<script>
    var html = '<select><option>Mike\'s</option></select>';
</script>

solve the problem within php

str_replace("'", "/'", $str);

solve the problem in js, of course, if the user enters `, it will also report an error. It's better to deal with it in php

var html = `<select><option>Mike's</option></select>`;

escape with backslash:

'Mike\'s'

you can also use double quotes:

"Mike's"

double quotes are not escaped in single quote string , and single quotation marks are not escaped in double quote string .

but note that there is a slight difference between single quotation marks and double quotation marks. For example, variables can be used directly in double quotation marks:

$a='Mike';
"$a's";    //Mike's

there are also more escape characters that can be used in double quotes, such as \ n line breaks, and so on.

the user enters without processing , because it has been processed internally in PHP, where the single quotation marks are characters and will not be paired with the single quotation marks as a language structure.

$a='Mike\'s';    //Mike'sMike\'s

$b="Mike\"s";    //Mike"sMike\"s

$c="something $b";    //$b

if you want to put it in the js code, you can use the addslashes function to deal with it. Please check the documentation for details.