Are event handlers executed synchronously or asynchronously in JavaScript? Here is JS bin which is showing that event handler is executed synchronously.
Code:
$('#toclick').bind('custom', function() {
for (var i=0; i<100000; i++) {}
console.log('Inside click handler');
});
$('#toclick').trigger('custom');
console.log('Outside click handler');
Output:
Inside click handler
Outside click handler
This means if we trigger an event, the code below it won't be executed unless all the event handlers are executed. Am I right ?
Bin with multiple event handlers
That's correct. All event handlers are fired synchronously and in order of binding.
JavaScript IS asynchronous... it will continue to process code, even if a method you called hasn't returned yet... so yes, that is correct. That is the very definition of async: NOT synchronized...
In synchronous operations tasks are performed one at a time and only when one is completed, the following is unblocked. In other words, you need to wait for a task to finish to move to the next one. In asynchronous operations, on the other hand, you can move to another task before the previous one finishes.
Since JavaScript is a single-threaded programming language with a synchronous execution model that processes one operation after another, it can only process one statement at a time.
That's correct. All event handlers are fired synchronously and in order of binding.
Some event handlers are executed synchonously and others asynchronously. See DOM-Level-3-Events
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