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wrote: i need correct implementation of multiple description coding technique in c#.
I did a quick google on that expression and all I found was a number of academic papers published within the last 5 years. You might get a positive response here, but you may have a better chance of receiving an answer by posting this question on an appropriate academic forum.
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Hello all!
Iam writing a tool that will develope elearning content for the web. This tool has to be run as a clientside application. After working on web applications for so long iam really unsure about what is the best language / development tools to develope such an application in.
Ive looked into developing it in c# as this is a language iam comfortable with but iam sure unsure on the whole about developing clientside applications with .net technologies and would like to know peoples considerations on doing this.
One consideration ive come accross is redistributing the .net framework for people who do not have it already installed. Ive read this can be as little as 22mb. Another thing iam concerned about is performance. I would like the application to run as fast as any other desktop tool, but obviously there is the concern that .net languages compile to CLR so there is a processing overhead there.
Another thing is that this application will have some pretty intense GUI requirements and iam unsure if c# is the right language for doing this kind of work.
Does anyone have any council to offer on this.....please?
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Mr Withers wrote: One consideration ive come accross is redistributing the .net framework for people who do not have it already installed. Ive read this can be as little as 22mb.
Is that really a concern. If you are distributing by CD then that is only about 4% of the disc. If you are distributing over the web 22Mb is not a lot these days.
Mr Withers wrote: Another thing iam concerned about is performance. I would like the application to run as fast as any other desktop tool, but obviously there is the concern that .net languages compile to CLR so there is a processing overhead there.
A one time overhead to compile to the most efficient code for the processor on the machine. You can distribute your app to 5 different machines and the JIT compiler will compile each differently to take advantage of the various hardware. You couldn't do that with a non-JITed language.
Mr Withers wrote: Another thing is that this application will have some pretty intense GUI requirements and iam unsure if c# is the right language for doing this kind of work.
Have you looked at WPF (Windows Presentation Foundation) in .NET 3.0?
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I do agree that 22mb isnt alot - i guess i was kinda putting in as more of a example consideration lol, I had no idea that the overhead was a onetime only - I was thinking back to java and JVM where it run horribly slow at times. This does sound very promising.
I assumed avalon (WPF) was longhorn/vista only, one of my requirements is that it runs on XP as well (I should have mentioned this). Looking past the visual studio toolbox ill probably have to look at GDI or whatever its become now unless iam mistaken?
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Mr Withers wrote: I assumed avalon (WPF) was longhorn/vista only, one of my requirements is that it runs on XP as well
WPF will run on XP
Mr Withers wrote: Looking past the visual studio toolbox ill probably have to look at GDI or whatever its become now unless iam mistaken?
From what I understand GDI has effectively been deprecated with the release of Vista. So long as you don't need to support Windows 2000 or earlier then I would say WPF is the way to go now.
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Thanks this sounds like the ways forwards, ill start doing some research into these things and get to grips with them.
A bit off topic - but I have to write a video hook that ties in with this app so I can grab video sequences of the user interacting with the desktop / applications.
Just wondering if this kind of thing is possible with c# or will it be a bit of a hack?
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hi i am using windows application...
i want to create crystal report using stored procedure pls help me..
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Hi
i have created a Find/Replace window for my editor.
when the user clicks on the Search button on menu,
i want only one instance of this window to be created.
and if it is already opened, it should be activated..
plz help how to do it..
regards,
nas
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make findandsearch window topmost
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Hi Kalyan,
Thanks for your Reply.
I have got it
I have made the form declaration globally.
With Thanks
Nas
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Hi all, I started playing around with ADO.NET, so what I did was create a database with a table called products, then I created the form, set the dataset to grid binding and then drag that table from the data source tab onto the form. It then created the gridview, added the binding navigation bar and everything, so I can view all the data, add new fields and save them.
So if I add new values in the grid and save them via the binding navigation bar it is saved to the data set and I can view every thing further in the program, but once I close the entire program and then open it again the values were never saved to the database? What am I missing or not doing?
Thanks in advance.
He who laughs last is a bit on the slow side
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hi
dude what happens when u use a dataset it is on the on memory..
it has to effect the database dataset wont effect the database until u do it
u need to take the help of dataadapter and update the database
byebye
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I am using a data adapter, but it looks as if it only updates the dataset and not the database. So I can create entries, update entries and it all is fine, if you go else where in the program and check the values they are 100%. But they aren't in the database it self, the changes never took effect on the database. So the next time I start the program, none of the changes where saved
He who laughs last is a bit on the slow side
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kaylan is correct... you need to call the dataAdapters.Update() function. Only then will the changes be made to the database.
