How to replace multiple values in php

Question

$srting = "test1 test1 test2 test2 test2 test1 test1 test2";

How can I change test1 values to test2 and test2 values to test1 ?
When I use str_replace and preg_replace all values are changed to the last array value. Example:

$pat = array();
$pat[0] = "/test1/";
$pat[1] = "/test2/";
$rep = array();
$rep[0] = "test2";
$rep[1] = "test1";
$replace = preg_replace($pat,$rep,$srting) ;

Result:

test1 test1 test1 test1 test1 test1 test1 test1 

Answer 1

This should work for you:

<?php

    $string = "test1 test1 test2 test2 test2 test1 test1 test2";

    echo $string . "<br />";
    echo $string = strtr($string, array("test1" => "test2", "test2" => "test1"));

?>

Output:

test1 test1 test2 test2 test2 test1 test1 test2
test2 test2 test1 test1 test1 test2 test2 test1

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