如何获得两个字符[字符串]之间的字符串? PHP
问题描述:
$string1 = "This is test [example]";
$string2 = "This is test [example][2]";
$string3 = "This [is] test [example][3]";
如何获得以下结果?如何获得两个字符[字符串]之间的字符串? PHP
For $string1 -> example
For $string2 -> example*2
For $string3 -> is*example*3
答
preg_match_all('/\[([^\]]+)\]/', $str, $matches);
php > preg_match_all('/\[([^\]]+)\]/', 'This [is] test [example][3]', $matches);
php > print_r($matches);
Array
(
[0] => Array
(
[0] => [is]
[1] => [example]
[2] => [3]
)
[1] => Array
(
[0] => is
[1] => example
[2] => 3
)
)
而这里的rregex的解释:
\[ # literal [
(# group start
[^\]]+ # one or more non-] characters
) # group end
\] # literal ]
+0
你能解释一下请正则表达式? 据我所知。 '/'开始正则表达式。 '\'来转义'['。 ''包括一组字符?对 ?你能解释完整的正则表达式吗? – Jashwant
答
对于那些警惕正则表达式,这里有一个解决方案SANS那个疯狂的正则表达式语法。 :-)它曾经真的激怒了我这样的事情是不是原产于PHP的字符串函数,所以我建一个...
// Grabs the text between two identifying substrings in a string. If $Echo, it will output verbose feedback.
function BetweenString($InputString, $StartStr, $EndStr=0, $StartLoc=0, $Echo=0) {
if (!is_string($InputString)) { if ($Echo) { echo "<p>html_tools.php BetweenString() FAILED. \$InputString is not a string.</p>\n"; } return; }
if (($StartLoc = strpos($InputString, $StartStr, $StartLoc)) === false) { if ($Echo) { echo "<p>html_tools.php BetweenString() FAILED. Could not find \$StartStr '{$StartStr}' within \$InputString |{$InputString}| starting from \$StartLoc ({$StartLoc}).</p>\n"; } return; }
$StartLoc += strlen($StartStr);
if (!$EndStr) { $EndStr = $StartStr; }
if (!$EndLoc = strpos($InputString, $EndStr, $StartLoc)) { if ($Echo) { echo "<p>html_tools.php BetweenString() FAILED. Could not find \$EndStr '{$EndStr}' within \$InputString |{$InputString}| starting from \$StartLoc ({$StartLoc}).</p>\n"; } return; }
$BetweenString = substr($InputString, $StartLoc, ($EndLoc-$StartLoc));
if ($Echo) { echo "<p>html_tools.php BetweenString() Returning |'{$BetweenString}'| as found between \$StartLoc ({$StartLoc}) and \$EndLoc ({$EndLoc}).</p>\n"; }
return $BetweenString;
}
当然,这可以浓缩了不少。为了节省别人清除它的努力:
// Grabs the text between two identifying substrings in a string.
function BetweenStr($InputString, $StartStr, $EndStr=0, $StartLoc=0) {
if (($StartLoc = strpos($InputString, $StartStr, $StartLoc)) === false) { return; }
$StartLoc += strlen($StartStr);
if (!$EndStr) { $EndStr = $StartStr; }
if (!$EndLoc = strpos($InputString, $EndStr, $StartLoc)) { return; }
return substr($InputString, $StartLoc, ($EndLoc-$StartLoc));
}
在任何语言中,遍历字符,如果你遇到'['设置的标志,并抓住一切直到']'和取消标志:) – Jashwant