I have a jQuery change event for when a user changes a given SELECT element. However the event may also be triggered by a third party script. What I want to do is detect whether the event was triggered programmatically or by the user.
I have tried the accepted solution in this question Check if event is triggered by a human
But note the JSFiddle in this answer is for a click event rather than a change event.
To demonstrate I amended the fiddle and created this one: /
If you try this in latest Firefox or Chrome, you will see that the alert human is being shown even when the event was triggered programmatically.
I have tried event.originalEvent.isTrusted but that doesn't work in all browsers. Can anyone help?
I have a jQuery change event for when a user changes a given SELECT element. However the event may also be triggered by a third party script. What I want to do is detect whether the event was triggered programmatically or by the user.
I have tried the accepted solution in this question Check if event is triggered by a human
But note the JSFiddle in this answer is for a click event rather than a change event.
To demonstrate I amended the fiddle and created this one: http://jsfiddle/Uf8Wv/231/
If you try this in latest Firefox or Chrome, you will see that the alert human is being shown even when the event was triggered programmatically.
I have tried event.originalEvent.isTrusted but that doesn't work in all browsers. Can anyone help?
6 Answers
Reset to default 1I have added mouseenter and mouseleave events. The idea is that it's a human if the click coincided with a mousepointer being over the element. See: http://jsfiddle/Uf8Wv/232/
$("#try").mouseenter(function(event) {
mouseover = true;
});
// ... etc.
I can't think of any other way.
You can find some vague difference between click and emulated click using this code:
$(document).on('change', "#try", function (event) {
//some difference appear in the next line
console.log(event.delegateTarget.activeElement);
//no difference
if (event.originalEvent === undefined) {
alert('not human')
} else {
alert(' human');
}
event.delegateTarget = null;//doesn't help
});
$('#click').click(function (event) {
$("#try").click();
});
Click on the checkbox logs <input id="try" type="checkbox">.
Click on the button logs <button id="click">.
But...
Run $("#try").click(); from console before any clicks logs <body> and after the click result of the last click.
Generally JS can always fake any client event. So isTrusted is never trusted.
You can listen to the click event as well, and modify a variable. The change event seems indeed to be quite similar wheter it's a real click or a script triggered click, but the click on #try event won't be the same. And since click is triggered before change, you have time to set a switch. Like this for example:
var realClick;
$("#try").change(function(event) {
console.log('change')
if (!realClick) {
alert('not human')
} else {
alert(' human');
}
});
$("#try").click(function(event) {
console.log('click')
// originalEvent is one way, but there will be many differences
if (event.originalEvent) {
realClick = true;
} else {
realClick = false;
}
});
// Since this is called from outside, better not put
// any controls here.
$('#click').click(function(event) {
$("#try").click();
});
http://jsfiddle/2xjjmo09/3/
What really worked for me is:
if ((event.originalEvent.isTrusted === true && event.originalEvent.isPrimary === undefined) || event.originalEvent.isPrimary === true) {
//Hey hooman it is you
//Real CLick
}
Tested with jQuery version 3.5
You can easily detect whether the click event on the button is actually triggered by mouse click or not. By doing,
$('#click').click(function(ev) {
if (ev.which !== undefined && ev.button !== undefined) {
$("#try").click();
}
});
Here's the Fiddle
Note: Beware of either ev.which or ev.button could result in 0 on some browser for left-click.
You can check for if event.srcElement (which is source element on which event is triggered) is equal to event.currentTarget something like:
$("#try").change(function(event) {console.log(event,event.target,event.currentTarget,event.srcElement)
if (event.currentTarget=== event.srcElement) {
alert(' human')
} else {
alert(' not human');
}
});
Fiddle: http://jsfiddle/Uf8Wv/234/