stristr

(PHP 4, PHP 5)

stristrstrstr() 函数的忽略大小写版本

说明

string stristr ( string $haystack , mixed $needle [, bool $before_needle = false ] )

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

如果 needle 不是一个字符串,那么它将被转换为整型并被视为字符顺序值。

before_needle

若为 TRUEstrstr() 将返回 needlehaystack 中的位置之前的部分(不包括 needle)。

参数 needlehaystack 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
5.3.0 新增可选的 before_needle 参数。
4.3.0 stristr() 变为二进制安全的。

范例

Example #1 stristr() 范例

<?php
  $email 
'USER@EXAMPLE.com';
  echo 
stristr($email'e'); // 输出 ER@EXAMPLE.com
  
echo stristr($email'e'true); // 自 PHP 5.3.0 起,输出 US
?>

Example #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
?>

Example #3 使用非字符串 needle

<?php
  $string 
'APPLE';
  echo 
stristr($string97); // 97 = 小写字母 a
// 输出: APPLE
?>

注释

Note: 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() - 执行一个正则表达式匹配

add a note add a note

User Contributed Notes 7 notes

up
5
dpatton.at.confluence.org
11 years ago
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
up
2
Techdeck at Techdeck dot org
11 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".
up
0
greg at no_ggmac_reply dot com
3 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'
up
0
giz at gbdesign dot net
6 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
}
?>
up
0
art at awilton dot dotcom
8 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 ~]#
up
0
notepad at codewalkers dot com
8 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

?>
up
-1
tomas dot nesrovnal at yourspirit dot cz
5 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>';
?>
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