Apex Beginner Progress | ( Lessons)

Lesson: 02 Sets

A Set is a collection type which contains multiple number of unordered unique records. A Set cannot have duplicate records. Like Lists, Sets can be nested.

Set<string> Colors = new Set<string>();

A set with it elements can be declared as the following.

Apex Code

Set<string> Colors = new Set<string>
{'Red', 'Blue', 'Green'};
System.debug('Colors: '+Colors);

Apex Code

Set<string> Colors = new Set<string>
{'Red', 'Blue', 'Green'};
System.debug('The size of the set is : '+Colors.size());

The keyword `add()` can be used to add more element in the set:

Execution Log

Set<string> Colors = new Set<string>
{'Red', 'Blue', 'Green'};
    Colors.add('Orange');
System.debug('The size of the set is : '+Colors.size());

Apex Code

Set<string> Colors = new Set<string>
{'Red', 'Blue', 'Green','Orange'};
    Colors.clear();
System.debug('Colors: '+Colors);

Apex Code

Set<string> Colors = new Set<string>
{'Red', 'Blue', 'Green','Orange'};
    Colors.remove('Green');
System.debug('Colors: '+Colors);

Apex Code

Set<string> Colors = new Set<string>
{'Red', 'Blue', 'Green','Orange'};
    for (String i : Colors) {
      System.debug(i);
    }

Apex Code

Set<string> ColorsLowerCase = new Set<string>
{'Red', 'Blue', 'Black','Pink'};
Set<string> ColorsUpperCase = new Set<String>();
    for (String i : ColorsLowerCase) {
        
        ColorsUpperCase.add(i.toUpperCase());
      
    }
System.debug(ColorsUpperCase);

Exercises

#	Exercise
1	Initializing a New Set
2	Convert a List to a Set

Prev You need to login to have access to the quizzes. Next

Mastered by 163 users.

Apex Beginner

A. Apex Fundamentals (23 lessons)

B. Apex Collections (6 lessons)

C. SOQL (33 lessons)

You need to complete all the quizzes before certification.

Go to top

Lesson: 02 Sets

A set with it elements can be declared as the following.

Apex Code

Execution Log

Video

You can use the `size()` method to find the number of elements of the set:

Apex Code

The keyword `add()` can be used to add more element in the set:

Execution Log

Video

To remove all the elements in the set, use the `clear()` method:

Apex Code

Execution Log

Video

To remove an element, use the `remove()` method and refer to the index number:

Apex Code

Execution Log

Video

Use `for-each` loop to list all the elements of the set:

Apex Code

Execution Log

Video

Converting all the elements of the Set to uppercase using the keyword `toUpperCase()`:

Apex Code

Execution Log

Video

Exercises

Apex Beginner

Login to your account

Lesson: 02 Sets

A set with it elements can be declared as the following.

Apex Code

Apex Beginner