Problems when going from framework 1.1 to 2.0 beta - C# Discussion Boards

Re: How to know if a place holder is empty

Rob Graham3-Mar-05 15:28

3-Mar-05 15:28

Example.Controls.Count

Anger is the most impotent of passions. It effects nothing it goes about, and hurts the one who is possessed by it more than the one against whom it is directed.
Carl Sandburg

Re: How to know if a place holder is empty

see074-Mar-05 9:28

see07

4-Mar-05 9:28

Thanks you Rob, also work with Example.HasControls();

El hombre que tiene amigos debe mostrarse amigo...

sorting datagrid with empty rows

Mc Fetto3-Mar-05 9:32

Mc Fetto

3-Mar-05 9:32

I have datagrid that I'm filling with rows, if the rows don't fill up the size of the grid, then I'm adding new empty rows from my dataview in my derived datagrid. The problems that comes up is that when im sorting the columns the empty rows are also sorted (not the last one, and i don't know why the last one is not sorted). Qestion: can i somehow sort the filled rows and just letting the empty (DBNULL) just be in the bottom of my grid?

Selection Color

Radgar3-Mar-05 7:39

Radgar

3-Mar-05 7:39

I wonder how I can change the highlight color of a ListView control when an item is selected. Thanks in advance.

Radgar
"Imagination is more important than knowledge." - Albert Einstein

Calculations on Dataset Urgent Please help

nishant.gogia3-Mar-05 7:37

nishant.gogia

3-Mar-05 7:37

Hi,
I have a table in a Dataset that contains rows for many products. Each row contains Rate of that product. I want to create a new table which would contain Rate of all products discounted at 20%. Is it possible. If yes how?.
My preferred approach is rather then reading each row and then getting the rate i want to apply this dicount for all products at one time.

Nishant

Re: Calculations on Dataset Urgent Please help

Kodanda Pani3-Mar-05 16:17

Kodanda Pani

3-Mar-05 16:17

Hi Nishant,

You can DataColum.Expression property for doing this. This allows you to calculate the values of a colum.

1) Create a new colum with a proper data type.
2) Set the expression property of that coloum . (Ex "rate * 0.8")
3) Add this colum to the table.

The new column is filled with the calculated value.

Hope this will help you.

Regards
SGS

Re: Calculations on Dataset Urgent Please help

nishant.gogia3-Mar-05 17:07

nishant.gogia

3-Mar-05 17:07

Thanks a lot, it worked.
But one more thing can i have this column in some other table...

Problems when going from framework 1.1 to 2.0 beta

Talal Sultan3-Mar-05 7:23

Talal Sultan

3-Mar-05 7:23

Hi people,

I have a running small windows forms application on 1.0 and 1.1, but when I use the code on 2.0 beta, it says that the thread cannot access an object that it hasn't created Confused | :confused:

. Can anyone check this out for me please? I have 2 files, one called Main.cs, which is the main program and then I have Ticker.cs which is another window class called from Main. I will post below the whole code for both files, if anyone has any clue about that.
I am using SharpDevelop for 1.1 and Visual C# Express 2005 beta for 2.0

