Add value to php array. Adding an element to the beginning of the array. Adding and Removing Array Elements

Adding elements to an array

If the array exists, additional elements can be added to it. This is done directly using the assignment operator (equal sign) in the same way as assigning a value to a string or number. In this case, you don’t have to specify the key of the added element, but in any case, square brackets are required when accessing the array. Adding two new elements to $List, we'll write:

$List = "pears";
$List = "tomatoes";

If the key is not specified, each element will be added to the existing array and indexed by the next ordinal number. If we add new elements to the array from the previous section, whose elements had indexes 1, 2 and 3, then pears will have index 4, and tomatoes will have index 5. When you explicitly specify an index, and the value with it is already exists, the existing value at that location will be lost and replaced with a new one:

$List = "pears";
$List = "tomatoes";

Now the value of the element with index 4 is “tomatoes”, and the element “oranges” is no longer there. I would advise not to specify a key when adding elements to an array, unless you specifically want to overwrite any existing data. However, if strings are used as indexes, the keys must be specified so as not to lose values.

We will try to add new elements to the array by rewriting the soups.php script. First by printing source elements array, and then the original ones along with the added ones, we can easily see the changes that have occurred. Just as you can find out the length of a string (the number of characters it contains) using the strlen() function, it is also easy to determine the number of elements in an array using the count() function:

$HowMany = count($Array);

1. Open soups.php file in text editor.
2. After initializing the array using the array() function, add the following entry:
$HowMany = count($Soups);
print("The array contains $HowMany elements.

\n");

The count() function will determine how many elements are in the $Soups array. By assigning this value to a variable, it can be printed.

3. Add three additional elements to the array.
$Soups["Thursday"] = "Chicken Noodle";
$Soups["Friday"] = "Tomato";
$Soups["Saturday"] = "Cream of Broccoli";
4. Count the elements in the array and print this value.
$HowManyNow = count($Soups);
print("The array now contains $HowManyNow elements.

\n");

5. Save the script (Listing 7.2), upload it to the server and test it in the browser (Fig.).

Listing 7.2 You can directly add one element at a time to an array by assigning a value to each element using the appropriate operator. The count() function can be used to find out how many elements are in an array.

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