19 Jan Field validation and its

IT3215 Introduction to JavaScript

Unit 04 Discussion

DQ1 Validating Form Input Data

Working with and processing bad data generally means that a lot of work will have to be done to clean up the data on the back end. To avoid the processing of bad or incorrect data, we incorporate form validation into our Web pages. There are numerous levels of data validation, from ensuring that input fields are not empty to ensuring the user data entered conforms to a specified format.

Research and describe some tips for someone new to JavaScript to get started. In particular, focus on at least two of the following points while providing sample code (with comments) of each:

How can we set the focus to certain form elements? How do you check for empty input fields?

What is the purpose of using client-side validation versus server-side validation? Explain.

How does a JavaScript function validate numeric and alphabetic inputs in specific fields?

How are regular expressions used to match patterns with strings?

How can a regular expression be used to validate data such as a Social Security number?

Under which circumstances would you use a validation loop?

Why is client-side validation prior to sending data to the server important?

What is the potential problem of overly specific form validation?

How are the + operator and the \n escape sequence used when working with strings to manipulate the DOM to add messages for errors?

Response Guidelines

Comment on the posts of at least two other learners. Offer insights, solutions, examples, or opinions that add depth and value to the conversation.

Learning Components

This activity will help you achieve the following learning components:

Understand how to set focus to certain form elements.

View examples of effective JavaScript comments that describe and explain variables and functions.

Understand how to check for empty input fields.

Understand how a JavaScript function validates numeric and alphabetic inputs in specific fields.

Resources

Discussion Participation Scoring Guide.

Toggle Drawer

DQ2 Challenges With Form Field Validation and Error Messages

Note: The second discussion in each unit of this course is dedicated to community sharing of challenges and solutions you have encountered while completing your weekly assignment. You are encouraged to post and respond early in the week to share experiences that you are having, and to help others with theirs. This is how coders solve tough issues: they rely on one another!

Field validation and its associated error messages are at the heart of creating an effective form. It is important to both understand what information is required in a form (and in which format), and anticipate the user’s experience.

Discuss one or more of the challenges or experiences that you encountered when trying to complete this week’s assignment. How did you try to address it or solve it?

Response Guidelines

Comment on the posts of at least two other learners. Share suggestions to help them address their challenges.

Resources