magento escape string for javascript

Question

Is there a helper function that will properly escape a string to be rendered as a single quote quoted JavaScript string literal?

I know of jsQuoteEscape but it only handles quotes and does not treat \n & \r etc.

so if my string is 'line1\nlineb' (i.e. two lines with a newline between them)

and I use

var jsvar='<?php echo $this->helper('myextension')->jsQuoteEscape($mystring); ?>';

I will get in the rendered content

    var jsvar='line1
line2';

which is a syntax error.

Thanks, Eyal

Answer 1

Yes

$string = 'Hello
There';                     
var_dump( Mage::helper('core')->jsonEncode($string) );
var_dump( json_encode($string) );

I've never been clear if this encoding a non-object string datatypes as a javascript string is a side-effect of the JSON encoding, or if it's true, according to Hoyle Crockford JSON, so I always like to wrap my strings in an object when passing them around

$o = new stdClass();
$o->param = 'This is my 
Param';         
$json = json_encode($o);            
echo 'var data = ' . $json . ';' . "\n";
echo 'var jsdata = data.param';

This is how you'd handle this with javascript. There's no method that's build specifically for this. If you're interested in seeing the helper methods you do have available from a block, checkout the methods in

app/code/core/Mage/Core/Block/Abstract.php        
app/code/core/Mage/Core/Block/Template.php        

and if you're dealing with a template that's part of a block higher up the chain, get its class and then check its definition

var_dump get_class($this);