There was a change in PHP 4.2.3 that can cause a warning message
to be generated when using stristr(), even though no message was
generated in older versions of PHP.
The following will generate a warning message in 4.0.6 and 4.2.3:
stristr("haystack", "");
OR
$needle = ""; stristr("haystack", $needle);
This will _not_ generate an "Empty Delimiter" warning message in
4.0.6, but _will_ in 4.2.3:
unset($needle); stristr("haystack", $needle);
Here's a URL that documents what was changed:
http://groups.google.ca/groups?selm=cvshholzgra1031224321%40cvsserver
说明
返回 haystack 字符串从 needle 第一次出现的位置开始到结尾的字符串。
参数
-
haystack -
在该字符串中查找。
-
needle -
要搜索的字符串。
Prior to PHP 8.0.0, if
needleis not a string, it is converted to an integer and applied as the ordinal value of a character. This behavior is deprecated as of PHP 7.3.0, and relying on it is highly discouraged. Depending on the intended behavior, theneedleshould either be explicitly cast to string, or an explicit call to chr() should be performed. -
before_needle -
若为
true，strstr() 将返回needle在haystack中的位置之前的部分(不包括 needle)。
参数 needle 和 haystack 将以不区分大小写的方式对待。
返回值
返回匹配的子字符串。如果 needle 未找到，返回 false。
更新日志
| 版本 | 说明 |
|---|---|
| 8.2.0 | 大小写转换不在依赖于使用 setlocale() 设置的区域。只会进行 ASCII 大小写转换。非 ASCII 字节值将通过它们的字节值进行比较。 |
| 8.0.0 |
needle 现在接受空字符串。
|
| 8.0.0 |
不再支持 int 传递给 needle。
|
| 7.3.0 |
弃用 int 传递给 needle。
|
示例
示例 #1 stristr() 示例
<?php
$email = 'USER@EXAMPLE.com';
echo stristr($email, 'e'); // 输出 ER@EXAMPLE.com
echo stristr($email, 'e', true); // 输出 US
?>
示例 #2 测试字符串的存在与否
<?php
$string = 'Hello World!';
if(stristr($string, 'earth') === FALSE) {
echo '"earth" not found in string';
}
// 输出: "earth" not found in string
?>
示例 #3 使用非字符串 needle
<?php
$string = 'APPLE';
echo stristr($string, 97); // 97 = 小写字母 a
// 输出: APPLE
?>注释
注意: 此函数可安全用于二进制对象。
参见
- strstr() - 查找字符串的首次出现
- strrchr() - 查找指定字符在字符串中的最后一次出现
- stripos() - 查找字符串首次出现的位置（不区分大小写）
- strpbrk() - 在字符串中查找一组字符的任何一个字符
- preg_match() - 执行匹配正则表达式
add a note
User Contributed Notes 8 notes
dpatton.at.confluence.org ¶
22 years ago
giz at gbdesign dot net ¶
17 years ago
Just been caught out by stristr trying to converting the needle from an Int to an ASCII value.
Got round this by casting the value to a string.
<?php
if( !stristr( $file, (string) $myCustomer->getCustomerID() ) ) {
// Permission denied
}
?>
Techdeck at Techdeck dot org ¶
21 years ago
An example for the stristr() function:
<?php
$a = "I like php";
if (stristr("$a", "LikE PhP")) {
print ("According to \$a, you like PHP.");
}
?>
It will look in $a for "like php" (NOT case sensetive. though, strstr() is case-sensetive).
For the ones of you who uses linux.. It is similiar to the "grep" command.
Actually.. "grep -i".
notepad at codewalkers dot com ¶
19 years ago
<?php
function stristr_reverse($haystack, $needle) {
$pos = stripos($haystack, $needle) + strlen($needle);
return substr($haystack, 0, $pos);
}
$email = 'USER@EXAMPLE.com';
echo stristr_reverse($email, 'er');
// outputs USER
?>
jukka ¶
10 years ago
I think there is a bug in php 5.3 in stristr with uppercase Ä containing other character
http://pastebin.com/5bP6uztY
if you search only with täry it works, but as soon as the word is tärylä it does not. TÄRYL works fine
tomas dot nesrovnal at yourspirit dot cz ¶
15 years ago
Active item item in menu:
<?php
function aim($page) {
if(stristr($_SERVER['REQUEST_URI'], $page)) {
return ' class="active"';
}
}
?>
usage:
<style type="text/css">
.active {color: red;}
</style>
<?php
print '<a href="http://example.com/page/hello-world/"'. aim('hello-world') .'>HW</a>';
?>
art at awilton dot dotcom ¶
18 years ago
handy little bit of code I wrote to take arguments from the command line and parse them for use in my apps.
<?php
$i = implode(" ",$argv); //implode all the settings sent via clie
$e = explode("-",$i); // no lets explode it using our defined seperator '-'
//now lets parse the array and return the parameter name and its setting
// since the input is being sent by the user via the command line
//we will use stristr since we don't care about case sensitivity and
//will convert them as needed later.
while (list($index,$value) = each($e)){
//lets grap the parameter name first using a double reverse string
// to get the begining of the string in the array then reverse it again
// to set it back. we will also "trim" off the "=" sign
$param = rtrim(strrev(stristr(strrev($value),'=')),"=");
//now lets get what the parameter is set to.
// again "trimming" off the = sign
$setting = ltrim(stristr($value,'='),"=");
// now do something with our results.
// let's just echo them out so we can see that everything is working
echo "Array index is ".$index." and value is ".$value."\r\n";
echo "Parameter is ".$param." and is set to ".$setting."\r\n\r\n";
}
?>
when run from the CLI this script returns the following.
[root@fedora4 ~]# php a.php -val1=one -val2=two -val3=three
Array index is 0 and value is a.php
Parameter is and is set to
Array index is 1 and value is val1=one
Parameter is val1 and is set to one
Array index is 2 and value is val2=two
Parameter is val2 and is set to two
Array index is 3 and value is val3=three
Parameter is val3 and is set to three
[root@fedora4 ~]#
greg at no_ggmac_reply dot com ¶
13 years ago
Beware the example given here:
if stristr($message,'viagra')
or stristr($message,'cialis')
)
{
die();
}
stristr does not search for words, it finds matching substrings. So, for example, the check for 'cialis' will trigger on 'specialist'
