single quotes versus double quotes in js [duplicate]

Answer 1

No, is the right answer most of the time. However if you want to write valid JSON, then you should use double quotes for object literals.

Answer 2

No, except in double quotes you can put single quotes.

e.g. "Don't not do this"

And in single quotes you can put double quotes.

e.g. 'John said "Do this"'

Answer 3

You would mostly use " unless in a position in where you can't escape it. ( It is neater to most developers, Don't ask why )
Also "$myVar" in php will allow the string to have the variables value. ( I know its not javascript, but another example.. In bash,

   echo "What is your name?\nMy name is $(whoami)."

will run the function / command whoami.

<button onclick="dosomething(\"test\")">Test</button> Won't work 
<button onclick="dosomething("test")">Test</button> Won't work 
<section id='"Where-As">
    <button onclick="dosomething('test')">Test</button>
    <!-- will work -->
</section>

P.S: Valid JSON objects should be using double quotes.

Other fun with different quotes:

console.log('\n\n\n\n');  // Will give you \n\n\n\n as a string.
console.log("\n\n\n\n"); // Will give lines.

Answer 4

No difference. Just make sure you close the string with whatever you open it with.

Much more sensible to me than other languages (looking at you, C# and PHP...) where single quoted strings are either character literals, or don't expand escaped characters.

Answer 5

One is slightly wider, so you may have a few extra characters disappear to the right (as opposed to the slimmer version) in your favourite IDE.

Seriously though, I always use ', because if I need to quote a HTML element attribute, I always use " and I can't be bothered escaping like so

var html = "<a href=\"http://www.example.com\">hello</a>"