使用PHP获取每两个特定字符之间的字符串

Question

我有这样的字符串：

The time is over. # its mean I'm need to die. Please help me. # Ghost. I am here alone. Sorry. # help yourself.

我想获取每个 # 和点 (.) 之间的文本 所以我用这个：

function get_string_between($string, $start, $end){
    $string = ' ' . $string;
    $ini = strpos($string, $start);
    if ($ini == 0) return '';
    $ini += strlen($start);
    $len = strpos($string, $end, $ini) - $ini;
    return substr($string, $ini, $len);
}

$parsed = trim(get_string_between($url, '#', '.'));
echo $parsed;

问题在于该函数仅返回与我的查询匹配的第一个示例。对于我选择的每个查询，我没有任何想法。

在这个示例字符串中它需要返回这个：

its mean I'm need to die

Ghost

help yourself

编辑@Nick Answer

我真正的字符串是这样的：

Text Text Text # Very good. #:* after this come example. Text Text Text #Very good number 2.

您的代码还返回了#:* 之后的字符串，我只需要这些示例： # Text Text. 或 #Text Text.

在给定的示例中，我需要获取以下文本：

Very good 和 Very good number 2

Answer 1

更新

根据 OP 编辑​​，需要更改正则表达式，以便在 # 之后立即对空格或字母字符使用正向预读，即

/#(?=[ A-Za-z])\s*([^.]*)\./

要使用编辑中的文本：

$string = "Text Text Text # Very good. #:* after this come example. Text Text Text #Very good number 2.";
preg_match_all('/#(?=[ A-Za-z])\s*([^.]*)\./', $string, $matches);
print_r($matches[1]);

输出

Array
(
    [0] => Very good
    [1] => Very good number 2
)

更新demo on rextester

原答案

您可以使用preg_match_all 来获得您想要的结果。此正则表达式在 # 和 . 之间查找一组字符，通过使用非贪婪捕获组和捕获组两侧的 \s* 去除两端的任何空格：

$string = "The time is over. # its mean I'm need to die .
Please help me. # Ghost. I am here alone.
Sorry. # help yourself.";
preg_match_all('/#\s*([^.]*?)\s*\./', $string, $matches);
print_r($matches[1]);

输出：

Array
(
    [0] => its mean I'm need to die
    [1] => Ghost
    [2] => help yourself
)

Demo on rextester

Answer 2

explode、substr 和 strpos 的组合可以做到：

用#分割字符串，然后使用substr和strpos得到#和第一个.之间的字符串。

<?php

$examples = [
    'The time is over. # its mean I\'m need to die.',
'Please help me. # Ghost. I am here alone.',
'Sorry. # help yourself.'];

foreach($examples as $example) {
    $exploded = explode('#', $example);
    $substr = trim(substr($exploded[1], 0, strpos($exploded[1], '.')));
    var_dump($substr);
}

在一个特定字符串的函数中：

$test = parseString('Sorry. # help yourself.');
function parseString($string) {
    $exploded = explode('#', $string);
    $substr = trim(substr($exploded[1], 0, strpos($exploded[1], '.')));

    return $substr;
}

var_dump($test);

对于字符串输入，我们必须执行一个额外的步骤，该步骤之前被\n 打破：

$stringExample = "The time is over. # its mean I'm need to die.
Please help me. # Ghost. I am here alone.
Sorry. # help yourself.";


$test2 = parseString2($stringExample);
function parseString2($string) {
    $result = [];
    $array = explode("\n", $string);

    foreach($array as $a) {
        $exploded = explode('#', $a);
        $substr = trim(substr($exploded[1], 0, strpos($exploded[1], '.')));    
        $result[] = $substr;
    }

    return $result;
}
var_dump($test2);

对于没有换行符的字符串输入，一个小解析器可能如下所示：

$stringExample2 = "The time is over. # its mean I'm need to die. Please help me. # Ghost. I am here alone. Sorry. # help yourself.";


var_dump(parseString3($stringExample2));
function parseString3($stringExample)
{
    $result2 = [];

    $startBlock = false;

    $block = 0;
    foreach (str_split($stringExample) as $char) {
        if ($char === '#') { // Start block
            $startBlock = true;
        } else if ($startBlock && $char === '.') { // End block
            $result2[$block] = trim($result2[$block]); // Remove unnecessary whitespace
            $block++;
            $startBlock = false;
        } else if ($startBlock) { // Character to append to block
            if (!isset($result2[$block])) { // We have to check if the block has been started already and if not, create it as an empty string because otherwise we would get a notice when trying to append our character to it.
                $result2[$block] = '';
            }
            $result2[$block] .= $char;
        }

    }
    return $result2;
}

如果您使用此代码中的任何一个，请确保真正了解正在发生的事情并使用适当的变量名，这些只是 sn-ps 的小示例。

所有示例及其输出都可以在下面的 3v4l 链接中找到

https://3v4l.org/k3TXM