBox("Record Deleted")
Else
    Me.AlbumsDataSet.RejectChanges() ' .AcceptChanges()
    Me.AlbumsDataSet.Tables("tblAlbums").Clear()
    Me.PopulateDataGrid(Me.categoryList.SelectedIndex + 1)
    Me.AlbumsDataGrid.Refresh()
End If

If No is selected, the row gets deleted, on selecting other list item & returning to the same, it shows the record back. If Yes is selected, it happens the same way. But, it is NOT deleted from DB.

I hope you can help me out more with the problem.

Thanks

Terry

Johan Hakkesteegt8-Aug-07 22:49

Johan Hakkesteegt

8-Aug-07 22:49

Hi Terry,

From what I can tell, the problem with the db not being updated, happens because somehow the connections between your database, DataAdapter, DataSet and DataGrid are not configured correctly.

Perhaps you could try to add a new test form to your app, put a datagrid on it, then create a DataAdapter that gets data from a single (test) table only, create a DataSet from it, and then select the dataset as the datasource in the datagrid properties. Load the data into the datagrid during the load event () and update the table in the database with a button and the .Update method. See if it works, and if it does, you can check how this test differs from your case. If the test doesn't work, you may have to do some additional googling about why not.

As for your delete code, it is actually working the way it should according to your code. .RejectChanges only resets the rowstates in the dataset. I am not sure what this PopulateDataGrid does, but if it doesn't include a .Fill somewhere, then it is correct that your datagrid does not actually update its content. .Refresh will actually only repaint the control, and is best avoided, because it can screw up the scrollbars.

Good luck,

Johan

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

crystal reportviewr problem

Trupti Mehta9-Aug-07 1:02

Trupti Mehta

9-Aug-07 1:02

Thanks Johan,

.Accept or Reject nothing was working. Finally someone like you suggested me to use e of Eventargs
e.Cancel
That worked out. With that the event procedure is cancelled and you are back to normal. Nothing else is required.

Reg. Update, now finally things have come to track. Actually the code was proper & well. But, I didn't select Copy if newer of CoptToOutpurDir property of Database. That was Copy Always which was creating all the problem. That point someow clicked in my mind last night & things got working.

Thanks a lot for all the effort and interest.

I really appreciate your help and guidance.

Thanks

Terry

magedhv4-Aug-07 22:04

magedhv

4-Aug-07 22:04

<br />
        s = "drop view q1"<br />
        cmd.CommandText = s<br />
        dr = cmd.ExecuteReader()<br />
        dr.Close()<br />
<br />
<br />
<br />
<br />
<br />
        s = "create view q1 as select sum(fatrq1)reglz from reglz where fatrdate between '" + str + "'and'" + str2 + "'"<br />
        cmd.CommandText = s<br />
        dr = cmd.ExecuteReader<br />
        dr.Close()<br />
<br />
        Form7.Show()<br />

in form 7 i put this code
CrystalReportViewer1.ReportSource = ("CrystalReport1.rpt")
and i saved my report in debug
and when i when i click the bottom to show the report
he tell me error loading the report

is there any one to help me

Re: crystal reportviewr problem

Rupesh Kumar Swami6-Aug-07 0:57

Rupesh Kumar Swami

6-Aug-07 0:57

hi,
specify the error in detail.
anyway use this procedure (in place of Form7.show) to show report

call crystalForm.showReport()

where crystalForm contains crystalReportviewer and showReport procedure.

Private sub ShowReport()<br />
Try<br />
            Dim obj As CrystalReport1 = New CrystalReport1<br />
            Dim ds As New DataSet<br />
            Dim da As OleDbDataAdapter<br />
            Dim str As String<br />
            str = "select * from TableName"  'Query<br />
          <br />
            da = New OleDbDataAdapter(str, conn) ' where conn is connection object<br />
            da.Fill(ds)<br />
            <br />
            obj.SetDataSource(ds.Tables(0))<br />
            me.CrystalReportViewer1.ReportSource = obj<br />
            Me.Show()<br />
        Catch ex As Exception<br />
            MsgBox(ex.Message, MsgBoxStyle.Information, "Report")<br />
        End Try<br />
End sub

one more thing ,CrystalReport1.rpt must be include in your project (not in debug folder)

hope this helps

Rupesh Kumar Swami
Software Engineer,
Integrated Solution,
Bikaner (India)

Decimal Point

WestSideRailways4-Aug-07 19:22

WestSideRailways

4-Aug-07 19:22

Hi there,

The user input a decimal number 123.456, how do i work on the number behind the decimal point.

