PHP arrays and the array types

When writing your code you might need to store a large variable set outside of your database. It will surely be bad practice to save each of the variables separately. Keeping these variables in an array is the best way to go about it, especially if the data items are of the same data type (though arrays can hold varying data types together).

What is an array?

An array is a special variable that stores multiple values at once. If there is a list of items to be stored, it is best to store it in an array. Arrays can be very helpful in writing PHP codes.

Some PHP arrays use cases

• They can be declared empty, and then the output of manipulations is saved in them as the code executes.
• Arrays provide an easy way to loop through a set of items by simply setting its index value as the value of the loop counter.

For example:

$myBestFruits = array('mango','orange','apple');
$counter = 0;
while($counter <= count($myBestFruits)-1)
{
echo $myBestFruits[$counter];
$counter++;
}

The while loop will end if the counter has the value 2, which equals the highest array index 2.

• Also, while working with databases and tables we can fetch the rows of the table as an associative array, which we will discuss later in this shot and use as we please.

In PHP, arrays are declared as shown below:

 $myArrayName = array(/*array values separated by commas*/)

Use the array() with the arguments as the items to be stored. In PHP, arrays are of a different type.

PHP array types

PHP has three basic types of arrays.

1. Indexed arrays: These are the most common and regular array types used in PHP, where the values have numeric indexes by which they can be referenced.

$myBestFruits = array('apple','orange','mango','pineapple');
echo $myBestFruits[0];

The output of this will be apple.

The indexes can also be assigned manually to suit your need.

$myBestFruits[0]="mango";
$myBestFruits[1]="apple";
$myBestFruits[2]="pineapple";
$myBestFruits[3]="orange";

With this, the output of the echo in the code above will now be mango instead of apple.

2. Associative Array: With these arrays, the stored values are given name keys to serve as an index instead of the numeric index. They are mainly used when fetching named columns of a database table.

$myBestFruits = array("firstbest"=>"mango","secondbest"=>"orange");
echo $myBestFruits['firstbest'];

The output will be mango.

An array can be looped using the foreach loop, and also the length can also be determined using the count() parsing the name of the array as an argument. We can perform other operations on an array, like append(), sort(), etc. Now to the third type.

3. Multidimensional arrays: These types of arrays are usually known as arrays of arrays (2d) or arrays of arrays of arrays (3d), and so on. They are simply arrays that contain other arrays.

$myBestFruits = array(
array("mango","green","single-seed"),
array("orange","yellow","multi-seed"),
array("apple","green","less-seed"));
echo $myBestFruits[0][2];

The output of the above code would look like this: single-seed.

Working with arrays can be very tricky, but getting a hold of the concept will ease your coding tasks.