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Hi All,
I am a beginner for .Net technologies. I have few problems in adding dynamic row in grid view.
Please take a look at my code snippet. I have GridView which is populated by a table from database.
I want to give "ADD NEW INFO" option to the user. Following code really works sometime or It just duplicate the available rows and lists in the view.
and my OnUpdateClick is never triggered When it worked. Please help me. I welcome all suggestions
Thanks in Advance.
protected void btnBook_Click(object sender, EventArgs e)
{
GridViewRow newRow = new GridViewRow(-1,-1, DataControlRowType.DataRow, DataControlRowState.Normal);
newRow.Cells.AddRange(CreateCell());
Table tbl = GridView1.FooterRow.Parent as Table;
tbl.Rows.AddAt(GridView1.Rows.Count+1, newRow);
//TableCell cell = new TableCell();
//cell.Controls.Add(new LiteralControl("Footer Row"));
//newRow.Cells.Add(cell);
newRow.ID = "Dynamically Generated Row";
}
private TableCell[] CreateCell()
{
DataSet ds = (DataSet)Session["libDS"];
DataTable dsTable= ds.Tables["libBooks"];
int nRow = dsTable.Rows.Count + 100;
string row = nRow.ToString();
TableCell[] cells = new TableCell[5];
TableCell cell = new TableCell();
TextBox txt1 = new TextBox();
txt1.Text = row;
txt1.ReadOnly = true;
cell.Controls.Add(txt1);
cells[0] = cell;
cell = new TableCell();
txt1 = new TextBox();
txt1.Text ="";
cell.Controls.Add(txt1);
cells[1] = cell;
cell = new TableCell();
txt1 = new TextBox();
txt1.Text ="";
cell.Controls.Add(txt1);
cells[2] = cell;
cell = new TableCell();
txt1 = new TextBox();
txt1.Text ="";
cell.Controls.Add(txt1);
cells[3] = cell;
cell = new TableCell();
LinkButton link1 = new LinkButton();
link1.Text = "Update";
link1.Click += new EventHandler(OnUpdateClicked) ;
cell.Controls.Add(link1);
link1 = new LinkButton();
link1.Text = "Cancel";
link1.Click += new EventHandler(OnCancelClicked);
cell.Controls.Add(link1);
//link1 = new LinkButton();
//link1.Text = "Cancel";
//link1.OnClientClick ="OnUpdateClicked(false)";
cells[4] = cell;
return cells;
}
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Hey all,
I was wondering if there was a way for the WebBrowser Control to detect when a link is opening a new window, i.e. using:
Open a new window!
Any help would be appreciated!
Thanks!
Sean
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If i select Datemotnyear from datetimepicker i need display the day as mondayor Tuesday
How To display?
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myDateTimePicker.Value.DayOfWeek.ToString()
or
myDateTimePicker.Value.ToString("ddd")
or
myDateTimePicker.Value.ToString("ddddddddddd")
Luc Pattyn [Forum Guidelines] [My Articles]
this weeks tips:
- make Visual display line numbers: Tools/Options/TextEditor/...
- show exceptions with ToString() to see all information
- before you ask a question here, search CodeProject, then Google
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How can i build a messenger in .net? with id and password stored in server
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Decide how to store the ID and password. Write the code to access the IDs and passwords.
Decide the transport method and protocol for the messenging. Write the code to use that transport methd and protocol.
If you want more details there are plenty of tutorials you can search for on google.
If you have any specific problems, rather than generals ones then just ask and we'll be happy to help.
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Hi Guys
Is there a place in visual studio to select which version of the framework you'd like to use for a specific project?
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Studio 2003 targets 1.1 only
Studio 2005 targets 2.0 only (and 3.x which are just extensions)
AFAIK Orcas lets you choose exactly which >=2.0 you will target
Luc Pattyn [Forum Guidelines] [My Articles]
this weeks tips:
- make Visual display line numbers: Tools/Options/TextEditor/...
- show exceptions with ToString() to see all information
- before you ask a question here, search CodeProject, then Google
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Luc Pattyn wrote: AFAIK Orcas lets you choose exactly which >=2.0 you will target
Yes, that is the case. The default for new projects is .NET Framework 3.5, but you can change it as needed to 3.0 or 2.0.
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Not until Visual Studio 2008 is released, unless you want to use the Beta 2 release.
