PHP中的“。=”是什么意思？ [重复]

Question

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• Reference — What does this symbol mean in PHP? 18 answers

I've seen these characters used together in Wordpress PHP, but I'm not sure what they do. An example:

$content .= '' . $title . '';

</div>

Answer 1

That is the short hand version of a concatenation where you say append something to the end of this string itself. It means

$content = $content. $title;