Computes the difference of arrays by using a callback function for data comparison. This is unlike
array_diff()
which uses an internal function for comparing the data.
Parameters
array
The first array.
arrays
Arrays to compare against.
value_compare_func
The callback comparison function.
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed$a,mixed$b):int
Return Values
Returns an array containing all the values of
array
that are not present in any of the other arguments.
Examples
Example #1
array_udiff()
example using stdClass Objects
<?php// Arrays to compare$array1=array(newstdclass,newstdclass,newstdclass,newstdclass,);$array2=array(newstdclass,newstdclass,);// Set some properties for each object$array1[0]->width=11;$array1[0]->height=3;$array1[1]->width=7;$array1[1]->height=1;$array1[2]->width=2;$array1[2]->height=9;$array1[3]->width=5;$array1[3]->height=7;$array2[0]->width=7;$array2[0]->height=5;$array2[1]->width=9;$array2[1]->height=2;functioncompare_by_area($a,$b){$areaA=$a->width*$a->height;$areaB=$b->width*$b->height;if($areaA<$areaB){return-1;}elseif($areaA>$areaB){return1;}else{return0;}}print_r(array_udiff($array1,$array2,'compare_by_area'));?>
Example #2
array_udiff()
example using DateTime Objects
<?phpclassMyCalendar{public$free=array();public$booked=array();publicfunction__construct($week='now'){$start=newDateTime($week);$start->modify('Monday this week midnight');$end=clone$start;$end->modify('Friday this week midnight');$interval=newDateInterval('P1D');foreach(newDatePeriod($start,$interval,$end)as$freeTime){$this->free[]=$freeTime;}}publicfunctionbookAppointment(DateTime$date,$note){$this->booked[]=array('date'=>$date->modify('midnight'),'note'=>$note);}publicfunctioncheckAvailability(){returnarray_udiff($this->free,$this->booked,array($this,'customCompare'));}publicfunctioncustomCompare($free,$booked){if(is_array($free))$a=$free['date'];else$a=$free;if(is_array($booked))$b=$booked['date'];else$b=$booked;if($a==$b){return0;}elseif($a>$b){return1;}else{return-1;}}}// Create a calendar for weekly appointments$myCalendar=newMyCalendar;// Book some appointments for this week$myCalendar->bookAppointment(newDateTime('Monday this week'),"Cleaning GoogleGuy's apartment.");$myCalendar->bookAppointment(newDateTime('Wednesday this week'),"Going on a snowboarding trip.");$myCalendar->bookAppointment(newDateTime('Friday this week'),"Fixing buggy code.");// Check availability of days by comparing $booked dates against $free datesecho"I'm available on the following days this week...\n\n";foreach($myCalendar->checkAvailability()as$free){echo$free->format('l'),"\n";}echo"\n\n";echo"I'm busy on the following days this week...\n\n";foreach($myCalendar->bookedas$booked){echo$booked['date']->format('l'),": ",$booked['note'],"\n";}?>
The above example will output:
I'm available on the following days this week...
Tuesday
Thursday
I'm busy on the following days this week...
Monday: Cleaning GoogleGuy's apartment.
Wednesday: Going on a snowboarding trip.
Friday: Fixing buggy code.
Notes
Note
:
Please note that this function only checks one dimension of a n-dimensional array. Of course you can check deeper dimensions by using
array_udiff($array1[0], $array2[0], "data_compare_func");
.
