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prevent-listener
The
prevent-listener
snippet prevents the addition of event listeners. You can use
prevent-listener
by wrapping EventTarget.prototype.addEventListener
and not allowing listeners to be added for certain event types.Name | Description | Mandatory |
---|---|---|
type | A pattern that matches the type(s) of events you want to prevent. If the string starts and ends with a slash ( / ), the text in between is treated as a regular expression. | Yes |
handler | A pattern that matches the event handler's declaration. If the string starts and ends with a slash ( / ), the text in between is treated as a regular expression. | No |
selector | The CSS selector that the event target must match. If the event target is not an HTML element, the event handler is added. | No |
The following table lists examples that use the
abort-on-iframe-property-write
snippet:Filter | Result |
---|---|
prevent-listener click | No event listener will be added for click events. |
prevent-listener click console div | No click event listener will be added on div elements whose handler matches console. For example, these listeners won't be added:
window.addEventListener("click", ()=>console.log("click"))
document.body.addEventListener("click", ()=>console.log("click"))
But this listener would be added:
omeDiv.addEventListener("click", ()=>console.log("click")) |
prevent-listener click console | No listener will be added for click events whose handler matches console.
For example, these listeners won't be added:
someElement.addEventListener("click", () => console.log("click"))
But these listeners would be added:
someElement.addEventListener("click", () => alert("click")) |
The following table contains messages you'll find useful during debugging:
Message | When the message occurs | Definition |
---|---|---|
DEBUG [prevent] Wrapped addEventListener | After wrapping | Displayed after addEventListener has been wrapped. |
DEBUG [prevent] was successful
DEBUG [prevent] type: actualType matching providedType
DEBUG [prevent]handler: actualHandler
DEBUG [prevent] matching providedHandler
DEBUG [prevent] on element actualElement matching selector
DEBUG [prevent] was prevented from being added | Each time a listener is prevented from being added | This is a group of logs containing detailed information about the event type and its handler. They're displayed each time we prevent a listener from being added.
If the optional handler or selector parameter was omitted, the corresponding log(s) will be skipped. |
Last modified 9mo ago