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I do.
Here's the code to the update
private void productsBindingNavigatorSaveItem_Click(object sender, EventArgs e)
{
try
{
this.Validate();
this.productsBindingSource.EndEdit();
this.productsTableAdapter.Update(this.productsDataSet.Products);
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString(), "Error");
}
He who laughs last is a bit on the slow side
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It's over a year ago that i worked with ADO.NET and C# but i try to help you
You have seriously a DataAdapter to this DB-Table.
With DataAdapter.Update() you save all the changings to the Database.
( if all Commands are correct --> To fill in (DataAdapter.Fill() to fill a Dataset) the data is easy,
the DataAdapter needs only the SELECT-Command, but to update the Table it needs
all 3 other Commands ( INSERT,UPDATE and DELETE )
Perhaps it's a problem of the Commands.
But using the Binding Navigator seems me that it works directly on the DB and not on a Dataset
( i never used this technology (only Dataset) )
But the Commands are very important.
I hope i could help you a little bit
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Thanks for the quick reply, I checked the the commands and they are all there (Insert, Update and Delete)and working (checked them just to be sure). I use the update command of the DataAdpater to save the values, and all seems well through out the rest of the program, but the actual changes where never made to the database, as far as I understand it is the dataadapter that handles the update of the database, but it looks rather that it only updates the dataset and not the database
He who laughs last is a bit on the slow side
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No, the DataAdapter is an Interface between the Dataset and the Database.
The DataSet is like a collection of your DataTables, which are Tabes in your virtual Database (Dataset)
You can work during 1year on the Dataset and after 1year you commit (update) all to the database.
The Dataset is designed to speed up the work with a DB.
Because your DB could be in another country, with a 56K Connection.
You tried already to step into the functions ( with help of Breakpoints and F10-Key ) ?
Or call the Update() into a try-catch ? It's possible that an exception is fired.
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Yes, I have it in a try catch and step it through, no errors, it updates the grid with the changes and all the new fields added, but not the database.
Here's the code to the update
private void productsBindingNavigatorSaveItem_Click(object sender, EventArgs e)
{
try
{
this.Validate();
this.productsBindingSource.EndEdit();
this.productsTableAdapter.Update(this.productsDataSet.Products);
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString(), "Error");
}
He who laughs last is a bit on the slow side
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Sorry, but i cant imagine what is the error.
You can create a very simple project, fill all data to the DataTable, change one record and
make the Update to the DB ...
On a very small project you don't have a huge number of possibilities where the error can be hidden
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That's the problem, I don't receive an error, it does through as if everything was 100, but thanks for all your help, really appreciated.
He who laughs last is a bit on the slow side
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After the Update you need to update the dataSet to reflect changes. To do this add the following after you update the dataAdapter:
dataSet.AcceptChanges();
Hope this helps.
Mike
Started out with nothing and still have most of it left!
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Added that line
private void productsBindingNavigatorSaveItem_Click(object sender, EventArgs e)
{
try
{
this.Validate();
this.productsBindingSource.EndEdit();
this.productsTableAdapter.Update(this.productsDataSet.Products);
this.productsDataSet.AcceptChanges();
}
catch (Exception ex)
{
MessageBox.Show(ex.ToString(), "Error");
}
}
But still no effect on the database, the dataset gets updated but not the database
He who laughs last is a bit on the slow side
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Hmmm
The only other thing I can think of is that the EndEdit is used in wrong context...see code snippet below.
//If current item is not new and not cloned
if (!obj.IsNew && !obj.IsCloned)
{
drv = dvItem[index];
drv.BeginEdit();
}
else
drv = dvItem.AddNew();
//Transfer Shape data to DataView
obj.ObjectToDRV(drv, id);
drv.EndEdit();
daShape.Update(dsShapeEd1);
dsShapeEd1.AcceptChanges();
You'll notice that I only use the EndEdit if the object is being updated and not new!
Hope this helps.
Mike
Started out with nothing and still have most of it left!
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It is as if the data adapter doesn't commit the changes to the database and then performs a roll back, but I can't figure out how to commit it to the database
He who laughs last is a bit on the slow side
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