How stop the process of submitting a comment if a fields are empty?

Related Posts:

1. How do I comment out a block of tags in XML?
2. R: Comment out block of code
3. Why do I get comment spam even with Akismet and Captcha?
4. What tools are available for managing/writing to WordPress? [closed]
5. How to rearrange fields in comment_form()
6. setting comments off as default for pages and custom post types?
7. Is it possible to pull comments from facebook into your blog?
8. Filtering the Admin Comments List to Show Only Comments from the Current User?
9. Non-threaded comment replies with link to original comment
10. Approve comment hook?
11. Commenting in user profile page?
12. How to change “You must be logged in to post a comment.”
13. comment_post_ID 0 (cannot remove from dashboard)
14. Disable comments on all posts/pages
15. How do I delete all comments from a specific old blog post?
16. Removing the “Website” Field from Comments and Replies?
17. Stop WordPress redirecting comment-page-1 to the post page?
18. Importing old Disqus comments into WordPress
19. How to add a class to the comment submit button?
20. How to wrap submit button of comment form with div
21. How to enable comments for pending and draft posts?
22. Using WordPress’ WYSIWYG for comments
23. Enable Submit Comment Without Page Reload (Using Ajax)?
24. What for is the table “wp_commentmeta” exactly?
25. Getting Post Comments for post ID using WP_Query() and a Custom Loop?
26. Add option to disable comments on a per posts basis?
27. Resetting comment count
28. When importing – failed to import: Invalid post type feedback
29. How to change the email notification recipient (user) for new comments?
30. Redirect user to a custom url after submitting the comment
31. Paginate result set from $wpdb->get_results()
32. Change Comment Author Display Name
33. Would switching to InnoDB from MyISAM improve performance of comments table?
34. Custom comment type based on thread level
35. How to add internal, revision comments to page updates
36. How to load and show comments with AJAX instead of pagination?
37. Linking to Page Showing Only Comments Without Parent Post
38. Comment Reply javascript
39. How do we remove the H3 tag for the reply-title I.D
40. Comments not appearing at all
41. comments reply script not working
42. How to display comment form error messages in the same page
43. 3 moderators to approve comment
44. How to deal with small scale comment spam on small commercial sites? [closed]
45. What should I do to make generated avatars different for anonymous comments?
46. A plugin where users can comment with Facebook or Twitter or OpenID [closed]
47. Check If comment author is registered
48. Comments screen in backend, how to disable email address of commenter for non admins
49. Add comments from the admin panel?
50. How can I limit the number of comments per registered user per day?
51. One comment per user per post but be able to reply to existing comments
52. How to use a custom comments template
53. Comment visibility
54. What’s the easiest way to close comments on media/attachments?
55. Reverse comment pagination numbers
56. Get comments for more than one post
57. How can I add comments to a page?
58. How to remove comment spam in WordPress
59. Post Comments using WP REST API v2 in WordPress
60. show number of open comments on custom dashboard
61. Show content only if member left a comment
62. Add placeholder attribute to comment form fields
63. Why do I get accidental comments without (the required) email address?
64. How is comment spam received without a comments form?
65. Does a reply to a wordpress comment notify the author of the comment?
66. What are the current recommended best-practices for comments.php?
67. human_time_diff() returns “48 years ago” for all comments
68. How do I set up real anonymous posting in bbpress forums? [closed]
69. Comment Count for each Comment Author
70. Link name in comments to Author page? Comment Author Meta in Comments?
71. How do I turn off wordpress comments ability to capture a users ip address?
72. Showing comments only to same custom user role
73. Parent comment’s author name
74. Success message in comment form
75. get_comments_number of depth-1 (Level 1) (1 post)
76. Show comments from multiple post IDs in comment template
77. Running a function on comment status change
78. How to allow the reply link to remain on the comment form after I have reached my 10 nested comment limit?
79. How can I control the comment counts filtering my CPT replies?
80. Hook to edit an column on comments screen?
81. Allowing more elements in comments via functions.php
82. Set post comments open function
83. Comment Author Name In Reply Form
84. How to auto-approve internal pingbacks?
85. Deep customization of the comment form?
86. Post comment as different user than logged in
87. “Categories” for comments?
88. get recent comments of a particular category
89. Threaded comments – deleting parent comment leads to orphan comments
90. How to hide “Trackback” on paginated comments
91. Allow anonymous comments, but prevent spam [closed]
92. Where to remove from comment’s feed?
93. Hook/Filter before and after comments
94. Using filter to add additional fields to comment_form()
95. How to add editor-style.css styling to wp_editor on front end for comments
96. How to remove commenters ability to add hyperlinks to comments?
97. Comment form validation
98. Why are default comments deprecated?
99. Disable wordpress comments API
100. Is it possible to show custom comment metadata in the admin panel?