Cache your React event listeners to improve performance.

The Fix

If your function does not depend on your component (no this contexts), you can define it outside of the component. All instances of your component will use the same function reference, since the function is identical in all cases.

The Fix (Advanced)

Author’s Note: I wrote the following examples off the top of my head as a way to repeatedly reference the same function in memory. These examples are meant to make comprehension of references easy. While I would recommend reading this section for the purpose of comprehending references, I would also suggest following it up with the comments section of this article. A few readers have generously contributed better implementations which take into account cache invalidation and React’s built-in memory management.


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