Visual Studio Version .NET Framework Version
--------------------------------------------------------------------
Visual Studio.NET 1.0
Visual Studio 2003 1.1
Visual Studio 2005 2.0
Visual Studio 2005 with .NET 3.0 Extensions 3.0
Visual Studio 2008 3.5, 3.0, 2.0
-----------------------------
In just two days, tomorrow will be yesterday.
http://geekswithblogs.net/sdorman
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Thanks for the info guys. I found what I was looking for under
Project -> Properties -> Build -> Change Button
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Visual Studio 2005 has a Version Selector component right?
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I was running one of my assemblies through FxCop and got this message:
"As it is declared in your code, parameter 'handle' of PInvoke NativeMethods.waveOutGetVolume(Int32, Int32&):Int32 will be 4 bytes wide on 64-bit platforms. This is not correct, as the actual native declaration of this API indicates it should be 8 bytes wide on 64-bit platforms. Consult the MSDN Platform SDK documentation for help determining what data type should be used instead of 'System.Int32'."
I've been looking at MSDN and haven't found anything yet specific to this problem. Still looking. But I thought I'd go ahead and ask here. How do you declare your interop methods so that they work correctly on both 32-bit and 64-bit systems?
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Use IntPtr in place of Int32.
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Abisodun wrote: Use IntPtr in place of Int32.
But does this mean having to allocate unmanaged memory for the pointer?
If I do this:
IntPtr handle = new IntPtr();
int result = waveOutOpen(handle, deviceID, ref format, 0, 0, CALLBACK_NULL);
waveOutOpen returns an error.
If I have to allocate unmanaged memory for the pointer (ugh), how do I tell how much to allocate? On a 32-bit system it will be 4 bytes. On a 64-bit system it will be 8 bytes.
[EDIT]
Nevermind. I discovered that I need to declare my interop method like this:
[DllImport("winmm.dll")]
public static extern int waveOutOpen(out IntPtr handle, int deviceID, ref WaveFormat format,
int dummy, int instance, int flags);
The key is to use the out modifier on the IntPtr parameter.
Thanks for your help.
[/EDIT]
-- modified at 13:34 Friday 17th August, 2007
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The size of IntPtr changes depending on the proc. So, an IntPtr on a 32-bit system is 32-bits wide and on a 64-bit system is 64-bits wide, automatically.
You don't have to allocate anything. You're just using the pointer as a self-sizing integer.
IntPtr handle = IntPtr.Zero;
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Dave Kreskowiak wrote: The size of IntPtr changes depending on the proc. So, an IntPtr on a 32-bit system is 32-bits wide and on a 64-bit system is 64-bits wide, automatically.
You don't have al allocate anything. You're just using the pointer as a self-sizing integer.
Understood. I think I was running into problems when I tried switching to IntPtr because I was using the ref modifier on the IntPtr parameter instead of out.
Thanks for your help.
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Hi Leslie,
here is my theory (still theory since I have not run any of this on Win64):
- for native pointers you really should use IntPtr, and it is not hard to do so.
- Win32 uses 4B pointers, Win64 needs 8B pointers
- you must build for either 32-bit or 64-bit
- on Win64 everything must be consistent (all modules 64-bit is fine, and
all modules 32-bit runs in some compatibility mode, not sure tho)
- IntPtr is a value type that holds either 4B or 8B pointer value
- IntPtr must be initialized, normally you give its value at construction
- a lot of P/Invoke examples are wrong, and use int/uint where it should have
been IntPtr. Most notably SendMessage: lParam, wParam and return value should
be regarded as IntPtr, and cast to int or whatever if and when appropriate.
- correct prototypes would have IntPtr for anything that is or could be a handle
(such as lParam).
Your problem seems to be you did not initialize handle.
Luc Pattyn [Forum Guidelines] [My Articles]
this weeks tips:
- make Visual display line numbers: Tools/Options/TextEditor/...
- show exceptions with ToString() to see all information
- before you ask a question here, search CodeProject, then Google
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Luc Pattyn wrote: here is my theory (still theory since I have not run any of this on Win64):
- for native pointers you really should use IntPtr, and it is not hard to do so.
- Win32 uses 4B pointers, Win64 needs 8B pointers
- you must build for either 32-bit or 64-bit
- on Win64 everything must be consistent (all modules 64-bit is fine, and
all modules 32-bit runs in some compatibility mode, not sure tho)
- IntPtr is a value type that holds either 4B or 8B pointer value
- IntPtr must be initialized, normally you give its value at construction
- a lot of P/Invoke examples are wrong, and use int/uint where it should have
been IntPtr. Most notably SendMessage: lParam, wParam and return value should
be regarded as IntPtr, and cast to int or whatever if and when appropriate.
