While looking through a 3rd party JavaScript API and example code I noticed the following declaration. Basically XML assigned to a string but they seem to split it up on multiple lines using '\', I was unaware this could be done in javascript. Could anyone provide some more details on how this works?

Thanks.

var PrimaryChannel = '<ChannelParams ChannelType="Digital"> \
                                <DigitalChannelParams \
                                    PhysicalChannelIDType="Cable" \
                                    PhysicalChannelID="107" \
                                    DemodMode="QAM256" \
                                    ProgramSelectionMode="PATProgram" \
                                    ProgramID="2"> \
                                </DigitalChannelParams> \
                            </ChannelParams>';

While looking through a 3rd party JavaScript API and example code I noticed the following declaration. Basically XML assigned to a string but they seem to split it up on multiple lines using '\', I was unaware this could be done in javascript. Could anyone provide some more details on how this works?

Thanks.

var PrimaryChannel = '<ChannelParams ChannelType="Digital"> \
                                <DigitalChannelParams \
                                    PhysicalChannelIDType="Cable" \
                                    PhysicalChannelID="107" \
                                    DemodMode="QAM256" \
                                    ProgramSelectionMode="PATProgram" \
                                    ProgramID="2"> \
                                </DigitalChannelParams> \
                            </ChannelParams>';

• javascript
• syntax

• That looks funny because the backslashes are inside the quotes... which makes me believe that it isn't really a JS thing and those slashes are either being preserved in the string, or... they're escaping the newline. – mpen Commented Jul 23, 2010 at 16:42
• @Mark, they ARE escaping the newline – CaffGeek Commented Jul 23, 2010 at 16:43
• 1 @Chad: Yeah.. but I mean, it's not the same thing as closing the quote, and then escaping the newline, is it? In one case you're just telling JS that the line continues so it shouldn't work is magic-semi-colon BS, and in the other case, you're saying what should be included in the string, no? Or maybe I'm confusing languages and how they handle these things... Python for instance lets you butt two strings up next to each other and it'll just join em for you. – mpen Commented Jul 23, 2010 at 16:51
• @Chad: Here's what I mean: pastebin./kW7CvjMc – mpen Commented Jul 23, 2010 at 16:56

3 Answers 3

It is escaping the newline character, but it's not remended. If you minify your js after the fact, it will break horribly.

You are better off doing something like

var myString = 
   ['line1',
    'line2',
    'line3',
    'line4',
    'line5'].join('\n');

or

var mystring = 
    'line1' + 
    'line2' + 
    'line3' + 
    'line4' + 
    'line5';

most browsers support this. it's not standards-pliant however

Yes, you can do that. \ is the line continuation character in JavaScript.

Edit: It's technically an escape character.