DataSet Problem ! - C# Discussion Boards

Re: RegEx

MarcelloTurnbull6-Jan-09 7:25

MarcelloTurnbull

6-Jan-09 7:25

Hi
Try www.regexlib.com

Regards

Marcello Turnbull

calling a matlab function from c#

yrajwan6-Jan-09 2:54

yrajwan

6-Jan-09 2:54

Hi,

I am currenlty working on a project that contains heavy data processing in matlab (the algorithm already exists in matlab as an m-file), however the GUI of the program must be written in c#.

My purpose is to invoke the m-file from c#, and to get the output back to the c# program.

I wanted to know how it can be done (is there a way to include the matlab code in c# as a DLL or something similar?)

Thank you for you help,
Yigal.

Re: calling a matlab function from c#

EliottA6-Jan-09 3:18

EliottA

6-Jan-09 3:18

What is this? Could it be a brief search resulting in 3.6 million results, with examples and documentation? It even looks like the first 3 links might be *exactly* what you are looking for.[^]

When researching such a broad topic, google will often find you better results faster with a much more extensive explanation with documentation then you will find on any forum.

Re: calling a matlab function from c#

yrajwan6-Jan-09 3:26

yrajwan

6-Jan-09 3:26

Thanks for your reply but this is not what i am looking for.

Believe me, i have been googling the whole morning and didn't find what i have been looking for.

Does anyone have a solution to my problem?

Thank you.

Re: calling a matlab function from c# [modified]

EliottA6-Jan-09 3:28

EliottA

6-Jan-09 3:28

yrajwan wrote:
Thanks for your reply but this is not what i am looking for.

In the OP you said that you wanted C# to be the interface...

quote from Mathworks[^] which is the first hit on that google query. This quote is actually the first line in the second paragraph.

The first method shows how to use the MATLAB as an automation server from C# using the engine interface via com automation.

Edit:
Posted wrong link Click here for a CP article on MATLAB and .NET[^]

modified on Tuesday, January 6, 2009 9:41 AM

OT- Welcome in the CP's memorable quotes

CPallini6-Jan-09 6:16

CPallini

6-Jan-09 6:16

Welcome in the CP's memorable quotes list [^].
Smile | :)

If the Lord God Almighty had consulted me before embarking upon the Creation, I would have recommended something simpler.
-- Alfonso the Wise, 13th Century King of Castile.

This is going on my arrogant assumptions. You may have a superb reason why I'm completely wrong.
-- Iain Clarke

[My articles]

Re: OT- Welcome in the CP's memorable quotes

EliottA6-Jan-09 6:23

EliottA

6-Jan-09 6:23

Yay!!

One more item of my list of things to do in 2009.

DataSet Problem !

Mohammad Dayyan6-Jan-09 2:39

Mohammad Dayyan

6-Jan-09 2:39

Hi guys.
I've added a database in my project. VS2008 SP1 creates a DataSet with Database1DataSet name.
Now I want to update the DataBase with this code :

C++

private void saveButton_Click(object sender, RoutedEventArgs e)
{
    Database1DataSet myDataSet = new Database1DataSet();
    
    DataRow myDataRow = myDataSet.Tables["events"].NewRow();//on this line 
    myDataRow["event"] = "new text";
    myDataRow["date"] = mdCalendar.Time();
    myDataSet.Tables["events"].Rows.Add(myDataRow);

}

but this error has occurred :

Object reference not set to an instance of an object.

I'm sure the events exist in the DataBase.
What's wrong with it ?
Thanks in advance.

Re: DataSet Problem !

Wendelius6-Jan-09 2:47

Wendelius

6-Jan-09 2:47

Mohammad Dayyan wrote:
Database1DataSet myDataSet = new Database1DataSet();

Since you're creating a new, fresh dataset it may not have any tables in it (depending what you do in the constructor for Database1DataSet).

Without knowing your program logic most likely you should refer to an existing dataset which is defined somewhere in the program (at form level, a static object etc.)

The need to optimize rises from a bad design.My articles[^]

Re: DataSet Problem !

Jason C Bourne7-Jan-09 11:21

Jason C Bourne

7-Jan-09 11:21

You create a .Net DataSet in memory, and immediately you do:

myDataSet.Tables["events"].NewRow();//on this line

Don't you think that your forgot to create a DataTable called "events" ? Wink | ;-)

You are not accessing any Database here, you are instantiating a DataSet object and you attempt to access a DataTable that you don't have created. I suggest reading some article about ADO.Net, it explains very well how to connect to a Database, retrieve data from it encaspulated in a DataSet, update data and stuff like that.

Jean-Christophe Grégoire

Re: DataSet Problem !

Mohammad Dayyan7-Jan-09 23:27

Mohammad Dayyan

7-Jan-09 23:27

Thanks.
I've done it.

