php-Arrays函数-array_flip-交换数组中键和值
array_flip() 函数交换数组中的键和值
【功能】
该函数将返回一个反转后的数组,
即原数组的值变成了新数组的键值,原数组的键值变成了新数组的值
如果数组中有相同的值,则只有最后的一个具有同样值的才会被反转到新数组
【使用范围】
php4、php5.
【使用】
array array_flip( array trans )
trans/必需/进行反转的数组
【示例】
[php]
$array1 = array( "blue" => 6, "red" => 2, "green" => 3, "purple" => 4 );
$array2 = array( "blue" => 6, "red" => 4, "green" => 6, "purple" => 4 );
$array3 = array( "blue" => 6, "red" => 4, "green" => 6, "purple" => '' );
print_r( array_flip( $array1 ) );
print_r( array_flip( $array2 ) );
print_r( array_flip( $array3 ) );
/*
Array
(
[6] => blue
[2] => red
[3] => green
[4] => purple
)
Array
(
[6] => green
[4] => purple
)
Array
(
[6] => green
[4] => red
[] => purple
)
*/
摘自 zuodefeng的笔记

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