Question

I’m connecting to a PHP webservice that returns URLs of images in JSON (using the PHP json_encode function).

I’m working within a mootools 1.2.5 system, which also needs to work on mobile phones.

The format of the image node returned in the data is like this:

"thumb": "<img src=\"http://photos.imgserv.com/201107222000000.jpg\"  />"

For some reason iphone and android see a NULL value when I pass the response.JSON to them. I can pass the response.text object to them with no problem, but then the JSON.decode fails since the double quotes are not escaped properly. If I manually add double back slashes on the image tags like this:

"thumb": "<img src=\\"http://photos.imgserv.com/201107222000000.jpg\\"  />"

it all works as designed. However, I’m having a hell of a time getting the right regexp to replace the \" in the original response.text with \\".

Is there a “right” way to handle the response.JSON to mobile phones, and alternately how can I properly write the string.replace() regex to handle these escape chars?

Thanks!

EDIT TO ADD:

Here’s two jsfiddles with the single and double backslash to show the issue:

Single backslash (doesn’t decode/parse properly) — http://jsfiddle.net/Qde6F/
Double backslash (does decode/parse properly) — http://jsfiddle.net/Qde6F/1/

Answer 1

did you try something like this…

var src = "\"thumb\": \"<img src=\\\"http://photos.imgserv.com/201107222000000.jpg\\\"  />\"";
alert(src);
var dest = src.replace("\\\"","\\\\\"");
alert(dest);

ie, the replace expression is replace("\\\"","\\\\\""), which replace \" with \\"

Ok, this worked for me in the jsfiddler

var text = '[{"thumb": "<img src=\"http://photos.imgserv.com/201107222000000.jpg\"  />" }]';

console.dir(text);
var dest = text.replace(/(src=)(\")([^"]+)(\")/g,"$1\\\"$3\\\"");
console.dir(dest);

console.dir(JSON.decode(dest));​

Basically the regex rewrites the src="url" to be src=\"url\".