//table's name = eventsTable
Database1DataSetTableAdapters.eventsTableTableAdapter eventsTableTableAdapte = 
	new WpfApplication1.Database1DataSetTableAdapters.eventsTableTableAdapter();
Database1DataSet.eventsTableDataTable eventsTableDataTable = 
	new Database1DataSet.eventsTableDataTable();
eventsTableTableAdapte.Fill(eventsTableDataTable);
DataRow newDataRow = eventsTableDataTable.NewRow();
newDataRow["event"] = "event8" ;
newDataRow["date"] = 654982;
eventsTableDataTable.Rows.Add(newDataRow);
eventsTableTableAdapte.Update(eventsTableDataTable);

eventsTableTableAdapte.Dispose();
eventsTableDataTable.Dispose();

But I don't know why the changes haven't applied to the DataBase Confused | :confused:

Could you guide me ?

Disable/enable CollectionEditor properties?

kanchoette6-Jan-09 2:35

kanchoette

6-Jan-09 2:35

Can CollectionEditor properties be set programmatically please?

For example, I have two CollectionEditor properties 'AutoWidth'(bool) and 'ColumnWidth'(int).

If 'AutoWidth' is set to 'True' then I would like the property 'Column Width' to be disabled.

Re: Disable/enable CollectionEditor properties?

Henry Minute6-Jan-09 2:58

Henry Minute

6-Jan-09 2:58

I don't know if this can be done but I am sure that someone else will provide help if it can.
What I would say is that if you look at similar properties in the inbuilt controls e.g. AutoSize for labels, textboxes etc. they do not disable other properties when set. The program logic just ignores changes to the irrelevant properties if they (AutoSize) are set to true.
So in the setter for ColumnWidth only apply setting if AutoWidth is false.

something like:

public int ColumnWidth
{
    get
    {
        return this.columnWidth;
    }

    set
    {
        if (!this.autoSize)
        {
            if (this.columnWidth != value)
            {
                this.columnWidth = value;
                this.Invalidate();
            }
        }
    }
}

Hope this helps.

Honi soit qui mal y pongs - Evil to he who thinks it stinks

Re: Disable/enable CollectionEditor properties?

kanchoette6-Jan-09 3:32

kanchoette

6-Jan-09 3:32

A good point well made.

Much appreciated.

As an aside, I notice that items like 'DataSource' in component properties are intially set to '(none)'. As yet, I have not figured out how to do this for my own (custom) properties. If anyone knows this I would be grateful for an educational 'nudge'.

Re: Disable/enable CollectionEditor properties?

Henry Minute6-Jan-09 4:25

Henry Minute

6-Jan-09 4:25

Google, or otherwise search) for info on the AttributeProvider attribute.

Come back if still no joy.

Honi soit qui mal y pongs - Evil to he who thinks it stinks

Re: Disable/enable CollectionEditor properties?

kanchoette6-Jan-09 4:30

kanchoette

6-Jan-09 4:30

Many thanks for that tip.

I also found this on my cyber travels

http://www.dslreports.com/forum/r18916156-C-Howto-disable-design-time-component-items[^]

which may be of use to others - hope it is Smile | :)

ShowBalloonTip of notifyicon not working

Tridip Bhattacharjee6-Jan-09 2:08

Tridip Bhattacharjee

6-Jan-09 2:08

i have developed a apps and in that apps a timer is there and i am showing ShowBalloonTip repeatedly from a timer method but the problem is ShowBalloonTip not showing. my timer elapsed time is 30 seconds.

from my timer tick method i have written code like

objNotifyer.Text = "MyMessage";
objNotifyer.ShowBalloonTip(1, "Info", "MyMessage", ToolTipIcon.Info);

i just can not understand why balloon is not showing. so please guide me regarding this and if possible then tell me how to write the code which will repeatedly show the balloon message from my timer tick method. please help.

tbhattacharjee

Re: ShowBalloonTip of notifyicon not working

Wendelius6-Jan-09 2:19

Wendelius

6-Jan-09 2:19

Try adding objNotifyer.Visible = true before ShowBalloonTip.

The need to optimize rises from a bad design.My articles[^]

Panels - Changing their width and dealing with the Horizontal Scroll Bar

Matthew Klein6-Jan-09 2:07

Matthew Klein

6-Jan-09 2:07

Hello All!

I have created a control that inherits from a Panel. My control has a method, UpdateControls() that repositions all of its child controls to where they need to be after they’ve been resized.

