This article mainly introduces the method of assigning values in an array to a set of variables in PHP. It has a certain reference value. Now I share it with you. Friends in need can refer to it
( PHP 4, PHP 5, PHP 7)
list — Assign the values in the array to a set of variables
array list ( mixed $var1
[, mixed $...
] )
Like array(), this is not a real function, but a language construct. list() You can assign values to a set of variables in a single operation.
Note:
list() can only be used with numerically indexed arrays, and assumes numbers The index starts from 0.
Warning
In PHP 5, list() starts with the rightmost parameter Assignment; In PHP 7, list() assigns values starting from the leftmost parameter.
If you use simple variables, don't worry about this. But if you use an indexed array, usually you expect the result to be left to right as written in list(), but in PHP 5 it is not, It is assigned in reverse order.
The left side of the equal sign is the list() function, and the right side is the index array (the subscripts are consecutive, starting with 0);
There are several elements in the array, then list() has several parameters (the parameters must be variables and not values, and the variables are custom variables), which are one by one with the value of the array. Correspondence;
In the parameters of the list() function, empty items also represent elements
<?php list(,,$c) = ['aa','bb','cc']; echo $c;//ccecho '<br>'; list($a1,$b1,$c1) = ['aa1','bb1','cc1']; echo $a1.$b1.$c1;//aa1bb1cc1 echo '<br>'; list($a2,,$c2) = ['aa2','bb2','cc2']; echo $a2.$c2;//aa2cc2 echo '<br>'; list($a3,$b3,$c3) = [1=>'aa3',2=>'bb3',0=>'cc3']; echo $a3.$b3.$c3;//cc3aa3bb3 echo '<br>'; list($a4,$b4,$c4) = [1=>'aa4',2=>'bb4',3=>'cc4']; echo $a4.$b4.$c4;//aa4bb4 Notice: Undefined offset: 0 in D:\phpStudy\WWW\demo\function.php on line 14 echo '<br>'; list($a5,$b5,$c5) = [1=>'aa5',2=>'bb5','a'=>'cc5']; echo $a5.$b5.$c5;//aa5bb5 Notice: Undefined offset: 0 in D:\phpStudy\WWW\demo\function.php on line 18 echo '<br>';
The above is the entire content of this article. I hope it will be helpful to everyone’s study. For more related content, please pay attention to the PHP Chinese website!
# Related recommendation:
PHP Methods based on the duration of PHP
The above is the detailed content of How to assign values in an array to a set of variables in PHP. For more information, please follow other related articles on the PHP Chinese website!