Main.cs

<br />
<br />
using System;<br />
using System.Drawing;<br />
using System.Collections;<br />
using System.ComponentModel;<br />
using System.Windows.Forms;<br />
using System.Data;<br />
using System.Threading;<br />
<br />
<br />
namespace Exercice1<br />
{<br />
	/// <summary><br />
	/// Summary description for Form1.<br />
	/// </summary><br />
	public class Form1 : System.Windows.Forms.Form<br />
	{<br />
		private System.Windows.Forms.Label label1;<br />
		private System.Windows.Forms.Label lblText;<br />
		private System.Windows.Forms.Button btnClose;<br />
		private System.Windows.Forms.Timer timer;<br />
		private System.ComponentModel.IContainer components;<br />
		private System.Windows.Forms.ProgressBar progressBar1;<br />
<br />
<br />
<br />
		/// <summary><br />
		/// Required designer variable.<br />
		/// </summary><br />
		//private System.ComponentModel.Container components = null;<br />
<br />
		public Form1()<br />
		{<br />
			//<br />
			// Required for Windows Form Designer support<br />
			//<br />
			InitializeComponent();<br />
<br />
			//<br />
			// TODO: Add any constructor code after InitializeComponent call<br />
			//<br />
		}<br />
<br />
		/// <summary><br />
		/// Clean up any resources being used.<br />
		/// </summary><br />
		protected override void Dispose( bool disposing )<br />
		{<br />
			if( disposing )<br />
			{<br />
				if (components != null) <br />
				{<br />
					components.Dispose();<br />
				}<br />
			}<br />
			base.Dispose( disposing );<br />
		}<br />
<br />
		#region Windows Form Designer generated code<br />
		/// <summary><br />
		/// Required method for Designer support - do not modify<br />
		/// the contents of this method with the code editor.<br />
		/// </summary><br />
		private void InitializeComponent()<br />
		{<br />
<br />
			this.components = new System.ComponentModel.Container();<br />
			this.timer = new System.Windows.Forms.Timer(this.components);<br />
			this.label1 = new System.Windows.Forms.Label();<br />
			this.lblText = new System.Windows.Forms.Label();<br />
			this.btnClose = new System.Windows.Forms.Button();<br />
			this.progressBar1 = new System.Windows.Forms.ProgressBar();<br />
			this.SuspendLayout();<br />
			// <br />
			// label1<br />
			// <br />
			this.label1.Font = new System.Drawing.Font("Microsoft Sans Serif", 9.75F, System.Drawing.FontStyle.Bold, System.Drawing.GraphicsUnit.Point, ((System.Byte)(0)));<br />
			this.label1.Location = new System.Drawing.Point(16, 16);<br />
			this.label1.Name = "label1";<br />
			this.label1.Size = new System.Drawing.Size(264, 23);<br />
			this.label1.TabIndex = 0;<br />
			this.label1.Text = "Welcome";<br />
			// <br />
			// lblText<br />
			// <br />
			this.lblText.Location = new System.Drawing.Point(16, 56);<br />
			this.lblText.Name = "lblText";<br />
			this.lblText.Size = new System.Drawing.Size(264, 23);<br />
			this.lblText.TabIndex = 1;<br />
			this.lblText.Text = "Loading XYZ...";<br />
			// <br />
			// btnClose<br />
			// <br />
			this.btnClose.Location = new System.Drawing.Point(208, 128);<br />
			this.btnClose.Name = "btnClose";<br />
			this.btnClose.TabIndex = 2;<br />
			this.btnClose.Text = "Cancel";<br />
			this.btnClose.Click += new System.EventHandler(this.btnClose_Click);<br />
			// <br />
			// progressBar1<br />
			// <br />
			this.progressBar1.Location = new System.Drawing.Point(16, 96);<br />
			this.progressBar1.Name = "progressBar1";<br />
			this.progressBar1.Size = new System.Drawing.Size(264, 23);<br />
			this.progressBar1.Step = 1;<br />
			this.progressBar1.Minimum=0;<br />
			this.progressBar1.Maximum=20;<br />
			this.progressBar1.TabIndex = 3;<br />
			// <br />
			// timer<br />
			// <br />
			this.timer.Enabled = true;<br />
			this.timer.Interval = 300;<br />
			this.timer.Tick += new System.EventHandler(this.timer_Tick);<br />
			// <br />
			// Form1<br />
			// <br />
			this.AutoScaleBaseSize = new System.Drawing.Size(5, 13);<br />
			this.ClientSize = new System.Drawing.Size(294, 175);<br />
			this.Controls.AddRange(new System.Windows.Forms.Control[] {<br />
																		  this.progressBar1,<br />
																		  this.btnClose,<br />
																		  this.lblText,<br />
																		  this.label1});<br />
			this.FormBorderStyle = System.Windows.Forms.FormBorderStyle.FixedDialog;<br />
			this.Name = "SplashForm";<br />
			this.Text = "Loading MyApp...";<br />
			this.Load += new System.EventHandler(this.SpashForm_Load);<br />
			this.ResumeLayout(false);<br />
<br />
		}<br />
		#endregion<br />
	<br />
		private void btnClose_Click(object sender, System.EventArgs e)<br />
		{<br />
			this.DialogResult = DialogResult.Cancel;<br />
			this.Close();<br />
		}<br />
		<br />
		private void timer_Tick(object sender, System.EventArgs e)<br />
		{<br />
			if (progressBar1.Value != progressBar1.Maximum)<br />
			{<br />
				progressBar1.PerformStep();<br />
					<br />
			}<br />
			else<br />
			{<br />
				this.timer.Tick -= new System.EventHandler(this.timer_Tick);<br />
				Ticker t1 = new Ticker();<br />
				t1.Show();<br />
				this.Hide();<br />
			}<br />
				<br />
		}<br />
<br />
		private void SpashForm_Load(object sender, System.EventArgs e)<br />
		{<br />
			if (progressBar1.Value == progressBar1.Maximum)<br />
			{<br />
				<br />
			}<br />
		}<br />
		protected override void OnClosing(CancelEventArgs e) <br />
		{<br />
			this.Dispose();<br />
			Environment.Exit(0);<br />
<br />
		}<br />
		/// <summary><br />
		/// The main entry point for the application.<br />
		/// </summary><br />
		[STAThread]<br />
		static void Main() <br />
		{<br />
			Application.Run(new Form1());<br />
		}<br />
	}<br />
<br />
	<br />
}<br />
<br />

