Javascript - eval() `{}` expression

Question

Why can a string like \"{opacity: 1.0, width: \'132px\'}\" not be evaluated using eval() as is?

eval(\"{opacity: 1.0, width: \'132px\'}         


        

Answer 1

Why can a string like "{opacity: 1.0, width: '132px'}" not be evaluated using eval() as is?

Because {opacity: 1.0, width: '132px'} is invalid javascript as-is. Try putting this statement as-is and you will get a js error. On the other hand v = {opacity: 1.0, width: '132px'} is valid javascript.