How to remember php array function

Arrays in PHP are a very useful data type that can hold multiple values ​​and allow you to perform various operations within them. PHP array functions provide convenient methods for operating arrays. This article will introduce some common usage and memory tips of PHP array functions.

1. Array Creation

First, you need to create an array to store the data. It can be useful to use the following functions:

• array(): The easiest way to create an array is to use the array() function.
• []: Create an array using a more concise syntax, which is [].

Both methods can be used to create indexed arrays or associative arrays.

2. Adding and removing elements from arrays

After creating an array, you can use the following functions to add and remove elements:

• array_push (): Add one or more elements to the end of the array.
• array_unshift(): Add one or more elements to the beginning of the array.
• array_pop(): Delete the last element of the array.
• array_shift(): Delete the first element of the array.

It should be noted that array_push() and array_unshift() functions will modify the original array, while array_pop() and array_shift() only return a deleted element and will not modify the original array.

3. Array sorting and flipping

Sorting and flipping arrays are very common operations. The following functions can do it:

• sort (): Sort the array in ascending order.
• rsort(): Sort the array in descending order.
• ksort(): Sort the array by key name.
• krsort(): Reverse sort the array by key name.
• array_reverse(): Reverse the order of elements in the array.

It should be noted that the sort function will change the original array, so it is best to make a backup before sorting the array.

4. Array merging and splitting

You can use the following function to merge multiple arrays into one array:

• array_merge(): A series of arrays combined into a single array.
• array_combine(): Use the values ​​in one array as key names and the values ​​in another array as key values ​​to form a new array.

In addition, you can also use the following function to split an array into multiple arrays:

• array_chunk(): Split an array into multiple smaller arrays.

5. Array search and filtering

Searching and filtering are also common operations. The following are some useful functions:

• in_array(): Search whether the specified element exists in the array.
• array_search(): Search whether the specified value exists in the array and return the key name of the element.
• array_filter(): Use the specified callback function to filter the values ​​in the array.

It should be noted that both the in_array() and array_search() functions can only be used to search for a given value. If more complex search operations are required, the array_filter() function can be used.

The above are some common methods of PHP array functions. You can use these methods to easily operate PHP arrays and complete your project faster. If you use PHP array functions frequently, you may discover some better methods and techniques, and practicing and using them continuously will improve your memory and proficiency.

The above is the detailed content of How to remember php array function. For more information, please follow other related articles on the PHP Chinese website!