Simple Javascript string manipulation

Question

I have a string that will look something like this:

I'm sorry the code "codehere" is not valid

I need to get the value inside the quotes inside the string. So essentially I need to get the codehere and store it in a variable.

After some researching it looks like I could loop through the string and use .charAt(i) to find the quotes and then pull the string out one character at a time in between the quotes.

However I feel there has to be a simpler solution for this out there. Any input would be appreciated. Thanks!

• uadnal: This question may be of some use stackoverflow.com/questions/413071/…

Answer 1

You could use indexOf and lastIndexOf to get the position of the quotes:

var openQuote = myString.indexOf('"'),
 closeQuote = myString.lastIndexOf('"');

Then you can validate they are not the same position, and use substring to retrieve the code:

var code = myString.substring(openQuote, closeQuote + 1);

• pimvdb: Just on a side note - substring (as opposed to substr) accepts start and end so it could be a little bit more straightforward: myString.substring(openQuote, closeQuote + 1). (The +1 is actually also obligatory in substr - now it does not contain the last ").
• Nathaniel Wendt: perfect! I don't know if I was clear enough in what I was asking for judging by the other answers, but this one was what I was looking for. Thanks!
• ShankarSangoli: What if the string is something like this I'm sorry the code "codehere" is not valid, "codethere" is valid
• Justin Ethier: @ShankarSangoli - If that is the case then I agree, you need to use another method such as regular expressions. It depends on the application and where the string is coming from.

Answer 2

Regex:

var a = "I'm sorry the code \"codehere\" is not valid";
var m = a.match(/"[^"]*"/ig);
alert(m[0]);

Answer 3

Try this:

var str = "I'm sorry the code \"cod\"eh\"ere\" is not valid";
alert(str.replace(/^[^"]*"(.*)".*$/g, "1ドル"));

• Bob Fincheimer: What if there is nothing that matches that pattern? then the whole string will be returned?

Answer 4

You could use Javascript's match function. It takes as parameter, a regular expression. Eg:

/\".*\"/

Answer 5

Use regular expressions! You can find a match using a simple regular expressions like /"(.+)"/ with the Javascript RegExp() object. Fore more info see w3schools.com.

• pimvdb: w3schools contains lots of errors, I would not advise to use it.
• Nathaniel Wendt: You probably shouldn't recommend w3schools. A lot of their material is misleading and sometimes downright incorrect. See.. w3fools.com

Answer 6

Try this:

var msg = "I'm sorry the code \"codehere\" is not valid";
var matchedContent = msg.match(/\".*\"/ig);
//matchedContent is an array
alert(matchedContent[0]);

Answer 7

You should use a Regular Expression. This is a text pattern matcher that is built into the javascript language. Regular expressions look like this: /thing to match/flags* for example, /"(.*)"/, which matches everything between a set of quotes.

Beware, regular expressions are limited -- they can't match nested things, so if the value inside quotes contains quotes itself, you'll end up with a big ugly mess.

*: or new RegExp(...), but use the literal syntax; it's better.

Answer 8

You could always use the .split() string function:

var mystring = 'I\'m sorry the code "codehere" is not valid' ;
var tokens = [] ;
var strsplit = mystring.split('\"') ;
for(var i=0;i<strsplit.length;i++) {
 if((i % 2)==0) continue; // Ignore strings outside the quotes
 tokens.push(strsplit[i]) ; // Store strings inside quotes.
}
// Output:
// tokens[0] = 'codehere' ;