- correct prototypes would have IntPtr for anything that is or could be a handle
(such as lParam).
Thanks for this explanation.
I've got a lot of code revision to do. I have older "toolkits" whose P/Invoke methods are apparently wrong, or will at least break on a 64-bit system.
Luc Pattyn wrote: Your problem seems to be you did not initialize handle.
Actually, I don't think I'm suppose to initialize the handle, rather I should use the out modifier on the IntPtr parameters rather than ref, as I had initially tried.
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Leslie Sanford wrote: Actually, I don't think I'm suppose to initialize the handle, rather I should use the out modifier on the IntPtr parameters rather than ref, as I had initially tried
That depends entirely on the function at hand; you typically need to provide
an IntPtr or be ready to receive one (with "out" keyword).
I don't recall any Win32 function that provides a handle that way, they typically
use the return value (and return zero for error, then you would call GetLastError
for details).
Greetings
Luc Pattyn [Forum Guidelines] [My Articles]
this weeks tips:
- make Visual display line numbers: Tools/Options/TextEditor/...
- show exceptions with ToString() to see all information
- before you ask a question here, search CodeProject, then Google
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Luc Pattyn wrote: That depends entirely on the function at hand; you typically need to provide
an IntPtr or be ready to receive one (with "out" keyword).
I don't recall any Win32 function that provides a handle that way, they typically
use the return value (and return zero for error, then you would call GetLastError
for details).
Oh, I wasn't clear. The example I gave in my earlier post was with waveOutOpen; it opens a waveform output device. The native version takes an pointer to a WAVEOUT handle and returns a MMRESULT value indicating the status of the operation. If the operation was successful, the handle is filled with a valid handle to the device. This handle is later used with other waveOutXXX functions to interact with the device.
So in this specific case, I needed an unitialized IntPtr to pass as the handle modified by the out keyword.
After the wave device has been opened, other waveOutXXX functions that are called expect the handle to be initialized.
Does this make sense?
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Leslie Sanford wrote: Does this make sense?
Of course, it does.
I was not familiar with waveOutOpen, but I looked it up now, and you are right,
it does output a handle, hence "out someIntPtr" is the right way to go.
The only comment I could make is you don't need the "=new IntPtr()" part of
your handle declaration, a simple "IntPtr handle;" should suffice.
Luc Pattyn [Forum Guidelines] [My Articles]
this weeks tips:
- make Visual display line numbers: Tools/Options/TextEditor/...
- show exceptions with ToString() to see all information
- before you ask a question here, search CodeProject, then Google
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Thanks for your responses.
I have to say that this has been a humbling day. Code that I had written a couple of years ago that I thought was fine has turned out not to be correct. I've had to go back through my code and correct this problem.
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First of all, you're welcome.
Second, that is a common situation when the playing field changes.
Things are working fine, they look good, compile without hassles, run great,
so you think they might be correct; and then something changes, it may still
work fine, but we got new information or new insights, and we feel we have
to adapt the code, so we learn new ways to be even "more correct" about it.
I have lots of experience in writing C code for different embedded systems,
and I can tell you, if you use five different compilers, it is just impossible
to write one page of code that all compilers will digest without giving a single
warning.
Things have improved, newer languages are more strict; having a single tool vendor
(Microsoft) also helps. But then documentation, whatever they try, is not good
enough. It is great at describing API functions, and less so for general
principles, do's and don'ts, etc.
And to make matters worse, you need more than is officially available (examples,
suggestions, bug work-arounds, ...) but lots of things you find on Internet
(including on CP) seem OK but are plain wrong, often the authors are satisfied
they got something that works, but did not bother (enough) about correctness and
general fitness.
I did investigate the IntPtr stuff when I developed TrayIconBuster (see one of my
CP articles); I was hoping it would run on XP, Vista and Win64 and had read some
messages signaling pitfalls in Win64. Having only XP-32 available, I had to research
a lot before I came up with "my theory", the one I presented earlier. And I must
admit, I did not get most of it from Microsoft documentation, and I don't really
have proof, having only XP to test on.
In earlier code I did not even use IntPtr, I used uint instead (the IntPtr stuff
did not seem to have any added value, just some coding overhead), but I too learned
it the hard way, so a couple weeks ago I revisited all my P/Invoke stuff and fixed
the pointers. Having my own classes (LP_user32, LP_kernel32, ...) holding the
prototypes helped a lot in finding them all; so it was a matter of adapting the
prototypes, then let the compiler discover the remaining problem spots.
