insert variable as text in javascript

Question

I want to pass a variable as text or somehow to make above function to work:

var title = "Hello World";
chrome.tabs.executeScript(tabId, {code: "var param1='"+title+"'; var param2='value2'; "}, function(){ /*some code*/ });

When I execute above function it not pass title to param1, it must define param1 as title. Because title is dynamic, it can be diffrent, so I really need to know how can pass my title variable.

If I change code like this :

chrome.tabs.executeScript(tabId, {code: "var param1='Hello World!'; var param2='value2'; "}, function(){ /*some code*/ });

than it works perfect

What is the value of tabId? Also, in case you didn't know: chrome.tabs.executeScript will not work in Content scripts. — Rob W
– Rob W, Commented Mar 15, 2012 at 17:58
i am not sure that i understand the question, can you give an example of what output you desire from this? — jbabey
– jbabey, Commented Mar 15, 2012 at 17:59
Above code works good... but param1 value is undefined.. because it not pass. — Jigberto
– Jigberto, Commented Mar 15, 2012 at 18:01
@user It does not pass, so it does not work. Add alert(location.href) in the code, to verify that the code is correctly injected, in the right tab. — Rob W
– Rob W, Commented Mar 15, 2012 at 18:50
it works...I checked! but it pass param1 as undefenited. IF I change code like this than it work perfect as I want: chrome.tabs.executeScript(tabId, {code: "var param1='Hello World'; var param2='value2'; "}, function(){ /*some code*/ }); — Jigberto
– Jigberto, Commented Mar 15, 2012 at 20:27

Rob W · Accepted Answer · 2012-03-15 21:02:04Z

1

Your title string contains quotes, newlines or backslashes. These characters have to be escaped:

var title = 'Your string was here, with a "quote" etc.';

// Escape each special character:
title = title.replace(/[\\"']/g, '\\$&') /* Backslash and quotes */
             .replace(/\n/g, '\\n')      /* Newlines             */
             .replace(/\r/g, '\\r')      /* Carriage returns     */
             .replace(/\t/g, '\\t')      /* Tabs                 */
             .replace(/\b/g, '\\f')      /* Backspace            */
             .replace(/\f/g, '\\b');     /* Form feed            */

chrome.tabs.executeScript(tabId, {code: "var param1='"+title+"'; var param2='value2'; "}, function(){ /*some code*/ })

answered Mar 15, 2012 at 21:02

Rob W

350k87 gold badges811 silver badges683 bronze badges

Sign up to request clarification or add additional context in comments.

9 Comments

Devin Rhode Over a year ago

I actually hard trouble with this, but instead compiled my code with closure compiler, with whitespace only compilation, and, then removed all newlines.

Devin Rhode Over a year ago

This code may throw errors for you if you're trying to clean javascript code to execute. You can to replace newlines, carriage returns, backspace and form feeds with a space character or no char ('')

Rob W Over a year ago

@DevinGRhode "Cleaning JS code to execute"? Can you give an example? The answer will never fail for the circumstances as described by the question. Is your input a valid string? E.g. no unescaped line breaks before a string literal is terminated.

Devin Rhode Over a year ago

I have a live extension update system, so I fetch a js file over the network, store in localStorage, and execute. The code is closure-compiled, which outputs newlines every ~500 chars.

Devin Rhode Over a year ago

If you're googling and have my scenario, where you need to eval javascript, checkout my answer here: stackoverflow.com/a/13775229/565877

|

Collectives™ on Stack Overflow

insert variable as text in javascript

1 Answer 1

9 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

9 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related