如何在使用邮件功能发送电子邮件时为php消息添加换行符？

I have a variable say $message which contains the content to be sent in mail using php mail function. This variable $message will contain text that will also have line breaks. This variable data is being fetched from textarea of another file using ajax.

For instance, the actual text is:
Hello
This is a test message

So while sending mail ($message variable), I see Hello This is a test message, without line break. Is there a way to fix this?

You can use like that:

$message = str_replace ('<br>' , '
', $_POST['textarea']);

You can also use nl2br() function here.

Make sue you are using HTML header in mail() function.