1 mei 2016
Javascript Events / keycodes
En eventueel een subtitel om de nieuwsgierigheid aan te wakkeren
Javascript move left
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1 mei 2016
Javascript move left
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Javascript move left setTimeout()
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1 mei 2016
Javascript move left setTimeout()
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Javascript move Mouse event over
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1 mei 2016
Javascript handler
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Event handler
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Event handler
By convention the event is represented by the variable 'event()'.
In some browsers the event must be explicitly passed to the function, so as a precaution it's often
best to include a conditional to test that the event() variable has been passed, and if it hasn't then to
use an alternative method that works on those other browsers:
1 mei 2016
Javascript handler
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Event handler
By convention the event is represented by the variable 'event()'.
In some browsers the event must be explicitly passed to the function, so as a precaution it's often
best to include a conditional to test that the event() variable has been passed, and if it hasn't then to
use an alternative method that works on those other browsers:
Javascript handler
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Event attributes
1 mei 2016
Javascript handler
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Mouse/keyboard
attributes
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Standard Event
Attributes
1 mei 2016
Javascript handler
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Event Handlers as HTML attributes
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Event Handlers as HTML attributes
1 mei 2016
Javascript handler
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Writing an event handling script
element.onclick = doSomething;
if (element.captureEvents)
element.captureEvents(Event.CLICK);
function doSomething(e) {
if (!e) var e = window.event // e refers to the event
}
Javascript handler
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Writing an event handling script
The target/srcElement properties contain a reference to the HTML element the event originally took place on.
Very useful, but when the event is captured or bubbles up the target/srcElement doesn’t change: it’s still the element the event originally took place on. (See the Event properties page for
target/srcElement, see the this page for the this keyword)
1 mei 2016
Javascript handler
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Reading out properties
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Event order
1 mei 2016
Javascript handler
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Keycode example
document.addEventListener("keydown", function(event) {
console.log(event.which);
}
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Keycode example
1 mei 2016
Javascript handler
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Keycode example
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Keycode
example
1 mei 2016
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Keycode example
windows.onload
Javascript handler
