Bootstrap 4 to 5 migration - Mini Project: Build & Apply

Bootstrap 4 to 5 Migration

📖 Scenario: You have a simple webpage styled with Bootstrap 4. You want to update it to use Bootstrap 5, which has some changes in class names and structure.This project will guide you step-by-step to migrate a Bootstrap 4 card component to Bootstrap 5.

🎯 Goal: Update the Bootstrap 4 card component HTML and classes to Bootstrap 5 standards so it renders correctly with Bootstrap 5 styles.

📋 What You'll Learn

Use Bootstrap 5 class names and structure

Replace deprecated classes with new ones

Ensure the card layout and styling remain visually similar

Use semantic HTML5 elements where appropriate

💡 Why This Matters

🌍 Real World

Web developers often need to update existing websites to use the latest Bootstrap version to benefit from improved features and better browser support.

💼 Career

Knowing how to migrate Bootstrap 4 code to Bootstrap 5 is valuable for front-end developers maintaining or upgrading legacy projects.

1

Create the Bootstrap 4 card HTML structure

Write the HTML code for a Bootstrap 4 card with a div having class card, inside it a div with class card-body, and inside that a h5 with class card-title containing the text Card Title. Then add a p with class card-text containing the text This is a Bootstrap 4 card..

Bootsrap

Hint

Use div elements with classes card and card-body. Inside card-body, add a h5 with class card-title and a p with class card-text.

2

Add a Bootstrap 4 button inside the card body

Add a button element inside the card-body with classes btn and btn-primary and the text Click Me.

Bootsrap

  
    Card Title
    This is a Bootstrap 4 card.
    
  

Hint

Inside card-body, add a button with classes btn and btn-primary and text Click Me.

3

Update the card HTML to Bootstrap 5 syntax

Change the button class from btn-primary to btn-primary (same class), but remove any btn-block class if present (Bootstrap 5 removed it). Also, add the class card-header to a new div above card-body with the text Featured.

Bootsrap

  
  
    Card Title
    This is a Bootstrap 4 card.
    Click Me
  

Hint

Add a div with class card-header and text Featured above the card-body div.

4

Replace deprecated Bootstrap 4 classes with Bootstrap 5 equivalents

Remove any form-inline class if present (deprecated in Bootstrap 5). Replace ml-auto with ms-auto for margin start auto. Add text-center class to the card-text paragraph to center the text.

Bootsrap

  Featured
  
    Card Title
    
    This is a Bootstrap 4 card.
    Click Me
  

Hint

Add the class text-center to the p element with class card-text.

Practice

1. Which of the following is a key change when migrating from Bootstrap 4 to Bootstrap 5?

easy

A. Reverting to older grid system from Bootstrap 3

B. Introduction of inline styles for layout

C. Removal of jQuery dependency

D. Use of <center> tag for centering content

Solution

1. Step 1: Understand Bootstrap 5 updates

   Bootstrap 5 removes the jQuery dependency to improve performance and modernize the framework.

2. Step 2: Identify incorrect options

   Options A, B, and C are incorrect because Bootstrap 5 uses CSS for layout (no inline styles), avoids deprecated tags like <center>, and updates the grid system rather than reverting.

3. Final Answer:

   Removal of jQuery dependency -> Option C

4. Quick Check:

   Bootstrap 5 no jQuery = D [OK]

Hint: Remember: Bootstrap 5 dropped jQuery for better speed [OK]

Common Mistakes:

• Thinking Bootstrap 5 uses deprecated HTML tags
• Assuming jQuery is still required
• Confusing grid system changes with older versions

2. Which is the correct way to update a Bootstrap 4 button class btn btn-primary to Bootstrap 5?

easy

A. btn-primary btn

B. btn btn-primary-5

C. button-primary

D. btn btn-primary remains the same in Bootstrap 5

Solution

1. Step 1: Check Bootstrap 5 button class changes

   Bootstrap 5 keeps button classes like btn btn-primary unchanged for backward compatibility.

2. Step 2: Verify other options

   Options B, C, and D are invalid class names and will not style the button correctly.

3. Final Answer:

   btn btn-primary remains the same in Bootstrap 5 -> Option D

4. Quick Check:

   Button classes stable = A [OK]

Hint: Button classes mostly unchanged from v4 to v5 [OK]

Common Mistakes:

• Adding extra numbers to class names
• Changing class order incorrectly
• Using non-existent class names

3. What will be the visual result of this Bootstrap 5 code snippet?

<div class="d-flex justify-content-center">
  <button class="btn btn-success">Click Me</button>
</div>

medium

A. A green button centered horizontally inside a flexible container

B. A green button aligned to the left inside a block container

C. A red button centered vertically

D. A button with no styling or alignment

Solution

1. Step 1: Analyze container classes

   The d-flex class makes the container a flexbox, and justify-content-center centers content horizontally.

2. Step 2: Analyze button classes

   The btn btn-success classes style the button green with Bootstrap's success theme.

3. Final Answer:

   A green button centered horizontally inside a flexible container -> Option A

4. Quick Check:

   Flex center + btn-success = C [OK]

Hint: d-flex + justify-content-center centers horizontally [OK]

Common Mistakes:

• Confusing justify-content-center with vertical centering
• Mixing button color classes
• Ignoring flex container effects

4. You have this Bootstrap 4 modal trigger button:

<button type="button" class="btn btn-primary" data-toggle="modal" data-target="#myModal">Open</button>

What is the correct way to update it for Bootstrap 5?

medium

A. data-bs-toggle="modal" data-bs-target="#myModal"

B. data-toggle="modal" data-target="#myModal" (no change needed)

C. data-modal-toggle="myModal"

D. data-toggle-modal="#myModal"

Solution

1. Step 1: Identify Bootstrap 5 data attribute changes

   Bootstrap 5 prefixes data attributes with data-bs- to avoid conflicts, so data-toggle becomes data-bs-toggle.

2. Step 2: Verify correct attribute names

   data-bs-toggle="modal" data-bs-target="#myModal" uses correct new attributes. Options A, C, and D use old or invalid attributes.

3. Final Answer:

   data-bs-toggle="modal" data-bs-target="#myModal" -> Option A

4. Quick Check:

   Bootstrap 5 data attributes start with data-bs- [OK]

Hint: Add 'bs' prefix to data attributes in Bootstrap 5 [OK]

Common Mistakes:

• Leaving old data attributes unchanged
• Using incorrect attribute names
• Removing necessary attributes

5. You want to migrate a Bootstrap 4 grid layout using col-md-6 and offset-md-3 to Bootstrap 5. Which is the correct updated class for offset in Bootstrap 5?

medium

A. ms-md-3

B. offset-md-3 remains the same

C. offset-md-start-3

D. offset-md-3 replaced by offset-md-3-start

Solution

1. Step 1: Check offset class changes in Bootstrap 5

   Bootstrap 5 keeps offset classes like offset-md-3 unchanged for grid layout offsets.

2. Step 2: Analyze other options

   Options B, C, and D are invalid or do not exist in Bootstrap 5's grid system.

3. Final Answer:

   offset-md-3 remains the same -> Option B

4. Quick Check:

   Offset classes stable in Bootstrap 5 = A [OK]

Hint: Offset classes keep same names in Bootstrap 5 [OK]

Common Mistakes:

• Changing offset class names unnecessarily
• Confusing margin utilities with offset classes
• Using invalid class syntax