C# Discussion Boards - CodeProject

12-Apr-06 8:13

Please help this. There are 2 errors at Thread creation.
I'd like to pass ArrayList to thread.

using System;<br />
using System.Threading;<br />
using System.Collections;<br />
namespace ConsoleApplication2<br />
{<br />
	class Program<br />
<br />
	{<br />
		static object lockObject;<br />
<br />
		static void Main(string[] args)<br />
<br />
		{	 <br />
<br />
<br />
			ArrayList space = new ArrayList();	<br />
<br />
			for (int i = 1; i <= 10  ; i++)<br />
			{<br />
				space.Add(i);<br />
			 <br />
			}		<br />
<br />
			lockObject = new object();				 <br />
			 <br />
<br />
 			Thread t1 = new Thread(new ParameterisedThreadStart(AccessData));		      	                t1.Start(space);<br />
<br />
			Thread.Sleep(20*1000);<br />
<br />
		}<br />
<br />
	 <br />
		<br />
		public static void AccessData(object param)<br />
		{<br />
//			Thread.CurrentThread.IsBackground = true;<br />
			 <br />
			ArrayList list = (ArrayList)param;<br />
					<br />
			lock (lockObject)<br />
			{<br />
				Random rand = new Random();<br />
		<br />
				int x = rand.Next(list.Count);<br />
				list.Remove(x);<br />
				Console.WriteLine("x = " + x);<br />
						<br />
				int y = rand.Next(list.Count);<br />
				list.Remove(y);<br />
				Console.WriteLine("y = " + y);<br />
		<br />
				int newNumber = x + y;<br />
				Console.WriteLine("newNumber = " + newNumber);<br />
		<br />
				list.Add(newNumber);<br />
		<br />
		<br />
		<br />
				foreach (int inte in list)<br />
					Console.WriteLine(inte);<br />
		<br />
			}<br />
						<br />
		 <br />
		 <br />
		}<br />
			<br />
	}<br />
}<br />

eric

Judah Gabriel Himango12-Apr-06 8:26

12-Apr-06 8:26

What are the 2 errors?

Which version of the .NET framework are you running? (ParameterizedThreadStart is only in version 2.0 or higher)

eric_tran12-Apr-06 8:37

12-Apr-06 8:37

Ah

The type or namespace name ParameterisedThreadStart could not be found

I use 1.1

So how I can get rid of that.

Please help

eric

Dan Neely12-Apr-06 8:55

Dan Neely

12-Apr-06 8:55

get VS05 and use the 2.0 framework or find the 1.1 equivilant to the code.

eric_tran12-Apr-06 8:58

12-Apr-06 8:58

Well, I just got the same errors in VS.Net 2005

So it's not because of the framework version then

Please help

eric

Judah Gabriel Himango12-Apr-06 9:06

12-Apr-06 9:06

Make sure you've got

using System.Threading;

at the top of your .cs file where you use ParameterizedThreadStart.

You can read more about it here[^].

There are several alternatives though, including some that work on all .NET versions. Here's another way of starting a new thread, using Delegate.BeginInvoke:

public class MyClass
{
    public delegate void FunctionThatTakesAnArrayList(ArrayList argument);

    ...

    void StartTheThread()
    {
        FunctionThatTakesAnArrayList function = ThreadedArrayListUsage;
        function.BeginInvoke(myArrayList, null, null); // BeginInvoke will cause the method to be executed on a new thread.
    }

    void ThreadedArrayListUsage(ArrayList list)
    {
        // use it here
    }

}

Here's another way, using the .NET thread pool:

void StartTheThread()
{
    System.Threading.ThreadPool.QueueUserWorkItem(ThreadedArrayListUsage, myArrayList);
}

void ThreadedArrayListUsage(object state)
{
    ArrayList list = (ArrayList)state;
}

Tech, life, family, faith: Give me a visit.
I'm currently blogging about: I luv teh choco
The apostle Paul, modernly speaking: Epistles of Paul

Judah Himango

eric_tran12-Apr-06 9:08

12-Apr-06 9:08

Thanks so much

I'm doing now

eric

Tooltip does not show up

smurfy3412-Apr-06 7:35

smurfy34

12-Apr-06 7:35

Hi:

I selected Tooltip from the toolbox and clicked on the form and then for the contriols I want a tooltip, I went to the properties and entered the text I want to show (I tried with an without double quotes).

But I cant get the tooltip to show up. Please could you tell me if I am missing doing something?

Thanks, smurfy

Manas Bhardwaj12-Apr-06 23:15

Manas Bhardwaj

12-Apr-06 23:15

Hey Smurfy,
Are you talking about Windows or Web application?

Manas

smurfy3414-Apr-06 4:19

smurfy34

14-Apr-06 4:19

Hi Manas:

this is for a windows application.

Thanks, smurfy

lvanerstrom14-Apr-06 8:18

lvanerstrom

14-Apr-06 8:18

I've had various issues with tooltips before as well. What I've found is that if I don't set the tooltip text at form load then the tooltip will never show up. I've often found that I have to set generic text and then set the tooltip active property to false until sometime later in my code I set the text I need and mark the tooltip active again. Using this method works every time. Maybe a bug in c# but i'm not sure.