Ticker.cs

<br />
using System;<br />
using System.Windows.Forms;<br />
using System.ComponentModel;<br />
using System.Drawing;<br />
using System.Threading;<br />
using System.IO;<br />
<br />
namespace Exercice1 {<br />
	<br />
	public class Ticker : Form {<br />
		<br />
		Label label1, label2;<br />
		<br />
		String[] newsItems =<br />
		{ "Safest Aerobic Machine Launched",<br />
			"First Dog Cloning Is Only Days Away",<br />
			"Reviving the Extinct Tasmanian Tiger" };<br />
		<br />
		String[] businessItems =<br />
		{ "FirstMeasure Software to Go Nasdaq",<br />
			"MFMF Directors To Meet For The First Time",<br />
			"First Sign of Economic Recovery Finally At Sight",<br />
			"Euro Hits Record Low (Again)" };<br />
		<br />
		<br />
<br />
		public Thread NewsThread,BusinessThread;<br />
		<br />
		//  public static void Main() {<br />
		//    Ticker ticker = new Ticker();<br />
		//    Application.Run(ticker);<br />
		//  }<br />
		<br />
		public Ticker() {<br />
			Initialize();<br />
			StartThread();<br />
		}<br />
		#region Windows Form Designer generated code<br />
		/// <summary><br />
		/// Required method for Designer support - do not modify<br />
		/// the contents of this method with the code editor.<br />
		/// </summary>		<br />
		private void Initialize() {<br />
			this.Height = 100;<br />
			<br />
			label1 = new Label();<br />
			label2 = new Label();<br />
			<br />
			label1.Width = 280;<br />
			label1.Height = 30;<br />
			label1.Location = new Point(1, 10);<br />
			label1.TextAlign = ContentAlignment.MiddleRight;<br />
			<br />
			label2.Width = 280;<br />
			label2.Height = 30;<br />
			label2.Location = new Point(1, 40);<br />
			<br />
			this.Controls.Add(label1);<br />
			this.Controls.Add(label2);<br />
		}<br />
		#endregion<br />
		<br />
		private void StartThread() {<br />
			<br />
			NewsThread = new Thread(new ThreadStart(MoveLeft));<br />
			BusinessThread = new Thread(new ThreadStart(MoveRight));<br />
			NewsThread.Start();<br />
			BusinessThread.Start();<br />
			//MoveLeft();<br />
		}<br />
		<br />
		private  void MoveLeft() {<br />
			// <br />
			string labelText;<br />
			while(true)<br />
			{<br />
<br />
				foreach(string item in newsItems)<br />
				{<br />
					labelText = item;<br />
					label1.Text=labelText;<br />
<br />
					for (int i=280;i>1;i--)<br />
					{<br />
						label1.Location = new Point(i, 10);<br />
					<br />
						Thread.Sleep(10);<br />
					}<br />
<br />
					Thread.Sleep(500);<br />
				}<br />
			}<br />
		}<br />
		<br />
		private void MoveRight() <br />
		{<br />
			string labelText;<br />
<br />
			while(true)<br />
			{<br />
				foreach(string item in businessItems)<br />
				{<br />
					labelText = item;<br />
					label2.Text="";<br />
					int textLength = labelText.Length;<br />
<br />
					for (int i=0;i<textLength;i++)<br />
					{<br />
						label2.Text+=labelText[i];<br />
						Thread.Sleep(50);<br />
					}<br />
				<br />
<br />
					Thread.Sleep(500);<br />
				}<br />
			}<br />
		}<br />
		<br />
		protected override void OnClosing(CancelEventArgs e) {<br />
			<br />
			NewsThread.Abort();<br />
			BusinessThread.Abort();<br />
			this.Dispose();<br />
			Environment.Exit(0);<br />
<br />
		}<br />
		<br />
		<br />
	}<br />
}<br />
<br />

Thank you!
Talal

"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning."
--Rich Cook

Re: Problems when going from framework 1.1 to 2.0 beta

Judah Gabriel Himango3-Mar-05 7:55

Judah Gabriel Himango

3-Mar-05 7:55

This is most likely occurring in your tick event handler. Basically, Windows Forms controls (like your progress bar), and indeed all Win32 common controls, cannot be accessed on a thread other than the thread that created the control. Check out MSDN for Control.Invoke and Control.BeginInvoke.

