PHP provides various array functions, including: adding and deleting elements: array_push(), array_pop() adding and deleting the first element: array_unshift(), array_shift() merging and difference: array_merge( ), array_diff() Get a part of an array: array_slice() Insert, delete or replace elements: array_splice() Apply a function to array elements: array_map() Filter array elements: array_filter() Group array elements into one value: array_reduce() Check whether the element exists: in_arr
##Common array functions in PHP
1. array_push() and array_pop(): Adding and removing elements
- array_push() Adds one or more elements to the end of the array.
- array_pop() Removes an element from the end of the array and returns that element.
2. array_unshift() and array_shift(): Add and delete the first element
- ##array_unshift()
- in Adds one or more elements to the beginning of the array. array_shift()
- Removes an element from the beginning of the array and returns that element.
- array_merge()
- Combine two Or multiple arrays are combined into a new array, removing duplicates. array_diff()
- Returns the elements in the first array that do not exist in other arrays.
- array_slice()
- Start getting from the specified position of the array Returns a new array with the specified number of elements.
- array_splice()
- Insert, Remove or replace one or more elements.
- array_map()
- to each element in the array Element applies the specified callback function, returning a new array.
- array_filter()
- Filter the array according to the specified callback function, Returns a new array containing elements that satisfy the condition.
- array_reduce()
- Apply array elements to The specified callback function performs the reduction and returns a result.
- in_array()
- Check whether the specified element is in the array , returns a Boolean value.
- array_key_exists()
- Check whether the specified key exists Array, returns a Boolean value.
The above is the detailed content of Common functions and usage of arrays in php. For more information, please follow other related articles on the PHP Chinese website!

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