Quiz for Validation

Q1: What is the primary purpose of form validation in React?

A. To prevent form submission B. To apply styles C. To check input values for correctness D. To reload the page

Q2: Which HTML attribute can be used for simple required field validation?

A. required B. validate C. check D. verify

Q3: Which event is commonly used to trigger validation logic in React forms?

A. onBlur B. onClick C. onFocus D. onChange

Q4: What does client-side validation ensure?

A. Form reaches the server B. Form is saved to database C. Form data is correct before submission D. Form uses HTTPS

Q5: Which React library is popular for handling complex form validations?

A. React Query B. Formik C. React Router D. Redux

Q6: How do you show a validation message in React?

A. Use an alert() B. Use state to render a message C. Use a prompt() D. Use localStorage

Q7: Which of the following is a built-in HTML5 validation feature?

A. onValidate B. pattern attribute C. validateText() D. requiredClass

Q8: What happens if a required field is left empty and form is submitted?

A. Form submits normally B. An alert box is shown C. Field is highlighted and submission blocked D. Page crashes

Q9: Which method is ideal for validating email format?

A. Use alert() B. Use regex C. Use confirm() D. Use JSON.stringify()

Q10: Which library works well with Formik for schema-based validation?

A. Yup B. Express C. Jest D. Bootstrap

Q11: Where is validation logic usually placed in a React form?

A. Inside return statement B. Outside component C. Inside event handler or custom function D. In CSS

Q12: What does "touched" field state mean in validation?

A. Field has focus B. Field was clicked but not typed C. Field was visited or interacted with D. Field is invalid

Q13: Which error is thrown if validation fails in Formik with Yup?

A. ValidationError B. SyntaxError C. ReferenceError D. FormError

Q14: Which attribute specifies the maximum length of an input field?

A. min B. maxlength C. length D. maxvalue

Q15: Which of the following is a custom validation approach in React?

A. HTML5 validation B. Yup with Formik C. CSS only D. Redux only

Q16: Why is server-side validation still needed?

A. It is faster B. It handles database validation C. It can replace frontend logic D. It creates UI

Q17: How can you disable the submit button until the form is valid?

A. Use CSS only B. Use useRef() C. Track form validity with state and disable based on condition D. Set tabIndex

Q18: What kind of validation is executed before submitting the form to the server?

A. Back-end B. Client-side C. Middleware D. Database

Q19: In Formik, where are error messages stored?

A. in localStorage B. in session C. in the errors object D. in a cookie

Q20: Which hook is useful for managing forms in React?

A. useState B. useRef C. useForm D. useEffect