Tech, life, family, faith: Give me a visit.
I'm currently blogging about: Lies of Our Fathers: A Must-Know About Lent
Judah Himango

Re: Problems when going from framework 1.1 to 2.0 beta

Talal Sultan3-Mar-05 11:24

Talal Sultan

3-Mar-05 11:24

thanks!

I will look into that.

Talal

"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning."
--Rich Cook

Re: Problems when going from framework 1.1 to 2.0 beta

S. Senthil Kumar3-Mar-05 7:59

S. Senthil Kumar

3-Mar-05 7:59

You've broken one of the basic rules of Windows UI programming. Only the thread that created the UI can modify the UI. .NET 1.1 doesn't report any exception but I bet you wouldn't have achieved the effect you wanted. .NET 2.0 immediately throws an exception if you try to modify the UI from some other thread.

You'll have to use Invoke/BeginInvoke to marshal the method call on the UI thread.

Regards
Senthil
My Blog

Re: Problems when going from framework 1.1 to 2.0 beta

Talal Sultan3-Mar-05 11:30

Talal Sultan

3-Mar-05 11:30

Hi,

well, the weird thing is that it is actually achieving what I want...After the progressbar finishes, the first window is hidden and the other window opens and you have 2 threads created. One is the right method to move text from right to left and the other is the left method..and they loop forever.

I will try looking into that invoke thing, although I have no idea how it works.

thanks for the tip, I appreciate it Smile | :)

Talal

"Programming today is a race between software engineers striving to build bigger and better idiot-proof programs, and the Universe trying to produce bigger and better idiots. So far, the Universe is winning."
--Rich Cook

DateTime problem

Anonymous3-Mar-05 6:34

Anonymous

3-Mar-05 6:34

Hi everybody.

I'm retreiving a DateTime from MS sql server, on two different computers.
Both computers have the same definition in ControlPanel > Regional and language options, and same version of .Net (1.1).

When I cast the DateTime to string, (DateTime.ToString()), I get on computer #1 mm/dd/yyyy, while in computer #2 I get dd/mm/yyyy.

Where is the problem?

Thanks,
Yaakov

Re: DateTime problem

sreejith ss nair3-Mar-05 9:22

sreejith ss nair

3-Mar-05 9:22

I am not getting why it is showing differently. Just have a look at you regional settings agian.
And you can use string formats to get your date both date in one format .

DateTime.ToString("dd-MM-yyyy")<br />
 or<br />
 DateTime.ToString("dd-MMM-yyyy")<br />
 or<br />
 DateTime.ToString("MMM-dd-yyyy")

wiil help you out to get a common format for Dates.

Sreejith Nair
[ My Articles ]

Re: DateTime problem

Anonymous3-Mar-05 10:30

Anonymous

3-Mar-05 10:30

I know about the formats.

However, this doesn't solve my problem, since I can't modify the entire application.

Thanks anyway.

Yaakov

enybody Know...???

ABBASI_RA3-Mar-05 3:55

ABBASI_RA

3-Mar-05 3:55

hi i write a web application with c#.
it has some pages and thir controls such as:
validators , datagrid , datalist with template column
and they have thir event handler functions.

the application works correctly on local.
{ my system: [windows 2003 server ]}
but when i upload it to the host server , the events dont work correctly.
------------
site address:http://siteavval.com/WebVDir/MainGrps.aspx
error message for:
javascript__doPostBack('MainGrpsList$_ctl0$LBGrpShr','')

,.net security related problem

montu33773-Mar-05 3:46

montu3377

3-Mar-05 3:46

Hi,

Here i m facing one problem with .net console application.I am having one solution (.net project) now due to our requirement we had made one dll out of that project and then from one another console application i had called that dll.Now problem is that when i am running that another project of console application which is having my project dll ,it is giving the error of system.componentmodel.win32 application after running my console application.

Now Main thing is that one some machine our same application is running without error and on some machine it is givign error which i had describe above so after searching i found that this is error due to .net security now can anybody know how to give right of user which allows my console applicaiton to run without error?
where and how to give rights to user so my application run without errors?

montu3377

Re: ,.net security related problem

Judah Gabriel Himango3-Mar-05 6:39

Judah Gabriel Himango

3-Mar-05 6:39

Go into Control Panel, Administrative Tools, Microsoft .NET Framework wizards, Trust An Assembly, then specify your application and give it the necessary trust to run.

