Php for array size

PHP array length or size count

This will output 4 as there are four elements inside the array.

You can use sizeof function also to determine the number of values

$value= array(2,5,6,8,9); 
echo "size of array = ".sizeof($value)."
"; // Output = 5 

With COUNT_RECURSIVE (or 1)

We can use optional parameter mode to recursively count the array. ( Total number of keys up to 2 levels )

"apple","quantity"=>2), array("product"=>"Orange","quantity"=>4), array("product"=>"Banana","quantity"=>5), array("product"=>"Mango","quantity"=>7), ); echo count($a); // Output = 4 echo "
"; echo count($a,1); // Output = 12 ?>

echo sizeof($a); // Output = 4 echo "
"; echo sizeof($a,1); // Ouput = 12

Words Count ( Sample projects using sizeof function)

we can use sizeof function to count number of words present in paragraph. Here are the steps involved.

1. Store the paragraph of text in a string variable 
2. Break the variable and create an array by using explode() function with space as delimiter 
3. Count the number of elements present in the array.

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Click here for More on PHP Array functions

• Array functions in PHP
• array : Creating an Array
• Multidimensional array : Creating and displaying
• array_diff Difference of two arrays
• array_count_values counting the frequency of values inside an array
• count : sizeof Array Size or length
• array_push : Adding element to an Array
• array_merge : Adding two arrays
• array_sum : Array Sum of all elements
• array_keys : To get array of keys from an array
• max Getting the maximum or Minimum value of elements in an array
• current Value of present cursor element in an array
• reset Moves the internal pointer to first element
• end Moves the internal pointer to last element
• Array checkbox
• array_map : Using user defined and native function to each element of an array
• current : Returns current element
• reset : Move cursor to first element
• end : Move cursor to last element
• next : Move cursor to next
• prev : Move cursor to previous element
• in_array : IN Array to search for elements inside an array
• is_array : To check the variable is array or not
• array_rand : Random elements of Array
• array_unique : Array Unique values
• Breaking of strings to create array using split command
• Session Array to maintain data in different pages
• unset : Deleting elements of an array by using its key or value
• sort: sorting of PHP array
• usort: Sorting array by using user defined function
• Displaying the elements of an array
• Filtering elements and returning new array based on callback function
• Applying user function to each element of an array
• http_build_query: generate query string using elements to pass through URL

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PHP Array Length Tutorial – How to Get an Array Size

Arrays are a powerful data type in PHP. And knowing how to quickly determine the size of an array is a useful skill.

In this article I’ll give you a quick overview of how arrays work, and then I’ll dive into how to get the size of PHP arrays.

If you already know what arrays are, you can jump straight ahead to the How to get an Array size? section.

What is an Array in PHP?

Before we dive into getting an array size, we need to make sure we understand what an array is. An array in PHP is a variable type that allows you to store more than one piece of data.

For example, if you were storing a simple string, you would use a PHP string type:

$heading = 'PHP Array Length Tutorial';

However, if you wanted to store a few more pieces of separate data, you might consider using a couple of string variables.

$heading = 'PHP Array Length Tutorial'; $subheading = 'How to get an array size'; $author = 'Jonathan Bossenger'

That’s all well and good, but what if you need to store more data, and quickly recall any of those items elsewhere in your code? That’s where an array comes in handy. You can still store the individual pieces of data but using a single variable.

$post_data = array( 'PHP Array Length Tutorial', 'How to get an array size', 'Jonathan Bossenger' );

Each item in that array can be referenced by its numeric key. So instead of needing to recall the single variables, you could reference a single array item by its numeric key.

For even more control, arrays also allow you to define your own array keys, using a string.

$post_data = array( 'heading' => 'PHP Array Length Tutorial', 'subheading' => 'How to get an array size', 'author' => 'Jonathan Bossenger' );

This allows you to also reference the array item by its string key.

You can also define arrays using the new short array notation, which is similar to JavaScript:

$post_data = [ 'heading' => 'PHP Array Length Tutorial', 'subheading' => 'How to get an array size', 'author' => 'Jonathan Bossenger' ];

Arrays can also be nested, forming more complex array variables:

$post_data = [ 'heading' => 'PHP Array Length Tutorial', 'subheading' => 'How to get an array size', 'author' => [ 'name' => 'Jonathan Bossenger', 'twitter' => 'jon_bossenger', ] ]; 

And, you can recall a specific array value using its nested key:

However, if you find yourself regularly doing this, you might want to consider using objects rather than arrays.

Arrays are useful if you need to quickly gather and then use different pieces of related data in a function, or pass that data to another function.

By putting these pieces of data into an array, you have fewer variables defined, and it can make your code easier to read and understand later on. It’s also a lot easier to pass a single array variable to another function than it is to pass multiple strings.

