Sometimes, we want to fix Uncaught TypeError: Cannot read property ‘value’ of undefined with JavaScript.

In this article, we’ll look at how to fix Uncaught TypeError: Cannot read property ‘value’ of undefined with JavaScript.

How to fix Uncaught TypeError: Cannot read property ‘value’ of undefined with JavaScript?

To fix Uncaught TypeError: Cannot read property ‘value’ of undefined with JavaScript, we should make sure we get the value property of an element.

For instance, we write

const el1 = document.getElementsByName("username")[0];
const el2 = document.getElementById("i1");

to get the first element with name attribute set to username with document.getElementsByName("username")[0].

And we get the element with ID i1 with document.getElementById("i1").

Conclusion

To fix Uncaught TypeError: Cannot read property ‘value’ of undefined with JavaScript, we should make sure we get the value property of an element.