C# Program to display priority of Thread

In C#, thread priority determines how the operating system schedules threads for execution. The Priority property of the Thread class allows you to both view and set the priority of a thread. Thread priority is represented by the ThreadPriority enumeration.

Syntax

To get the current thread and display its priority −

Thread thread = Thread.CurrentThread;
ThreadPriority priority = thread.Priority;

To set a thread's priority −

thread.Priority = ThreadPriority.High;

ThreadPriority Enumeration Values

Displaying Current Thread Priority

Example

using System;
using System.Threading;

class MyClass {
   static void Main(string[] args) {
      Thread thread = Thread.CurrentThread;
      thread.Name = "My Thread";
      Console.WriteLine("Thread Name: {0}", thread.Name);
      Console.WriteLine("Thread Priority: {0}", thread.Priority);
      Console.WriteLine("Thread State: {0}", thread.ThreadState);
   }
}

The output of the above code is −

Thread Name: My Thread
Thread Priority: Normal
Thread State: Running

Setting and Displaying Different Thread Priorities

Example

using System;
using System.Threading;

class ThreadPriorityDemo {
   static void Main(string[] args) {
      Thread currentThread = Thread.CurrentThread;
      currentThread.Name = "Main Thread";
      
      Console.WriteLine("Default Priority: {0}", currentThread.Priority);
      
      // Set different priorities and display
      currentThread.Priority = ThreadPriority.Highest;
      Console.WriteLine("After setting Highest: {0}", currentThread.Priority);
      
      currentThread.Priority = ThreadPriority.Lowest;
      Console.WriteLine("After setting Lowest: {0}", currentThread.Priority);
      
      currentThread.Priority = ThreadPriority.AboveNormal;
      Console.WriteLine("After setting AboveNormal: {0}", currentThread.Priority);
      
      // Reset to normal
      currentThread.Priority = ThreadPriority.Normal;
      Console.WriteLine("Reset to Normal: {0}", currentThread.Priority);
   }
}

The output of the above code is −

Default Priority: Normal
After setting Highest: Highest
After setting Lowest: Lowest
After setting AboveNormal: AboveNormal
Reset to Normal: Normal

Creating Custom Threads with Priorities

Example

using System;
using System.Threading;

class CustomThreadDemo {
   static void ThreadMethod(object priority) {
      Thread current = Thread.CurrentThread;
      Console.WriteLine("Thread {0} - Priority: {1}", current.Name, current.Priority);
   }
   
   static void Main(string[] args) {
      Thread thread1 = new Thread(ThreadMethod);
      thread1.Name = "Thread1";
      thread1.Priority = ThreadPriority.High;
      
      Thread thread2 = new Thread(ThreadMethod);
      thread2.Name = "Thread2";  
      thread2.Priority = ThreadPriority.Low;
      
      Console.WriteLine("Starting threads with different priorities:");
      thread1.Start();
      thread2.Start();
      
      thread1.Join();
      thread2.Join();
      
      Console.WriteLine("Main thread priority: {0}", Thread.CurrentThread.Priority);
   }
}

The output of the above code is −

Starting threads with different priorities:
Thread Thread1 - Priority: High
Thread Thread2 - Priority: Low
Main thread priority: Normal

Conclusion

Thread priority in C# provides a way to influence thread scheduling by the operating system. Use the Priority property to get or set thread priority levels ranging from Lowest to Highest. Remember that priority is a suggestion to the OS scheduler, not an absolute guarantee of execution order.