See Also
array_diff() - Computes the difference of arrays
array_diff_assoc() - Computes the difference of arrays with additional index check
array_diff_uassoc() - Computes the difference of arrays with additional index check which is performed by a user supplied callback function
array_udiff_assoc() - Computes the difference of arrays with additional index check, compares data by a callback function
array_udiff_uassoc() - Computes the difference of arrays with additional index check, compares data and indexes by a callback function
array_intersect() - Computes the intersection of arrays
array_intersect_assoc() - Computes the intersection of arrays with additional index check
array_uintersect() - Computes the intersection of arrays, compares data by a callback function
array_uintersect_assoc() - Computes the intersection of arrays with additional index check, compares data by a callback function
array_uintersect_uassoc() - Computes the intersection of arrays with additional index check, compares data and indexes by separate callback functions
PHP / array_udiff_assoc — DevDocs
array_udiff_assoc
(PHP 5, PHP 7, PHP 8)
array_udiff_assoc
—
Computes the difference of arrays with additional index check, compares data by a callback function
Computes the difference of arrays with additional index check, compares data by a callback function.
Note
:
Please note that this function only checks one dimension of a n-dimensional array. Of course you can check deeper dimensions by using, for example,
array_udiff_assoc($array1[0], $array2[0], "some_comparison_func");
.
Parameters
array
The first array.
arrays
Arrays to compare against.
value_compare_func
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed$a,mixed$b):int
Return Values
array_udiff_assoc()
returns an
array
containing all the values from
array
that are not present in any of the other arguments. Note that the keys are used in the comparison unlike
array_diff()
and
array_udiff()
. The comparison of arrays' data is performed by using an user-supplied callback. In this aspect the behaviour is opposite to the behaviour of
array_diff_assoc()
which uses internal function for comparison.
Computes the difference of arrays with additional index check, compares data and indexes by a callback function.
Note that the keys are used in the comparison unlike
array_diff()
and
array_udiff()
.
Parameters
array
The first array.
arrays
Arrays to compare against.
value_compare_func
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed$a,mixed$b):int
key_compare_func
The comparison of keys (indices) is done also by the callback function
key_compare_func
. This behaviour is unlike what
array_udiff_assoc()
does, since the latter compares the indices by using an internal function.
Return Values
Returns an
array
containing all the values from
array
that are not present in any of the other arguments.
In our example above you see the
"1" => new cr(4)
pair is present in both arrays and thus it is not in the output from the function. Keep in mind that you have to supply 2 callback functions.
Notes
Note
:
Please note that this function only checks one dimension of a n-dimensional array. Of course you can check deeper dimensions by using, for example,
array_udiff_uassoc($array1[0], $array2[0], "data_compare_func",
"key_compare_func");
.
See Also
array_diff() - Computes the difference of arrays
array_diff_assoc() - Computes the difference of arrays with additional index check
array_udiff() - Computes the difference of arrays by using a callback function for data comparison
array_udiff_assoc() - Computes the difference of arrays with additional index check, compares data by a callback function
array_intersect() - Computes the intersection of arrays
array_intersect_assoc() - Computes the intersection of arrays with additional index check
array_uintersect() - Computes the intersection of arrays, compares data by a callback function
array_uintersect_assoc() - Computes the intersection of arrays with additional index check, compares data by a callback function
array_uintersect_uassoc() - Computes the intersection of arrays with additional index check, compares data and indexes by separate callback functions
Computes the intersection of arrays, compares data by a callback function.
Parameters
array
The first array.
arrays
Arrays to compare against.
value_compare_func
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed$a,mixed$b):int
Return Values
Returns an array containing all the values of
array
that are present in all the arguments.
Computes the intersection of arrays with additional index check, compares data by a callback function.
Note that the keys are used in the comparison unlike in
array_uintersect()
. The data is compared by using a callback function.
Parameters
array
The first array.
arrays
Arrays to compare against.
value_compare_func
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed$a,mixed$b):int
Return Values
Returns an array containing all the values of
array
that are present in all the arguments.
Computes the intersection of arrays with additional index check, compares data and indexes by separate callback functions.
Parameters
array1
The first array.
arrays
Further arrays.
value_compare_func
The comparison function must return an integer less than, equal to, or greater than zero if the first argument is considered to be respectively less than, equal to, or greater than the second.
callback(mixed$a,mixed$b):int
key_compare_func
Key comparison callback function.
Return Values
Returns an array containing all the values of
array1
that are present in all the arguments.