(PHP 4, PHP 5, PHP 7)
strtr — Translate characters or replace substrings
+ +$str
+ , string $from
+ , string $to
+ )$str
+ , array $replace_pairs
+ )
+ If given three arguments, this function returns a copy of
+ str where all occurrences of each (single-byte)
+ character in from have been translated to the
+ corresponding character in to, i.e., every
+ occurrence of $from[$n] has been replaced with
+ $to[$n], where $n is a valid
+ offset in both arguments.
+
+ If from and to have
+ different lengths, the extra characters in the longer of the two
+ are ignored. The length of str will be the same as
+ the return value's.
+
+ If given two arguments, the second should be an array in the + form array('from' => 'to', ...). The return value is + a string where all the occurrences of the array keys have been + replaced by the corresponding values. The longest keys will be tried first. + Once a substring has been replaced, its new value will not be searched + again. +
+
+ In this case, the keys and the values may have any length, provided that
+ there is no empty key; additionally, the length of the return value may
+ differ from that of str.
+ However, this function will be the most efficient when all the keys have the
+ same size.
+
+
str+ The string being translated. +
+from
+ The string being translated to to.
+
to
+ The string replacing from.
+
replace_pairs
+ The replace_pairs parameter may be used instead of
+ to and from, in which case it's an
+ array in the form array('from' => 'to', ...).
+
+ Returns the translated string. +
+
+ If replace_pairs contains a key which
+ is an empty string (""),
+ FALSE will be returned. If the str is not a scalar
+ then it is not typecasted into a string, instead a warning is raised and
+ NULL is returned.
+
+
Example #1 strtr() example
+
+<?php
//In this form, strtr() does byte-by-byte translation
//Therefore, we are assuming a single-byte encoding here:
$addr = strtr($addr, "äåö", "aao");
?>
+
++ The next example shows the behavior of strtr() when + called with only two arguments. Note the preference of the replacements + ("h" is not picked because there are longer matches) + and how replaced text was not searched again. +
+Example #2 strtr() example with two arguments
+
+<?php
$trans = array("h" => "-", "hello" => "hi", "hi" => "hello");
echo strtr("hi all, I said hello", $trans);
?>
+
+The above example will output:
+hello all, I said hi +
+ The two modes of behavior are substantially different. With three arguments, + strtr() will replace bytes; with two, it may replace + longer substrings. +
+Example #3 strtr() behavior comparison
+
+<?php
echo strtr("baab", "ab", "01"),"\n";
$trans = array("ab" => "01");
echo strtr("baab", $trans);
?>
+
+The above example will output:
+1001 +ba01 +
+