??? ???? ??? ??? ? ?????? ????? ??? ??????. JavaScript? ????? ?? ?????? ? ?? ??? ??? ??? ? ????. ??? ???? ?? ?? ??? ??? ??? ??? ?? ???? ??? ??? ? ?? ?? ??? ??? ? ????.

Enter Web Workers – JavaScript ???? ????? ????? ????? ??? ? ?? ?????. Web Workers? ?? ????? ??? ??? ?????? ??????? ???? ???? ????? ?????.

?? ???? Web Worker? ? ??, ?? ?? ??, ?? ??? ?? ??? ???????. ????? ? ?? ?????? Web Worker? ???? ??? ???? ??? ?? ? ????.

---

? ???? ??????

Web Worker? ?? ???? ??? ??????? JavaScript ??? ??? ? ?? ??? ?? ? ????? ?????. ?, ??? ?????(UI)? ???? ?? ??? ??? ??? ? ?? ? ???? ?? ??????? ??? ? ????.

Web Workers? HTML5 ? API? ???? ???? ?? ?????? ?? ?????.

? ???? ?? ??:

1. ?????: ?? ????? ??? ?????.
2. ??? UI: ?? ??? ???? ?? UI? ???? ?????.
3. ???? ??: ???? ?? ???? ??? ?? ?? ?????? ?????.
4. ??? ?? ??: ??? ?? ???? ???? ?? ???? ??? ??? ?? ?????.

---

? ???? ??

Web Worker?? ? ?? ?? ??? ????.

1. ?? ???: ??? ????? ????? ???? ?? ??????.
2. ?? ???: ?? ?????? ??? ? ?? ??????.
3. ??? ??: ???? ??? ???? ???? ??(?: ?????? ? ?)? ????? ? ?? ???? ??? ??? ?????.

? ?????? ?? ????? ???? ?? ??? ??? ?????.

---

? ??? ???? ??

1. ?? ? ??? ???

? ???? ????? ?? ??? ????.

1??: ??? ???? ??

???? ?? ??? JavaScript ??? ????. ?? ??, Worker.js? ??? ????.

// worker.js
self.onmessage = function (event) {
  console.log('Message received from main thread:', event.data);

  // Perform heavy computation
  const result = event.data * 2;

  // Send result back to main thread
  self.postMessage(result);
};

??? onmessage ??? ???? ?? ???? ???? ???? ??? ? postMessage? ???? ??? ????.

2??: ?? ?????? ??? ??

?? JavaScript ??:

// main.js
if (window.Worker) {
  // Create a new Web Worker
  const myWorker = new Worker('worker.js');

  // Send data to the worker
  myWorker.postMessage(10);
  console.log('Message sent to worker');

  // Receive data from the worker
  myWorker.onmessage = function (event) {
    console.log('Message received from worker:', event.data);
  };

  // Handle worker errors
  myWorker.onerror = function (error) {
    console.error('Error from worker:', error.message);
  };
} else {
  console.log('Web Workers are not supported in this browser.');
}

??:

• ?? ????? ????? ?? 10? ????.
• ??? ??? ? ?? ??? 20? ??????.
• ??? ??? ?????.

---

2. ? ??? ??

???? ??? ???? ???? ???? ???? ???.

myWorker.terminate();
console.log('Worker terminated');

---

3. ??? ?? ??

Web Worker? ??? onerror ???? ???? ??? ? ????.

myWorker.onerror = function (error) {
  console.error('Error from worker:', error.message);
};

---

? ???? ?? ?? ?? ??

1. ??? ??

Web Worker? ??? ????? ??, ??? ??, ??? ????? ? CPU ???? ??? ???? ? ?????.

?: ???? ?? ??

??? ????(worker.js):

self.onmessage = function (event) {
  const num = event.data;
  const fib = (n) => (n <= 1 ? n : fib(n - 1) + fib(n - 2));
  const result = fib(num);
  self.postMessage(result);
};

?? ????(main.js):

const worker = new Worker('worker.js');
worker.postMessage(40); // Calculate the 40th Fibonacci number

worker.onmessage = function (event) {
  console.log('Result:', event.data);
  worker.terminate(); // Terminate the worker after use
};

---

2. ??? ??

Web Worker? ?? ???? ???? ??? ??? ???? ??? ?? ??? ??? ? ????.

---

3. ??? ??? ??

Web Workers? IoT ??????? WebSocket ??? ??? ?? ?? ??? ?? ??? ??? ??? ??????.

---

? ???? ??

Web Workers? ????? ? ?? ?? ??? ????.

• ??? ??:
  ???? DOM, ? ?? ?? ??? ?? ?? ??? ???? ? ????.

• ??? ?? ???:
  ? ???? ???? ???? ? ???? ?????.

• ??? ??:
  ?? ???? ??? ?? ??? ?? ??? ??? ? ????.

• ???? ??:
  Web Workers? ?? ?????? ????? ?? ??????? ???? ?? ? ????.

---

? ??? ???

Web Worker? ?????? ????? ??? ??? ?????. Web Worker?? ??? ??? ? ?? ?? ??? ?? ????.

---

? ??? ?? ?? ??

1. ??? ????? ??? ??

   • ??? ???? ???? ?? ?? ????? ???? ???.

2. ???? ?? ?? ??

   • ??? ??? ??? ??? ?? ??????.

3. ?????? ???? ???

   • ??? ?? ???? ???? ??? ??? ?????.

4. ???? ?? ?????? ??

   • ?? JavaScript ??? ???? ?? ??? ??????? ???? ?????.

---

??

Web Worker? ?? ? ??? ?? ??? ???, ???? ??? ??? ?????? ??????? ???? ??? ? ??? ????. ??? ??? ??? ????, ??? ??? ???? ????, ??? ??? ???? Web Workers? ?????? ??? ??? ??? ?? ???? ? ????.

? ???? ??? ???? ?? ??? ???? ?????? Web Workers? ??? ??? ? ????. ???? ??? ???? ??????? ? ?? ??? ? ?? ??? ???? ?? ?????!

---

?? ??

• MDN ? ??: ? ???

? ??? JavaScript? ? ?? ?????: ?? ???? ?? ?????. ??? ??? PHP ??? ????? ?? ?? ??? ?????!