How to delete the seemingly blank space in the string?

$str ='                            Controllable Eu valence for photoluminescence tuning in apatite-typed';在编码为GBK的情况下是'聽 聽 聽 聽 聽 聽 聽 聽 聽 聽 聽 聽 聽 聽Controllable Eu valence for photoluminescence tuning in apatite-typed'；在utf-8下是'                            Controllable Eu valence for photoluminescence tuning in apatite-typed';

如何去除空格？

Reply content:

$str ='                            Controllable Eu valence for photoluminescence tuning in apatite-typed';在编码为GBK的情况下是'聽 聽 聽 聽 聽 聽 聽 聽 聽 聽 聽 聽 聽 聽Controllable Eu valence for photoluminescence tuning in apatite-typed'；在utf-8下是'                            Controllable Eu valence for photoluminescence tuning in apatite-typed';

如何去除空格？

Use$str = preg_replace('/^[\pZ\pC]+|[\pZ\pC]+$/u','',$str);

http://php.net/manual/zh/regexp.reference.unicode.php

Used to match common character types when UTF-8 mode is selected

PC: All Unicode "other"
PZ: All Unicode "separator", all spaces and invisible characters

PHP merges multiple contiguous spaces:
$output = preg_replace('/\s+/', ' ', $input);
\sMatches any whitespace character, including spaces, tabs, page breaks, and so on, equivalent to [ \f\n\r\t\v] .
http://php.net/manual/zh/reference.pcre.pattern.syntax.php

$STR = $str. Replace (/s/g, ");

UrlEncode to see what the character is, (is it a space or something else)

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