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Getting the Length of an Array in PHP

To get the array’s length in PHP, you can use the count() and sizeof() functions that return the number of items in the array. Function sizeof() is the alias of the count() function. The count() function returns 0 for a variable initialized by an empty array. In this PHP Array Length example, we obtain the array’s length using the count() function. Click Execute to run the PHP Array Length Example online and see the result.

What is PHP?

PHP is a server-side scripting language that is widely used for web development. PHP supports many protocols and standards, such as HTTP, SMTP, POP3, IMAP, FTP, and XML. PHP can seamlessly integrate with other web development technologies, such as HTML, CSS, JavaScript. One of the key benefits of PHP is its cross-platform compatibility, which means that it can run on multiple operating systems, including macOS, Windows, Linux, and Unix.

What is an array in PHP?

In PHP, an array is a data structure that enables us to store multiple values under a single variable. Each element in an array is associated with a unique index or key, which can be either a string or a number. PHP supports two types of arrays: indexed arrays and associative arrays. Additionally, PHP provides a wide range of built-in functions that can be used to manipulate arrays, including searching, sorting, splitting a string to array, getting the length of an array, converting an string, and converting an array into JSON.

How to count the length of the PHP array?

You can use the count() function to count the length of the specified array. The sizeof() function is an alias for the count() function. The count() function takes two arguments, a list and a length count mode for nested arrays.

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PHP Array Length: How to Find Array Length in PHP [With Examples]

Below is the example we can consider as key and value pair:

Note: we categorize Arrays as “indexed array” and “associative array” based on the key stipulation. The Indexed array has a default index that starts with ‘0’.The associative array includes the user-defined key index. We can use the keys for strings and natural numbers.

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How to create an Array in PHP?

$animals = array(“Bear”, “Leopard”, “Tiger”);

$animals = array(“Leopard”=>”Wild”, “Cow”=>”Domestic”, “Lion”=>”Wild”);

// loop through associative array and get key-value pairs

foreach($animals as $key => $value)

echo “Key=” . $key . “, Value=” . $value;

//two-dimensional array definition declaration

// two-dimensional array iteration declaration

Below is the image as a perfect example for the three-dimensional array:

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PHP | sizeof() Function

The sizeof() function is a built-in function in PHP, and we can use it to count the number of elements present in an array countable object.

Parameter: As per the above syntax example, this function accepts two parameters.

• array: This parameter defines the array which contains elements which we need to count.
• mode: This is an optional parameter, and here we specify the mode of the function. It can take two types of values as per the below:
  • 0: It is default, does not count all elements of multidimensional arrays
  • 1: It Counts the array recursively (It counts all the elements with multidimensional arrays)

  How to Check if a Value Exists in an Array in PHP

  Check if the value exists in an array in PHP

  Step 1 – Use the PHP in_array() function to test if a value exists in an array or not.

  Step 2 – Define the in_array() function

  As per the below code snippet Example:

  $zoo = array(“Leopard”, “Tiger”, “Elephant”, “Zebra”, “Rhino”, “Dear”);

  echo “The elephant was found in the zoo.”;

  echo “The tiger was found in the zoo.”;

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  How to Count all Elements or Values in an Array in PHP

  We can use the PHP count() or sizeof() function to get the particular number of elements or values in an array.

  • The count() and sizeof() function returns 0 for a variable that we can initialize with an empty array.
  • If we do not set the value for a variable, it returns 0.

  Below is the code snippet:

  $days = array(“Sun”, “Mon”, “Tue”, “Wed”, “Thu”, “Fri”, “Sat”);

  How to Print or Echo all the Values of an Array in PHP

  • For printing the array values here we have different ways
  • The easiest method we have foreach loop

  As per the below example, we are repeating the $colors array and print all its elements using the echo or print statement.

  Below is the code snippet:

  $colors = array(“Yellow”, “Purple”, “Red”, “Brown”, “Skyblue”);

  // Loop through colors array

  How to Display Array Structure and Values in PHP

  Use the PHP print_r() or var_dump() Statement

  • For checking the structure and values of an array.
  • You can either use the PHP print_r() or var_dump() statement to see or check the structure and values of an array with an easily readable format on the screen.
  • The var_dump() statement provides better information than print_r().

  Below is the code snippet example we can consider for this:

  $cities = array(“Canada”, “Australia”, “New Jersey”);

  How to Remove the Last Element From an Array in PHP

  Use the PHP array_pop() function

  • For removing the particular value or element from the end of an array.
  • The array_pop() function returns the last value of an array.
  • If the array is empty (without element value in an array list), the returned value will be NULL.

  Below is the code snippet Example to explain how this function runs:

  $sports = array(“Tennis”, “Cricket”, “BasketBall”, “Badminton”);

  

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  Frequently Asked Questions (FAQs)

  Arrays are useful data structures in PHP, which can be used to store multiple values under a single named variable, that too without any need of specifying the type of each individual value. Arrays are one of the fundamental data types in PHP. An array is a collection of elements which can be referenced by an index. You can add new elements, remove existing elements, or change the value stored in any element of an array.

  Finding the length of an array can be quite useful especially in cases where you want to loop through the array and fetch all or some elements inside it. If you want to find the length of an array in PHP, you can use the sizeof function and use the echo command along with it to print the length. The second method is using a function called: count(). This function differs in that it returns the number of elements in an array or object (not just their key values) and also counts the number of array levels in multidimensional arrays.

  PHP has a very rich set of core libraries. In PHP, we have an array of functions we can use to manipulate arrays in different ways without having to create a new function for specific cases. The most common array functions in PHP are: array_merge( $arrays ) — Combines two or more arrays, array_diff( $array1 , $array2 ) — Finds the difference between two arrays, array_map( $callback , $array ) — Creates an array by calling a user-defined function on every array element, array_filter( $array ) — Filters out all elements in an array that do not return true when passed to the callback function.

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  Get the length of an array in PHP.

  This is a beginner’s guide on how to get the length of a PHP array. To count all of the elements in a PHP array, you can either use the count function or the sizeof function.

  Counting the number of elements in a PHP array.

  Do NOT use a loop to count the number of elements in array, as this would be extremely wasteful.

  To count the number of elements in an array, you can use PHP’s native count function like so:

  //An array of names. $names = array( 'John', 'Jason', 'Martina', 'Lisa', 'Tony' ); //Get the number of elements in the array by //using PHP's inbuilt count() function. $numElements = count($names); //Print it out. echo $numElements;

  If you run the code snippet above, you will find that the output of count() is “5”. This is because there is five elements in the $names array.

  Counting elements in a multidimensional array.

  In some cases, you might need to count all of the elements in a multidimensional PHP array. To do this, you will need to use the count function’s second parameter, which is called mode.

  To achieve this, we can simply pass the constant COUNT_RECURSIVE in as the second parameter:

  //A multidimensional array. $arr = array( 1, 2, 10, array( 20, 21, 80 ) ); //Pass COUNT_RECURSIVE in as a second parameter. $numElements = count($arr, COUNT_RECURSIVE); //Print out the result echo $numElements;

  Note that the code above will print out “7” instead of “6”. This is because the array containing 20, 21 and 80 is also considered to be an element (you’d be surprised by how many developers expect the length to be 6).

  The difference between count and sizeof.

  The count function and the sizeof function do the exact same thing. In fact, sizeof is merely an alias of the count function.

  Personally, I would suggest that you stick to using the count function. This is because other programmers may expect the sizeof function to return the size of the array in bytes / memory.

  Note that as of PHP 7.2, the count function will emit an E_WARNING error if you provide it with a variable that isn’t an array or a Countable object.

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