Sometimes, we want to add validation using Yup to check string or number length with JavaScript.
In this article, we’ll look at how to add validation using Yup to check string or number length with JavaScript.
How to add validation using Yup to check string or number length with JavaScript?
To add validation using Yup to check string or number length with JavaScript, we call the test method.
For instance, we write
yup
.string()
.test("len", "Must be exactly 5 characters", (val) => val.length === 5);
to call test with 'len', an validation error string, and a callback to do the validation.
We check that the val has length 5 with (val) => val.length === 5.
Conclusion
To add validation using Yup to check string or number length with JavaScript, we call the test method.
