C#

George_George wrote:

Some URL representations, like "www.google.com" is not legal

DaveyM69 wrote:

You need to decide yourself what you expect and check/format it as needed.

manju#123 wrote:

...It is giving Debug Error....

Simon Stevens wrote:

Post the full error details and stack.

Megidolaon wrote:

Does that mean normal variables are cached and to optimize speed, the cached value is used unless the variable is changed in the current thread?

Megidolaon wrote:

And volatile means, that no cached values are used but before every operation, the value of the variable is read again?

Megidolaon wrote:

BUT, what about larger variables, like long or even objects?
Wouldn't it still be possible that while one thread reads the first byte of a long, another thread writes the second byte?

class Program
{
    //global variable accessible by all threads
    static List<string> list = new List<string>();
     
    static void Main(string[] args)
    {
        Thread t1 = new Thread(new ThreadStart(DoSomething));
        Thread t2 = new Thread(new ThreadStart(DoSomethingElse));

        //start thread t2, then t1
        t2.Start();
        t1.Start();
        Console.ReadLine();
    }

   //Thread 1's work
    static private void DoSomething()
    {
            //wait until thread 2 finished locking
            Thread.Sleep(13);
            for (int i = 0; i < 100; i++)
            {
                //first add "1" to the list and then write it to the console
                list.Add("1");
                Console.WriteLine("1");
                //checks if this thread accesses the list before t2 finished its work
                if (list.Count< 100 && list.Contains("2"))
                {
                    Console.WriteLine("FIRST LOCK BREACHED!");
                    break;
                }
            }
           //writes thread number and count to the console
           Console.WriteLine("1-Count: " + list.Count.ToString());
    }

   //Thread 2's work 
   static private void DoSomethingElse()
   {
       lock (list)
       {
           for (int i = 0; i < 100; i++)
           {
               //first add "2" to the list and then write it to the console
               list.Add("2");
               Console.WriteLine("2");
                
               //checks if thread t accessed the list before the lock was released
               if (list.Contains("1"))
               {
                   Console.WriteLine("SECOND LOCK BREACHED!");
                   break;
               }
           }
           //writes thread number and count to the console
           Console.WriteLine("2-Count: " + list.Count.ToString());    
       }
 }</string></string>

...
2
1
FIRST LOCK BREACHED
1-Count: 19
SECOND LOCK BREACHED
2-Count:19

Megidolaon wrote:

This will produce random output, it seems the threads get different time slices every time I execute the program, how come?

Megidolaon wrote:

This is confusing me, because I thought lock actually blocks other threads. However that is apparently not the case.

Admin887 wrote:

i did this code but it pop a exception:

"Update requires a valid InsertCommand when passed DataRow collection with new rows"

What i need t do? and where?