Sometimes the resizing causes the Vertical and Horizontal scroll bars to appear. I want the Vertical, but not the Horizontal, so at the end of the UpdateControls() method my control checks to see if the Vertical scroll is visible, and if it is, it increases its width so the Horizontal scroll bar isn’t needed.

protected void UpdateControls()
{
    this.SuspendLayout();

    int LastTop = this.AutoScrollPosition.Y;
    foreach (Control ic in _controls)
    {
        ic.Top = LastTop;
        LastTop = ic.Bottom + 5;
    }

    this.ResumeLayout(true);

    if (this.Width != this.NeededWidth)
    {
        this.Width = NeededWidth;
    }
}

public int NeededWidth
{
    get
    {
        if (this.VScroll)
            return _MaxWidth + 17;
        else
            return _MaxWidth;
    }
}

However, the form that contains my control isn’t updated properly. It seems to lag behind by one UpdateControls() call. It seems as though the resize of my control isn’t taking place until after all of the painting is done.

I’ve tried calling this.parent.Invalidate(true) and this.parent.Refresh() at the end of my UpdateControls() method, but neither force the new size to be used.

I found that by listening to the MyControl.SizeChanged event in MyForm and re-assigning the new width (after it had already been updated, thus triggering the SizeChanged event) will force the new size to be used, but MyControl gets drawn twice and it is noticeable on my form.

    _ItemsContainer = new MyControl();
    _ItemsContainer.SizeChanged += new EventHandler(_ItemsContainer_SizeChanged);
...
void _ItemsContainer_SizeChanged(object sender, EventArgs e)
{
    _ItemsContainer.Width = _ItemsContainer.NeededWidth;
}

How can I force the new size to be used so the Horizontal Scroll bars aren’t being drawn in my control?

Thank you!

Re: Panels - Changing their width and dealing with the Horizontal Scroll Bar

EliottA6-Jan-09 2:14

EliottA

6-Jan-09 2:14

Edit:

I had this problem when dealing with panels, what I did was keep all the panals inside my control visible = false, add the controls to each sub panel inside my panel and then reset the main panels height and width, then toggled all controls inside to visible=true as needed (it was a menu based off a data table, might not be exactly what you are looking for) then call the forms Update method after adding controls to my panels

Re: Panels - Changing their width and dealing with the Horizontal Scroll Bar

EliottA6-Jan-09 7:28

EliottA

6-Jan-09 7:28

After further auditing of my old code (your post had me refactor it a bit) I see that I set the visibility of the panel to false, added all the controls, resized it then set visibility to true, that was there is no visible horizontal / vertical bars appearing to the user as its visibility was off.

Let me know if I'm off base with this over here.

Re: Panels - Changing their width and dealing with the Horizontal Scroll Bar

#realJSOP6-Jan-09 8:31

#realJSOP

6-Jan-09 8:31

Why don't you just set the child control anchor properties correctly and be done with it?

"Why don't you tie a kerosene-soaked rag around your ankles so the ants won't climb up and eat your candy ass..." - Dale Earnhardt, 1997
-----
"...the staggering layers of obscenity in your statement make it a work of art on so many levels." - Jason Jystad, 10/26/2001

Re: Panels - Changing their width and dealing with the Horizontal Scroll Bar

Matthew Klein6-Jan-09 10:28

Matthew Klein

6-Jan-09 10:28

Setting the anchor to Left | Right worked.

Thanks everybody!

filling and adding to byte array [modified]

A4ad6-Jan-09 2:04

A4ad

6-Jan-09 2:04

Hi all,

i need to send a data message to a device every data message must have its header.

byte[] messageheader;
messageheader= new byte[10];
messageheader[0] = 0x16;
messageheader[1] = 0x01;
messageheader= BitConverter.GetBytes(01); // this must be divided into two bytes within the array
messagehd[3] = 02;
messageheader[4] = 00;
messageheader[5] = (byte)(message.Length);
serialPort1.Write(messageheader, 0, messageheader.Length);

now the BitConverter delete every thing, i think this is very simple, but I'm struggling with it Confused | :confused:

thanks in advance.

modified on Wednesday, January 7, 2009 3:31 AM

Re: filling and adding to byte array

Le centriste6-Jan-09 2:21

Le centriste

6-Jan-09 2:21

A4ad wrote:
messageheader= BitConverter.GetBytes(01); // this must be divided into two bytes within the array

Since BitConverter.GetBytes() returns an array, your messageheader gets reassigned, thus losing the reference created 3 lines above. What you need to do is:

byte[] messageheader = new byte[10];
messageheader[0] = 0x16;                
messageheader[1] = 0x01;
Array.Copy(BitConverter.GetBytes(01), 0, messageheader, 2, 2); // Copy 2 bytes to positions 2 and 3.
messagehd[4] = 02; // NOTE: If you need to copy 2 bytes from above, your previous code would be overriding the second one. Change the index.
messageheader[5] = 00;     
messageheader[6] = (byte)(message.Length);
serialPort1.Write(messagehd, 0, messagehd.Length);

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