How to use WebWorker
This article mainly shows you "how to use WebWorker", the content is easy to understand, clear, hope to help you solve your doubts, the following let the editor lead you to study and learn "how to use WebWorker" this article.
WebWorker is designed to solve the problem that JavaScript does not have multithreading in the browser environment. Under normal circumstances, the browser will block when executing a certain program until it returns to the normal state after the end of the run, and the WebWorker of html5 is to solve this problem and improve the execution efficiency of the program. So the best use scenario for WebWorker is to perform some expensive data processing or computing tasks.
Compatibility of webworker
WebWorker is currently supported by all major browsers except IE. Before creating a webworker, we generally need to check whether the user's browser supports it, as follows:
If (typeof (Worker)! = "undefined") {
/ / support
} else {
/ / browser does not support
}
The creation of webworker
Worker is an object, which is created by the constructor Worker, and the parameter is the path of a js file. The js code in the file will run in the worker thread outside the main thread. It is easy to create the worker as follows:
VarmyWorker=newWorker ('worker.js')
Note: worker runs in another global context (self), which is different from window, so you cannot access window and DOM in woker
There are two types of threads: dedicatedworker and sharedworker;dedicatedworker can only be used in the js context in which it is initialized; sharedworker can be used in multiple js contexts. The commonly used worker is dedicatedworker, and its work can be seen through chrome's debugging tools.
Front-end developers should know that js and UI share a common thread in browsers, and cannot respond to UI; during js computing. If you encounter a task with a large amount of computation, such as manipulating image pixels, the user's behavior will not be responsive. WebWorker is designed to solve the problem that JavaScript does not have multithreading in the browser environment. Browsers that support WebWorker will provide an additional JavaScriptRuntime for WebWorker to use. Its best use scenario is to perform some expensive data processing or computing tasks.
The above is all the contents of the article "how to use WebWorker". Thank you for reading! I believe we all have a certain understanding, hope to share the content to help you, if you want to learn more knowledge, welcome to follow the industry information channel!
