(PHP 4, PHP 5, PHP 7, PHP 8)
substr_replace — Replace text within a portion of a string
$string,$replace,$offset,$length = null
substr_replace() replaces a copy of
string delimited by the
offset and (optionally)
length parameters with the string given in
replace.
stringThe input string.
An array of strings can be provided, in which
case the replacements will occur on each string in turn. In this case,
the replace, offset
and length parameters may be provided either as
scalar values to be applied to each input string in turn, or as
arrays, in which case the corresponding array element will
be used for each input string.
replaceThe replacement string.
offset
If offset is non-negative, the replacing will
begin at the offset'th offset into
string.
If offset is negative, the replacing will
begin at the offset'th character from the
end of string.
length
If given and is positive, it represents the length of the portion of
string which is to be replaced. If it is
negative, it represents the number of characters from the end of
string at which to stop replacing. If it
is not given, then it will default to strlen(
string ); i.e. end the replacing at the
end of string. Of course, if
length is zero then this function will have the
effect of inserting replace into
string at the given
offset offset.
The result string is returned. If string is an
array then array is returned.
| Version | Description |
|---|---|
| 8.0.0 |
length is nullable now.
|
Example #1 Simple substr_replace() examples
<?php
$var = 'ABCDEFGH:/MNRPQR/';
echo "Original: $var<hr />\n";
/* These two examples replace all of $var with 'bob'. */
echo substr_replace($var, 'bob', 0) . "<br />\n";
echo substr_replace($var, 'bob', 0, strlen($var)) . "<br />\n";
/* Insert 'bob' right at the beginning of $var. */
echo substr_replace($var, 'bob', 0, 0) . "<br />\n";
/* These next two replace 'MNRPQR' in $var with 'bob'. */
echo substr_replace($var, 'bob', 10, -1) . "<br />\n";
echo substr_replace($var, 'bob', -7, -1) . "<br />\n";
/* Delete 'MNRPQR' from $var. */
echo substr_replace($var, '', 10, -1) . "<br />\n";
?>
Example #2 Using substr_replace() to replace multiple strings at once
<?php
$input = array('A: XXX', 'B: XXX', 'C: XXX');
// A simple case: replace XXX in each string with YYY.
echo implode('; ', substr_replace($input, 'YYY', 3, 3))."\n";
// A more complicated case where each replacement is different.
$replace = array('AAA', 'BBB', 'CCC');
echo implode('; ', substr_replace($input, $replace, 3, 3))."\n";
// Replace a different number of characters each time.
$length = array(1, 2, 3);
echo implode('; ', substr_replace($input, $replace, 3, $length))."\n";
?>The above example will output:
A: YYY; B: YYY; C: YYY A: AAA; B: BBB; C: CCC A: AAAXX; B: BBBX; C: CCC
Note: This function is binary-safe.