Basic php Tutorial-array operations

If you have a large array and all you need to do is find an existing given value, you can use in_array () to return true or false, the following code outputs "Notfoundinthisarray" because you will find an existing "Alber" in $ namesArray"

If you have a large array and all you need to do is find an existing given value, you can use in_array () to return true or false, the following code outputs "Not found in this array" because you will find an existing "Alber" in $ namesArray ".

If you have a large array and all you need to do is find an existing given value, you can use in_array () to return true or false, the following code outputs "Not found in this array" because you will find an existing "Alber" in $ namesArray ".

2. $ NamesArray = array ("Joe", "Jane", "Bob", "Mary", "Paul", "Eddie", "John ");
3. $ LookingFor = "Albert ";
4. If (in_array ($ lookingFor, $ namesArray )){
5. Echo "You 've got it! ";
6. } Else {
7. Echo "Not found in this array! ";
8. }
9. ?>

If You change the value of $ lookingFor to "Mary", You will receive the message "You 've got it !", Because "Mary" is part of $ namesArray.

To count array elements, you can use the count () function:

2. $ NamesArray = array ("Joe", "Jane", "Bob", "Mary", "Paul", "Eddie", "John ");
3. $ Count = count ($ namesArray );
4. ?>

The $ count value is 7.

You can add elements to any array. whether at the beginning or end of an existing array, you can also use a function to create a new array containing two or more array elements, when merging, each array is arranged in the required order. if your array already has an internal order, you need to re-sort the new merged array.

Let's start by adding elements to the end of an existing array and use the array_push () function ():

2. /* Create the original array */
3. $ FruitArray = array ("apple", "orange", "banana", "kiwi", "pear ");
4. /* Add to the original array */
5. Array_push ($ fruitArray, "grape", "pineapple", "tomato ");
6. /* List each element by its key value */
7. While (list ($ key, $ value) = each ($ fruitArray )){
8. Echo "$ key: $ value
   ";
9. }
10. ?>

This will show:

0: apple1: orange2: banana3: kiwi4: pear5: grape6: pineapple7: tomato

When you need to add elements to the beginning of an array, the code is very similar. The difference is only the function name: array_unshift () rather than array_push ():

2. /* Create the original array */
3. $ FruitArray = array ("apple", "orange", "banana", "kiwi", "pear ");
4. /* Add to the original array */
5. Array_unshift ($ fruitArray, "grape", "pineapple", "tomato ");
6. /* List each element by its key value */
7. While (list ($ key, $ value) = each ($ fruitArray )){
8. Echo "$ key: $ value
   ";
9. }
10. ?>
11. // This will display:
12. // 0: grape
13. // 1: pineapple
14. // 2: tomato
15. // 3: apple
16. // 4: orange
17. // 5: banana
18. // 6: kiwi
19. // 7: pear

The array_merge () function combines two or more arrays:

2. /* Create the original array */
3. $ FruitArray = array ("apple", "orange", "banana", "kiwi", "pear ");
5. $ VegArray = array ("carrot", "green beans", "asparagus", "artichoke", "corn ");
6. /* Merge into an array */
7. $ GoodfoodArray = array_merge ($ fruitArray, $ vegArray );
8. /* List each element by its key value */
9. While (list ($ key, $ value) = each ($ goodfoodArray )){
10. Echo "$ key: $ value
    ";
11. }
12. ?>
13. // This will display:
14. // 0: apple
15. // 1: orange
16. // 2: banana
17. // 3: kiwi
18. // 4: pear
19. // 5: carrot
20. // 6: green beans
21. // 7: asparagus
22. // 8: artichoke
23. // 9: corn

Now you have added and merged elements to the array. now you can use the array_pop () function to delete an element from the end of the array. if you use the array_shift () function (), delete an element from the beginning of the array. In fact, when you delete an element from the array, this element is still available for you-when you pop or shift an element from an existing array.

Use the array_pop () function to delete a value from the end of the array:

2. /* Create an array */
3. $ FruitArray = array ("apple", "orange", "banana", "kiwi", "pear ");
4. /* A value is displayed at the end */
5. $ Popped = array_pop ($ fruitArray );
6. /* List the content of the new array and the pop-up values */
7. While (list ($ key, $ value) = each ($ fruitArray )){
8. Echo "$ key: $ value
   ";
9. }
10. Echo"
    And finally, in $ popped: $ popped ";
11. ?>
12. // This will display:
13. // 0: apple
14. // 1: orange
15. // 2: banana
16. // 3: kiwi

Next, delete a value from the end of the array:

2. /* Create an array */
3. $ FruitArray = array ("apple", "orange", "banana", "kiwi", "pear ");
4. /* Remove a value from the array header */
5. $ Shifted = array_shift ($ fruitArray );
6. /* List the content of the new array and the removed value */
7. While (list ($ key, $ value) = each ($ fruitArray )){
8. Echo "$ key: $ value
   ";
9. }
10. Echo"
    And finally, in $ shifted: $ shifted ";
11. ?>
12. // This will display:
13. // 0: orange
14. // 1: banana
15. // 2: kiwi
16. // 3: pear
17. // And finally, in $ shifted: apple

There are many functions that can help you sort array elements, but I will demonstrate basic sorting to help you understand the process:

2. /* Create the original array */
3. $ FruitArray = array ("apple", "orange", "banana", "kiwi", "pear ");
4. /* Sort */
5. Sort ($ fruitArray );
6. /* Reset it to display the array correctly from start to end */
7. /* List each element by its key value */
8. While (list ($ key, $ value) = each ($ fruitArray )){
9. Echo "$ key: $ value
   ";
10. }
11. ?>
12. // This will display:
13. // 0: apple
14. // 1: banana
15. // 2: kiwi
16. // 3: orange
17. // 4: pear