Re: Decimal Point

Luc Pattyn5-Aug-07 0:13

Luc Pattyn

5-Aug-07 0:13

Hi,

integer numbers can't handle the fractional part.
Floating-point numbers can; that is their purpsoe.
Look for the Single and Double data types, and the corresponding classes.
Double.TryParse() may suit your needs.

If this is new to you, I strongly recommend you buy an introductory book on
VB.NET and work your way through it.

Smile | :)

Luc Pattyn

try { [Search CP Articles] [Search CP Forums] [Forum Guidelines] [My Articles] }
catch { [Google] }

Re: Decimal Point

WestSideRailways5-Aug-07 9:44

WestSideRailways

5-Aug-07 9:44

Luc Pattyn wrote:
ForumVisual Basic / VB.NET
Subject:Re: Decimal Point
Sender:Luc Pattyn
Date:6:13 5 Aug '07

Hi,

integer numbers can't handle the fractional part.
Floating-point numbers can; that is their purpsoe.
Look for the Single and Double data types, and the corresponding classes.
Double.TryParse() may suit your needs.

If this is new to you, I strongly recommend you buy an introductory book on
VB.NET and work your way through it.

Luc Pattyn

Integer numbers can't handle fractions, WELL DUH....Anyone knows that Mad | :mad:

Everyone needs a little help, now and then, even people like you.........

Re: Decimal Point

Luc Pattyn5-Aug-07 10:07

Luc Pattyn

5-Aug-07 10:07

Yeah, I need help in guessing which elementary things you know and don't know.

The integer part of a floating-point number is available by ... to ...,
or by using the ... method, and the fractional part is what is left when you
subtract the integer part from it. But of course you knew all that.

Now what is the question ?

Smile | :)

Luc Pattyn [Forum Guidelines] [My Articles]

this weeks tips:
- make Visual display line numbers: Tools/Options/TextEditor/AllLanguages/General
- show exceptions with ToString() to see all information
- before you ask a question here, search CodeProject, then Google

Datagridview Comboboxs

ryan1174-Aug-07 11:19

ryan117

4-Aug-07 11:19

I'm creating a datagridview in VS2005, and two of the columns is comboboxes. I don't know how to change to populate the datasource to 2nd combox from the selection on the 1st combox. The point is I don't know how to return the value from the 1st combox selection on a row. Could someone here tell me how, please

Your Helps are Very Appreciated. Ryan

Which programing Language is best for me?

Benjamin Dodd4-Aug-07 9:40

4-Aug-07 9:40

Hello, i am 16, at the moment i am learing VB 6 however was recently told this isnt the best language to use. I am familier with the bascis of C++, should i contiue to learn C++?

Which language would you say would help me get started into the world of proggraming?

I know the basics of VB 6, HTML and C++, so i have some knoledge haha

Benjamin Dodd

Rareed4-Aug-07 10:18

Rareed

4-Aug-07 10:18

It really depends on what you want to do. For web programming, PHP, ruby, or asp.net would probably be good choices.

For desktop programming, C++ would definitely be the way to go, although java might also work well for you.

Also, at some point I'd really recommend spending some time with C and assembly. They aren't necessarily the best introductory languages (although the first programming class I ever took started from assembly and then went to C), but a good grasp of the low level workings of the computer will help you out.

Benjamin Dodd4-Aug-07 10:22

4-Aug-07 10:22

ooo thanks i have experince with C++, i will use C# i think as i have had it reconmended to me.

