How to use RegEx to get HTML content using Google Apps Script

Question

I am using Google Apps Script. I am trying to fetch the content inside the HTML content fetched from a web page and saved as a string, using RegEx. I want to fetch the data for the below format,

<font color="#FF0101">
        Data which is want to fetch
</font>

Which RegEx should I use to get the data contained within  tags (opening and closing tags). Take care of the color attribute as I only want to fetch the data from those tags which have that color attribute and value as given in the code

Have a look at [RegEx match open tags except XHTML self-contained tags](http://stackoverflow.com/q/1732348/218196) — Felix Kling, Jan 04 '16 at 17:10

Mogsdad · Answer 1 · 2016-01-05T12:17:46.507

Instead of wrestling with using RegEx to parse HTML, you can use Google Apps Script's XmlService to interpret well-formed HTML text.

function myFunction() {
  var xml = '<font color="#FF0101">Data which is want to fetch</font>';
  var doc = XmlService.parse(xml);
  var content = doc.getContent(0).getValue();
  Logger.log( content );  // "Data which is want to fetch"
  var color = doc.getContent(0).asElement().getAttribute('color').getValue();
  Logger.log( color );    // "#FF0101"
}

score 0 · Answer 2 · answered Jan 04 '16 at 17:11

0

You are using JavaScript, so you have NO excuse for trying to parse HTML with regex.

var div = document.createElement('div');
div.innerHTML = "your HTML here";

var match = div.querySelectorAll("font[color='#FF0101']");
// loop through `match` and get stuff
// e.g. match[0].textContent.replace(/^\s+|\s+$/g,'')

answered Jan 04 '16 at 17:11

Niet the Dark Absol

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Niet the Dark Absol, thanks for pointing that out, actually, i wrote that by mistake, I am actually using Google Appscript for that – SKG Jan 04 '16 at 17:17
can you now suggest something ? – SKG Jan 04 '16 at 17:19

Wiktor Stribiżew · Answer 3 · 2016-01-04T21:52:39.853

If JS was fully supported, you could use a DOM-based solution.

var html = "<font color=\"#FF0202\">NOT THIS ONE</font><font color=\"#FF0101\">\n        Data which is want to fetch\n</font>";
var faketag = document.createElement('faketag');
faketag.innerHTML = html;
var arr = [];
[].forEach.call(faketag.getElementsByTagName("font"), function(v,i,a) {
    if (v.hasAttributes() == true) {
      for (var o = 0; o < v.attributes.length; o++) {
        var attrib = v.attributes[o];
        if (attrib.name === "color" && attrib.value === "#FF0101")         {
         arr.push(v.innerText.replace(/^\s+|\s+$/g, ""));
        }
      }
    }
});
document.body.innerHTML = JSON.stringify(arr);

However, acc. to the GAS reference:

However, because Apps Script code runs on Google's servers (not client-side, except for HTML-service pages), browser-based features like DOM manipulation or the Window API are not available.

You may try obtaining the inner text of  tags with a regex:

function myFunction() {
  var doc = DocumentApp.getActiveDocument();
  var paras = doc.getParagraphs();
  var MyRegex = new RegExp('<font\\b[^<]*\\s+color="#FF0101"[^<]*>([\\s\\S]*?)</font>','ig');
  for (i=0; i<paras.length; ++i) {
    while (match = MyRegex.exec(paras[i].getText()))
    {
      Logger.log(match[1]); 
    }
  }
}

Result against NOT THIS ONE Data which is want to fetch:

Regex matches any font tag that have color attribute with the value of #FF0101 inside double quotation marks. Mind that regexps are not reliable when parsing HTML! A better regex for this task is

<font\\b[^<]*\\s+color="#FF0101"[^<]*>([^<]*(?:<(?!/font>)[^<]*)*)</font>

In case your HTML data spans across several paragraphs, use

function myFunction() {
  var doc = DocumentApp.getActiveDocument();
  var text = doc.getBody().getText();
  var MyRegex = new RegExp('<font\\b[^<]*\\s+color="#FF0101"[^<]*>([\\s\\S]*?)</font>','ig');
  while (match = MyRegex.exec(text))
  {
     Logger.log(match[1]); 
  }
}

With this input:

<font color="#FF0202">NOT THIS ONE</font>
<font color="#FF0101">
         Data which is want to fetch
</font>

Result is:

Wait, just came across a note that even plain DOM is not supported. Let me rewrite the answer. — Wiktor Stribiżew, Jan 04 '16 at 21:39
I've just come across a note that even plain DOM is not supported. I have rewritten the answer. — Wiktor Stribiżew, Jan 04 '16 at 21:53
I don't see a reason why it shouldn't work, though you may have to change the expression based on RE2 syntax, as mentioned here: https://support.google.com/a/answer/1371417?hl=en — Sujay Phadke, Jan 05 '16 at 02:18

How to use RegEx to get HTML content using Google Apps Script

3 Answers3