Oh, and if you need the tooltip to show up even if the control it's bound to isn't the active control of the form then set it's show always property to true.

Synchronization thread help?

smurfy3414-Apr-06 9:14

smurfy34

14-Apr-06 9:14

thank you I will try that out.

Regards, smurfy

eric_tran12-Apr-06 7:28

12-Apr-06 7:28

Please help me

How can I call pass the ArrayList to 2 threads as parameter, and Synchronization thread
This is my code. My coding is not good, please help me

static object lockObject;

static void Main(string[] args)

{

ArrayList space = new ArrayList();

for (int i = 1; i <= 10 ; i++)
{
space.Add(i);

}

lockObject = new object();

lock (lockObject)
{
Thread t1 = new Thread(new ThreadStart(AccessData));
t1.Start();
}

lock (lockObject)
{
Thread t2 = new Thread(new ThreadStart(AccessData));
t2.Start();
}

Thread.Sleep(20*1000);

}

public static void AccessData(ArrayList arr)
{
// Thread.CurrentThread.IsBackground = true;

Random rand = new Random();

int x = rand.Next(space.Count);
space.Remove(x);
Console.WriteLine("x = " + x);

int y = rand.Next(space.Count);
space.Remove(y);
Console.WriteLine("y = " + y);

int newNumber = x + y;
Console.WriteLine("newNumber = " + newNumber);

space.Add(newNumber);

foreach (int inte in space)
Console.WriteLine(inte);

}

eric

Judah Gabriel Himango12-Apr-06 7:43

12-Apr-06 7:43

1. Locks are meant to be used inside the threaded code, not outside where you begin the thread. (In other words, use locks inside your AccessData method, not where you start the thread.)

2. You can start a thread with a parameter using something like this:

ParameterizedThreadStart threadStart = MyFunction;
Thread myThread = new Thread(threadStart);
myThread.Start(myArrayList);
...

void MyFunction(object parameter)
{
    ArrayList list = (ArrayList)parameter;
    // Use the list here. Be sure to lock it before using it.
}

3. Next time, use the <pre> tag around the code you post on this forum to preserve formatting.

Tech, life, family, faith: Give me a visit.
I'm currently blogging about: I luv teh choco
The apostle Paul, modernly speaking: Epistles of Paul

Judah Himango

eric_tran12-Apr-06 8:11

12-Apr-06 8:11

Please help this. There are 2 errors down

using System;<br />
using System.Threading;<br />
using System.Collections;<br />
namespace ConsoleApplication2<br />
{<br />
	class Program<br />
<br />
	{<br />
		static object lockObject;<br />
<br />
		static void Main(string[] args)<br />
<br />
		{	 <br />
<br />
<br />
			ArrayList space = new ArrayList();	<br />
<br />
			for (int i = 1; i <= 10  ; i++)<br />
			{<br />
				space.Add(i);<br />
			 <br />
			}		<br />
<br />
			lockObject = new object();				 <br />
			 <br />
<br />
//error			Thread t1 = new Thread(new ParameterisedThreadStart(AccessData));		//error 	 	t1.Start(space);<br />
<br />
			Thread.Sleep(20*1000);<br />
<br />
		}<br />
<br />
	 <br />
		<br />
		public static void AccessData(object param)<br />
		{<br />
//			Thread.CurrentThread.IsBackground = true;<br />
			 <br />
			ArrayList list = (ArrayList)param;<br />
					<br />
			lock (lockObject)<br />
			{<br />
				Random rand = new Random();<br />
		<br />
				int x = rand.Next(list.Count);<br />
				list.Remove(x);<br />
				Console.WriteLine("x = " + x);<br />
						<br />
				int y = rand.Next(list.Count);<br />
				list.Remove(y);<br />
				Console.WriteLine("y = " + y);<br />
		<br />
				int newNumber = x + y;<br />
				Console.WriteLine("newNumber = " + newNumber);<br />
		<br />
				list.Add(newNumber);<br />
		<br />
		<br />
		<br />
				foreach (int inte in list)<br />
					Console.WriteLine(inte);<br />
		<br />
			}<br />
						<br />
		 <br />
		 <br />
		}<br />
			<br />
	}<br />
}<br />

eric

Judah Gabriel Himango12-Apr-06 8:25

12-Apr-06 8:25

eric_tran wrote:
Please help this. There are 2 errors down

Please clarify. I don't know what you mean by "2 errors down". Confused | :confused:

Tech, life, family, faith: Give me a visit.
I'm currently blogging about: I luv teh choco
The apostle Paul, modernly speaking: Epistles of Paul

Judah Himango

eric_tran12-Apr-06 8:29

12-Apr-06 8:29

Sorry Judah

There are 2 errors at the Thread Creation and Start lines

Please help

eric

Judah Gabriel Himango12-Apr-06 9:07