Reprinted PHP array (2)

Reprinted PHP array (2) Original article: taobeibei. iteye. comblog614857 what is an array? When using PHP for development, you need to create many similar variables either early or late. Without many similar variables, you can store data as elements in an array. All elements in the array have their own IDs, so they can be easily accessed. There are three array types: Numeric array with Reprinted PHP array (2)

Http://taobeibei.iteye.com/blog/614857 what is an array?

When using PHP for development, you need to create many similar variables either early or late.

Without many similar variables, you can store data as elements in an array.

All elements in the array have their own IDs, so they can be easily accessed.

There are three types of arrays:

Numeric array

Array with digit ID key

Join array

Each ID key in the array is associated with a value.

Multi-dimensional array

Array containing one or more arrays

Numeric array

Each element stored in the value array has a digital ID key.

You can use different methods to create a numeric array:

Example 1

In this example, the ID key is automatically assigned:

$names = array("Peter","Quagmire","Joe");

Example 2

In this example, we manually allocate the ID key:

$names[0] = "Peter";$names[1] = "Quagmire";$names[2] = "Joe";

You can use these ID keys in the script:

Output of the above code:

Quagmire and Joe are Peter's neighbors

Join array

Join array. each ID key is associated with a value.

It is not the best practice to use a numeric array to store data related to specific named values.

By associating arrays, we can use values as keys and assign values to them.

Example 1

In this example, we use an array to allocate ages to different people:

$ages = array("Peter"=>32, "Quagmire"=>30, "Joe"=>34);

Example 2

This example is the same as example 1, but shows another method to create an array:

$ages['Peter'] = "32";$ages['Quagmire'] = "30";$ages['Joe'] = "34";

You can use the ID key in the script:

Output of the above script:

Peter is 32 years old.

Multi-dimensional array

In a multi-dimensional array, each element in the main array is also an array. Each element in the sub-array can also be an array, and so on.

Example 1

In this example, we create a multidimensional array with an automatically assigned ID key:

$families = array(  "Griffin"=>array  (  "Peter",  "Lois",  "Megan"  ),  "Quagmire"=>array  (  "Glenn"  ),  "Brown"=>array  (  "Cleveland",  "Loretta",  "Junior"  ));

If this array is output, it should be similar to the following:

Array([Griffin] => Array  (  [0] => Peter  [1] => Lois  [2] => Megan  )[Quagmire] => Array  (  [0] => Glenn  )[Brown] => Array  (  [0] => Cleveland  [1] => Loretta  [2] => Junior  ))

Example 2

Let's try to display a single value in the above array:

echo "Is " . $families['Griffin'][2] . " a part of the Griffin family?"; 

Output of the above code:

Is Megan a part of the Griffin family?