One thing I did not understand from day one I started with .NET is why the heck
doesn't Microsoft do what www.pinvoke.net is trying to do, i.e. provide complete and
accurate prototypes for ALL Win32 functionality; they did provide all the header
files in older Visual C versions, and they must have the files internally.
Having them from MS would have improved their quality and completeness.
Unfortunately I have two more comments:
- there is a concept of safe handles since .NET 2.0; I have not studied it yet;
- I just discovered a "HandleRef" structure, which has existed since 1.0
(although its ToIntPtr method is new since 2.0)
Taken together, I would doubt turning handles simply into IntPtrs is really OK.
So I am afraid the theory is still evolving...
Is this a humbling experience ? I don't know; I do realize the more you learn,
the more you realize you don't know much. But that's fine by me, it won't stop
my eagerness to learn.
BTW I am a chess player, and it is my daily experience: some people know more
about the game, some less. You can try to work your way up, you may succeed in
improving your average, but the net result is some people know more, some less.
However hard you try. Well, unless you are at Kasparov's level that is. 
Cheers.
Luc Pattyn [Forum Guidelines] [My Articles]
this weeks tips:
- make Visual display line numbers: Tools/Options/TextEditor/...
- show exceptions with ToString() to see all information
- before you ask a question here, search CodeProject, then Google
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I am having a Select Query which is suppose to select multipple records from a table (MS-Access). I am using OLEDB from my connection and using OLEDB Adapter and datasets to desplay data. But I want to perform an operation on Each records after selecting from the DB- Which I want to Diaplay to the Data Grid also. But By using the OLEDB i am unable to collect the information from the records before binding. Is any way there to take the records and operate on it before binding, and using OLEDB ?
Dim con As OleDbConnection<br />
Dim cmd As OleDbCommand = New OleDbCommand<br />
Dim dataSet As dataSet = Nothing<br />
Sub BindGrid()<br />
Dim oleDbDataAdapter As OleDbDataAdapter = Nothing<br />
Dim ConnectionString = System.Configuration. _<br />
ConfigurationSettings.AppSettings(ConConstant.MS_ACCESS_CONNECTION_STRING)<br />
' Ge the sql query<br />
Dim SelectQueryText As String = String.Empty<br />
SelectQueryText = "Select Leave_Code as LeaveCode,Leave_Name as LeaveName,NoOfDays as Days from Leave_Mstr"<br />
oleDbDataAdapter = New OleDbDataAdapter(SelectQueryText, _<br />
New OleDbConnection(ConnectionString))<br />
' Create the data set<br />
dataSet = New DataSet<br />
' Fill the data set with the data<br />
oleDbDataAdapter.Fill(dataSet)<br />
If (Not oleDbDataAdapter Is Nothing) Then<br />
oleDbDataAdapter = Nothing<br />
End If<br />
With dgLeavCrtnLeavDtls<br />
.DataSource = dataSet<br />
.DataMember = dataSet.Tables(0).TableName<br />
.DataBind()<br />
End With<br />
End Sub<br />
Sub tablebind()<br />
Dim oleDbDataAdapter As OleDbDataAdapter = Nothing<br />
Dim ConnectionString = System.Configuration. _<br />
ConfigurationSettings.AppSettings(ConConstant.MS_ACCESS_CONNECTION_STRING)<br />
' Ge the sql query<br />
Dim SelectQueryText As String = String.Empty<br />
SelectQueryText = "Select Leave_Code as LeaveCode,Leave_Name as LeaveName,NoOfDays as Days from Leave_Mstr"<br />
oleDbDataAdapter = New OleDbDataAdapter(SelectQueryText, _<br />
New OleDbConnection(ConnectionString))<br />
' Create the data set<br />
dataSet = New DataSet<br />
' Fill the data set with the data<br />
oleDbDataAdapter.Fill(dataSet)<br />
Dim dh As TableHeaderCell<br />
Dim dc As DataColumn<br />
Dim dr As DataRow<br />
For Each dr In dataSet.Tables(0).Rows<br />
Dim trow As New TableRow<br />
For Each dc In dataSet.Tables(0).Columns<br />
Dim tcell As New TableCell<br />
tcell.Controls.Add(New LiteralControl(dr(dc.ColumnName).ToString))<br />
trow.Cells.Add(tcell)<br />
Next<br />
Next<br />
End Sub
This is the function I am using to desplay values to tables.Here i want to take the All the available leave codes to an array or some variable and want to process on it.
Praveen.K
System Engineer
Graviton Technologies Pvt.Ltd
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