How to Kill a Thread - C#

Posted 17 May. 2021 | 1 min read.

If you wish to terminate a thread in C#, you can use the Abort() method. Using Abort() with throw a ThreadAbortException, which will terminate the thread.

To show this in action, let's first create a thread:

using System;
using System.Threading;

class ThreadExample 
{
	public void MyThread()
	{
        for (int x = 0; x < 3; x++) 
        {
            Console.WriteLine(x);
        }
	}
}

class MainClass 
{
	public static void Main()
    {
		var obj = new ThreadExample();
		Thread thr = new Thread(new ThreadStart(obj.MyThread));

        Console.WriteLine("Start the thread");
		thr.Start();
		
		Console.WriteLine("Finished!");
	}
}
Start the thread
0
1
2
Finished!

If we call Abort() immediately after Start(), we can stop the thread from executing:

Console.WriteLine("Start the thread");
thr.Start();

Console.WriteLine("Abort the thread");
thr.Abort();

Console.WriteLine("Finished!");
Start the thread
Abort the thread
Finished!

It's important to note however, that if the thread that calls Abort() holds a lock, and the aborted thread requires that lock to be released, then a deadlock can occur.

C SharpBack-end