Using JavaScript, create a regular expression with variables that can be used to identify and match a specific section of

Question

Using JavaScript, create a regular expression with variables that can be used to identify and match a specific section of

Struggling to apply a regex (with 1 variable) to compare against a HTML code page stored as text.

The HTML code is separated into an array, with each element representing a snippet like the one below. Each element showcases details of fictional Houses (name, square footage, etc). My objective is to identify and match just one of these houses by extracting the text between the first TD tags. Specifically, I am interested in the VALUE (digits) inside the last INPUT tag of the form.

<TR BGCOLOR=#D4C0A1>
 <TD WIDTH=40%><NOBR>Luminous&#160;Arc&#160;2</NOBR></TD>
 <TD WIDTH=10%><NOBR>154&#160;sqm</NOBR></TD>
 <TD WIDTH=10%><NOBR>6460&#160;gold</NOBR></TD>
 <TD WIDTH=40%><NOBR>rented</NOBR></TD>
 <TD><TABLE BORDER=0 CELLSPACING=0 CELLPADDING=0>
 <FORM ACTION= METHOD=post><TR><TD>
  <INPUT TYPE=hidden NAME=world VALUE=Olympa>
  <INPUT TYPE=hidden NAME=town VALUE="Yalahar">
  <INPUT TYPE=hidden NAME=state VALUE=>
  <INPUT TYPE=hidden NAME=type VALUE=houses>
  <INPUT TYPE=hidden NAME=order VALUE=>
  <INPUT TYPE=hidden NAME=houseid VALUE=37010>
  <INPUT TYPE=image NAME="View" ALT="View" SRC="" BORDER=0 WIDTH=120 HEIGHT=18>
</TD></TR></FORM></TABLE></TD></TR>

I formulated the following regular expression:

var regex = new RegExp(house + "[\\s\\S]+name=houseid value=([0-9]+)>", "i");

where house refers to the house name (e.g., Luminous Arc 2) and the essential piece I seek is the houseid 37010.

I assumed this Regex would provide me with the needed result, yet houses[i].match(regex) consistently returns null. No matches are found in the string.

I've experimented with various methods, even trying to convert the HTML string into a DOM Object for parsing TR tags (unsuccessful). Progress seems within reach, but I'm currently at a standstill.

If anyone can discern why my regex isn't functioning correctly, it would be greatly appreciated.

Kenneth

javascript regex

Answer 1

Answer №1

To easily access the DOM in your HTML, you can add the string within a hidden div and retrieve it as needed.

Here is an example:

<div id="stringContainer"></div>

var searchstring = "Luminous&#160;Arc&#160;2";
searchstring = searchstring.replace(/&#160;/g, '&nbsp;') // Convert &#160; to &nbsp;

var c = document.getElementById("stringContainer");
c.innerHTML = '<table>'+houses+'</table>';
var h = c.getElementsByTagName('tr');

for(var i = 0, l = h.length; i < l; i++){ 
    var name = h[i].firstChild.nextSibling.getElementsByTagName('nobr')[0]; 
    if(name && name.innerHTML == searchstring){ 
        console.log(h[i].getElementsByTagName('input')[5].value) 
    }
}

Here's a working example

If we assume that the variable houses contains the following data:

var houses = '...'; // Data goes here

Answer 2

To easily access the DOM in your HTML, you can add the string within a hidden div and retrieve it as needed.

Here is an example:

<div id="stringContainer"></div>

var searchstring = "Luminous&#160;Arc&#160;2";
searchstring = searchstring.replace(/&#160;/g, '&nbsp;') // Convert &#160; to &nbsp;

var c = document.getElementById("stringContainer");
c.innerHTML = '<table>'+houses+'</table>';
var h = c.getElementsByTagName('tr');

for(var i = 0, l = h.length; i < l; i++){ 
    var name = h[i].firstChild.nextSibling.getElementsByTagName('nobr')[0]; 
    if(name && name.innerHTML == searchstring){ 
        console.log(h[i].getElementsByTagName('input')[5].value) 
    }
}

Here's a working example

If we assume that the variable houses contains the following data:

var houses = '...'; // Data goes here

Answer 3

Answer №2

After testing your regex with Cerbrus's houses variable, it appears to be functioning correctly.
(Although I included the lazy quantifier ? in [\\s\\S]+, the regex still works without it.)

var house = "Luminous&#160;Arc&#160;2";
var regex = new RegExp( house + "[\\s\\S]+?name=houseid value=([0-9]+)>", "i" );

houses.match( regex )[1];    // "37010"

It seems that either your house variable contains the incorrect value or houses[i] is not accessing the intended string.

Answer 4

After testing your regex with Cerbrus's houses variable, it appears to be functioning correctly.
(Although I included the lazy quantifier ? in [\\s\\S]+, the regex still works without it.)

var house = "Luminous&#160;Arc&#160;2";
var regex = new RegExp( house + "[\\s\\S]+?name=houseid value=([0-9]+)>", "i" );

houses.match( regex )[1];    // "37010"

It seems that either your house variable contains the incorrect value or houses[i] is not accessing the intended string.

Using JavaScript, create a regular expression with variables that can be used to identify and match a specific section of

Answer №1

Answer №2

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