Tech, life, family, faith: Give me a visit.
I'm currently blogging about: Lies of Our Fathers: A Must-Know About Lent
Judah Himango

is there a concept of const function parameters?

feline_dracoform3-Mar-05 3:33

feline_dracoform

3-Mar-05 3:33

in C++ i can pass a function a const reference to an object. i find this is normally a good idea, since it assures me that the function will not make any changes to the objects state.

is there an equivalent concept in C#? if i understand C# correctly all instances of objects are references and initial experiments show they are passed as modifiable references.

i am trying to create a tree of objects (representing the sub directories on a CD-ROM), so that i can say to each child "this is your parent", passing a constant reference to its parent in its constructor. a child cannot alter its parent, so i want to enforce this concept in the code.

i have found a C# article on modifier keywords which led me to discover that i can have a read only object. but putting readonly before the parameter type does not compile Frown | :(

if there is no such concept, how do people express the concept "remember this object, but you cannot modify it?"

zen is the art of being at one with the two'ness

Re: is there a concept of const function parameters?

S. Senthil Kumar3-Mar-05 7:17

S. Senthil Kumar

3-Mar-05 7:17

There is no language support for const function parameters. For your case though, you can declare the parent field in the child class as readonly. That means that it can only be set in the constructor/field initializer. Like this

<br />
class Child : Node<br />
{<br />
   private readonly Node parent;<br />
<br />
   public Child(Node parent)<br />
   {<br />
      this.parent = parent;<br />
   }<br />
   public void SomeFunc()<br />
   {<br />
      parent = new Node(...); //won't compile<br />
   }<br />
}<br />

Regards
Senthil
My Blog

Dll Import ( C++ Dll) and the result array

Anonymous3-Mar-05 3:03

Anonymous

3-Mar-05 3:03

Hi,
I import a C++ Dll in my C# application.
First I call from C# a C++ function and then I get
a result set from the dll.
The result is a array with 3 dimensions.
How can I get access this array in C#.

Please help me !

Get fusing of two pixels

Anonymous3-Mar-05 2:11

Anonymous

3-Mar-05 2:11

I need to get a new pixel color starting by a green color and another one over this blue semi-transparent at 50%.
I've readed some articles on this forum but i need just 2 lines of code not warking with whole bitmaps.
I know it is a very simple stuff, but i don't know how fuse or join two pixels getting another colored pixel.

i've tried with
myColor.R = Color.Green.R & Color.Blue.R
myColor.G = Color.Green.G & Color.Blue.G
myColor.B = Color.Green.B & Color.Blue.B

it works but it fuse full blue on green, i need to fuse semitransparent blue instead.
Please help me.
thanks

Re: Get fusing of two pixels

leppie3-Mar-05 9:01

leppie

3-Mar-05 9:01

what about:

myColor.R = (Color.Green.R + Color.Blue.R)/2;
myColor.G = (Color.Green.G + Color.Blue.G)/2;
myColor.B = (Color.Green.B + Color.Blue.B)/2;

^{xacc-ide 0.0.15 now with C#, MSIL, C, XML, ASP.NET, Nemerle, MyXaml and HLSL coloring - Screenshots}

Re: Get fusing of two pixels

Sasuko3-Mar-05 11:53

Sasuko

3-Mar-05 11:53

Perfect Tnx : )

Where to store data?

chilberto3-Mar-05 0:40

chilberto

3-Mar-05 0:40

I was hoping other developers could give me some advice as to where to store my data! Previously I have always used classes to maintain information relating to the current process. If a background thread required additional information to process, I usually either passed the information in as a parameter or added properties to my thread class.

Recently I have become aware of CallContext and Thread.SetData. I am sure there are also other "places" that .Net provides for storing information relating to the current process/thread.

My question really is: could someone help me understand the scope and purpose of the different storage mechanisms provided by .Net and why you would use one over the other.

Thanks in advance.

-------------------------------------------------------------------
After some investigation, this is my understanding:
CallContext is visible to all theads where Thread data is only visible to the active thread.

I believe these mechanisms are available as a convenient way to gain access to objects and can be used to avoid the difficulties of making classes visible to eachother. I tend to use Class (static) level objects for this, but I can see in some cases (e.g., usertokens) CallContext would be useful.

- Jeff

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