$post_data = [ 'heading' => 'PHP Array Length Tutorial', 'subheading' => 'How to get an array size', 'author' => [ 'name' => 'Jonathan Bossenger', 'twitter' => 'jon_bossenger', ] ]; $filtered_post_data = filter_post_data($post_data)

How to Get the Size of an Array in PHP

Usually when we talk about the size of an array, we’re talking about how many elements exist in that array. There are two common ways to get the size of an array.

The most popular way is to use the PHP count() function. As the function name says, count() will return a count of the elements of an array. But how we use the count() function depends on the array structure.

Let’s look at the two example arrays we defined earlier.

$post_data = array( 'heading' => 'PHP Array Length Tutorial', 'subheading' => 'How to get an array size', 'author' => 'Jonathan Bossenger' ); echo count($post_data);

In this example, count($post_data) will result in 3. This is because there are 3 elements in that array: ‘heading’, ‘subheading’, and ‘author’. But what about our second, nested array example?

$post_data = [ 'heading' => 'PHP Array Length Tutorial', 'subheading' => 'How to get an array size', 'author' => [ 'name' => 'Jonathan Bossenger', 'twitter' => 'jon_bossenger', ] ]; echo count($post_data);

Believe it or not, in this example, count($post_data) will also return 3. This is because by default the count() function only counts the top level array elements.

If you take a look at the function definition, you will see that it accepts two arguments – the array to be counted, and a mode integer. The default value for that mode is the predefined constant COUNT_NORMAL , which tells the function to only count the top level array elements.

If we pass the predefined constant COUNT_RECURSIVE instead, it will run through all levels of nesting, and count those instead.

$post_data = [ 'heading' => 'PHP Array Length Tutorial', 'subheading' => 'How to get an array size', 'author' => [ 'name' => 'Jonathan Bossenger', 'twitter' => 'jon_bossenger', ] ]; echo count($post_data, COUNT_RECURSIVE);

Now, the result of count($post_data, COUNT_RECURSIVE) will be, as expected, 5.

«But wait!», I hear you cry. «you mentioned there was another way?».

Well yes, the other function you can use is sizeof(). However, sizeof() is just an alias of count() , and many folks assume (rightly so) that sizeof() would return the memory usage of an array.

Therefore it’s better to stick with count() , which is a much more suitable name for what you are doing – counting elements in an array.

Thanks for reading! I hope you now have a better understanding of how to find the size of an array in PHP.

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How To Find The Array Length PHP With Examples

The Array Length PHP is the total number of elements present on the given array elements.

In this article, we will talk about Array Length in PHP in a detailed explanation as well as example programs that could be helpful to your future projects. This topic is a continuation of the previous topic, entitled Length Of A String In PHP.

What is array length PHP?

In PHP, array length is usually about the size of an array or shall we see the number of elements were present in that array.

Further, there are two simple ways to find the number of elements present on that given array. But one of the most popular is the count() function . The count() function will return and count the elements present on that given array.

How do you find the length of an array?

To find the array length in PHP we need to used the function count() or a sizeof() this two is a built-in function in PHP which can find the length and count the numbers element of an array and with the use of echo command together with it to find and print the length.

Example program of count() function

Example program of sizeof() function

How many numbers can an array store?

The array can store a number of more or less 100 different values inside. An array is a storage of a list of items with just a single variable, instead of declaring a lot of variables with a value we can declare a lot of values with just only one variable.

In order to access each of the elements that were given in the array we simply use square brackets and a number inside them.

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Is there any restriction on array length in PHP?

There is no restriction nor max on the length of the array. But there is a limit to the amount of memory that can be used in your script which can be changed on the ( memory_limit ) in your PHP script.

What happens if array size is exceeded?

The program will crash once the index of an array size will be exceeded.

Can we resize an array after it has been created?

The array cannot be changed once the array is already been created. The only way to resize the array is to create a new array with a fixed size and then copy all the elements from the existing array to the new array with a fixed size.

Why do we use length in array?

The length of an array can be used to fetch the highest and lowest value which present in the array object.

Does length of array start at 1?

The length of array in PHP is zero based. It means that the array started counting from zero once it was indexed and can count recursive.

Further, the index value of the first array element is 0 and the second index value is 1, and the third index value is 2, and soon.

Do arrays use a lot of memory?

The arrays use a lot of memory for the reason of they require a lot of overhead to store multi dimensional array and the element on each cell array require much memory since each array element have its own different size and type.

Which is faster array or collection?

The array is much faster rather than the collection, but still has drawbacks for too much consumption of memory. While, the collections consume less of the memory, but in terms of performance the execution is very low as compared to the arrays.

More about arrays

Summary

In summary, you have learned about Array Length PHP. This article also discussed what array length is, how do you find the length of an array, how many numbers an array can store, restrictions on array length, what happens if the array size is exceeded, can we resize an array after it has been created, why do we use length in array, does length of array start at 1, do arrays use a lot of memory, and which is faster array or collection.

I hope this lesson has helped you learn a lot. Check out my previous and latest articles for more life-changing tutorials which could help you a lot.

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