jquery - How to manage " " and ' ' when declare variable in javascript file -

i have search box , user can put search text it. example: book, 'book', "book". , in js file, variable value search box.

var searchtext= "${searchtext}"; <br/> 

this code failed if user put "book" search box.because time,

var searchtext= ""book"". 

if change

var searchtext= "${searchtext}";  var searchtext= '${searchtext}'; 

this code failed if user put 'book' search box. please me, !

you can both replace " or ' single quote '. here's example:

var str= '"book"';  str.replace(/["|']+/g, "'"); 

demo: jsfiddle