Rareed wrote:
For desktop programming

this i what i want to do desktop programming, i will use C# i think

Thanks

Benjamin Dodd

The ANZAC4-Aug-07 12:52

The ANZAC

4-Aug-07 12:52

c# is a good middle ground for you, although, c# and vb.net are virtually identical in power. There is a stigma that C# is better because it used to better the better of the two, now microsoft has basically built C# and VB.net from the same stuff and used different syntax. If you prefer the sentence like interaction of VB.net syntax, i'd go for that. But if you like the C# style then i'd go for that.

Please check out my articles:
The ANZAC's articles

Colin Angus Mackay4-Aug-07 12:58

Colin Angus Mackay

4-Aug-07 12:58

Rareed wrote:
For desktop programming, C++ would definitely be the way to go

I would tend to disagree. C# is an excellent language for developing desktop applications. I would suggest that more desktop applications are written in C# than C++ nowadays. Sure, the big old applications like Word and Excel are likely written in C++ or C, but modern business applications aren't.

Upcoming events:
* Glasgow: Mock Objects, SQL Server CLR Integration, Reporting Services, db4o, Dependency Injection with Spring ...

"I wouldn't say boo to a goose. I'm not a coward, I just realise that it would be largely pointless."

My website

Christian Graus4-Aug-07 13:28

Christian Graus

4-Aug-07 13:28

Agreed

Christian Graus - Microsoft MVP - C++

"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

Mohammed Hameed5-Aug-07 9:52

Mohammed Hameed

5-Aug-07 9:52

The easiest solution is that learn FORTRAN as quick as possible. Thats all I can say you at this time. Laugh | :laugh:

Be a good professional who shares programming secrets with others.

Colin Angus Mackay4-Aug-07 12:55

Colin Angus Mackay

4-Aug-07 12:55

Benjamin Dodd wrote:
at the moment i am learing VB 6 however was recently told this isnt the best language to use.

It is a dead language. It was superceded in 2002 by VB.NET

Benjamin Dodd wrote:
I am familier with the bascis of C++, should i contiue to learn C++?

It is a useful language to have.

What really matters is what you want to do with it. However, a good grounding in any modern language will provide you with a transferrable skill set.

Kevin McFarlane5-Aug-07 9:48

Kevin McFarlane

5-Aug-07 9:48

Colin Angus Mackay wrote:
a good grounding in any modern language will provide you with a transferrable skill set.

If only recruiters saw it that way. Cry | :((

Kevin

Christian Graus4-Aug-07 13:29

Christian Graus

4-Aug-07 13:29

VB6 is a waste of time. VB.NET is fine, but C# is also good. The bottom line is, there is no such thing as knowing too many languages. The only reason VB6 is a waste is that it's a dead language. I'd learn C#, because of the C++ background, and because going to VB.NET is easy, if you need to, when you know C#. But, keep using C++, there's no law against using more than one, it's not like marriage.

Christian Graus - Microsoft MVP - C++

"I am working on a project that will convert a FORTRAN code to corresponding C++ code.I am not aware of FORTRAN syntax" ( spotted in the C++/CLI forum )

Benjamin Dodd4-Aug-07 21:55

4-Aug-07 21:55

Christian Graus wrote:
there's no law against using more than one, it's not like marriage.

haha

Ok Thanks for the advice, i will begin to learn C# from today onwards Smile | :)

, i will also continue with C++.

Thanks for the advice

Benjamin Dodd

Versions of Visual Basics -

Mbire5-Aug-07 21:50

Mbire

5-Aug-07 21:50

I am assuming that you will be moving to the .Net platform sooner or latter. If thats the case then go for the language you feel good and strong about personally. Under the .Net platform, all languages have exactly equal capabilities (at least according to some Microsoft learning aids) and you can do the same task in almost the same number of lines and using the exact same classes and data types. Knowing more languages wont do you harm though, given that due to cross language programming now taking place, you might have to use and debug components written in another language.

However C# is more universally used: by Microsoft and major players.

Benjamin Dodd4-Aug-07 8:12