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Handle form validation when a value changes in Svelte

Andrew Smith
InstructorAndrew Smith
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Published 4 years ago
Updated 2 years ago

You will look at validating a form field when a value has changed and focus has been moved away with the handleChange function from the svelte-forms-lib.

Andrew Smith: [0:01] Let's add handleChange to our destructured properties from createForm. Let's add the handleChange function to our username input field with an on directive followed by the changeEvent = handleChange.

[0:13] We can repeat this process for password field, and then test it out in the browser. If we enter a space in our username field and tab to the next field, we now see an error message.

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