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HomeBackend DevelopmentPHP TutorialDetailed introduction to array_diff_key

Definition and usage The array_diff_key() function is used to compare the key names of two (or more) arrays and return the difference set. This function compares the keys of two (or more) arrays and returns a difference array that includes all the keys in the compared array (array1) but not in any of the other argument arrays (array2 or array3, etc. ) in the key name. Syntax array_diff_key(array1, array2, array3...); Parameter description: array1 is required. The first array to compare with other arrays. array2 is required. The array to compare to the first array. array3,... Optional. Additional array to compare with the first array. Return value: Returns a difference array, which includes all items being compared

1. Definition and usage of the PHP array_diff_key() function

Detailed introduction to array_diff_key

#Introduction: Definition and usage The array_diff_key() function is used to compare the key names of two (or more) arrays and return the difference. This function compares the keys of two (or more) arrays and returns a difference array that includes all keys in the compared array (array1) but not in any of the other argument arrays (array2 or array3, etc. ) in the key name. Syntax array_diff_key(array1,array2,array3...);

2. php-Arrays function-array_diff_key-Use key name comparison to calculate the difference of arrays_PHP tutorial

Introduction: php-Arrays function-array_diff_key-uses key name comparison to calculate the difference of the array. The array_diff_key() function uses key name comparison to calculate the difference set of the array [Function] This function will return an array that contains all the parameters in array1 but not in any other parameter array

3 . How to learn PHP array_diff_key_PHP tutorial

Introduction: How to learn PHP array_diff_key. How to learn PHP array_diff_key Definition and Usage The array_diff_key() function returns an array that includes all the items in the compared array but not in any other parameter array

4. Learn a new PHP function every day (2) array_diff()/array_diff_key()/array_diff_assoc()_PHP tutorial

Introduction: Learn a new PHP function every day Function (2) array_diff()/array_diff_key()/array_diff_assoc(). Learn a new PHP function every day (2) array_diff()/array_diff_key()/array_diff_assoc() array_diff( array array1, array array2 [, array ] ) Description array_diff() returns an array

5. php-Arrays function-array_diff_key-use key name comparison to calculate the difference of arrays

Introduction: php-Arrays function-array_diff_key-use key Name comparison calculates the difference between arrays. The array_diff_key() function uses key name comparison to calculate the difference set of the array [Function] This function will return an array that contains all the parameters in array1 but not in any other parameter array

6 . How to learn PHP array_diff_key

Introduction: How to learn PHP array_diff_key. How to learn PHP array_diff_key Definition and Usage The array_diff_key() function returns an array that includes all items in the compared array but not in any other parameter array

7. Learn a new php function every day (2) array_diff()/array_diff_key()/array_diff_assoc()

Introduction: Learn a new php function every day ( 2) array_diff()/array_diff_key()/array_diff_assoc(). Learn a new PHP function every day (2) array_diff()/array_diff_key()/array_diff_assoc() array_diff( array array1, array array2 [, array ] ) Description array_diff() returns an array

8. array_diff_key: Calculate the difference set of multiple arrays based on the array key

Introduction: array_diff_key($array1,array$array2...) returns a new array with a key in the first array but not in other arrays $arr1 = array('a'='aa' ,'b'='bb','c'='cc','d'='dd');$arr2 = array('a'='aaa','b'='bbb','f' ='fff');$arr = array_diff_key($arr1,$arr2);echo 'pre';print_r

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