Extract a string from textfile using JS regex

Question

I'm trying to extract a substring from a file with Javascript Regex. Here is a slice from the file :

Version=2

Format=jpg

Size=1280x960

Date=2013/05/08

Time=23:49:40

Value=250000

I want to extract only Version and Value from the text file. I tried extracting the Version using this but it doesn't return anything.

$('.Content').html().match(/^Version\:(.*)$/g);

$('.Content').html() contains the whole text file.

$('.imageContent').html().match(/^Version\=(.*)$/g); is returning null too — XXDebugger
– XXDebugger, Commented Jun 15, 2015 at 18:51
Remove the anchors.. $('.Content').html().match(/Version=(.*)/g); — karthik manchala
– karthik manchala, Commented Jun 15, 2015 at 18:52
it works. how can I append the other results like I want value and version both . can I append those and then display them separated by new line ? — XXDebugger
– XXDebugger, Commented Jun 15, 2015 at 18:54

karthik manchala · Accepted Answer · 2015-06-15 18:58:45Z

1

You have to remove the anchors or use m flag:

$('.Content').html().match(/Version=(.*)/g);

Or

$('.Content').html().match(/^Version=(.*)$/gm);

Edit: For capturing Value and Version you can do the following:

$('.Content').html().match(/Version=(.*)|Value=(.*)/g);

You will get Version in $1 and Value in $2

See DEMO

edited Jun 15, 2015 at 18:58

answered Jun 15, 2015 at 18:53

karthik manchala

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6 Comments

Mulan Over a year ago

Why are you using g flag?

karthik manchala Over a year ago

@naomik Because OP has many Version's to match... In his first line he said Here is a slice from the file :)

XXDebugger Over a year ago

yes you are right Karthik :) is there any chance I can merge all the result and then display them together ?

karthik manchala Over a year ago

@PSDebugger no sure what you mean by merging all results.. check the update :)

XXDebugger Over a year ago

yes this works and last thing how can I separate each of them by a new line.

|

umka · Accepted Answer · 2015-06-15 18:48:49Z

1

It returns nothing because you're using : in your regex instead of =.

answered Jun 15, 2015 at 18:48

umka

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1 Comment

XXDebugger Over a year ago

$('.imageContent').html().match(/^Version\=(.*)$/g); is returning null too

Mulan · Accepted Answer · 2015-06-15 19:05:53Z

1

If you only need the Version, there's plenty of other answers here.

If you need to parse the entire file, maybe use something like this

var re = /^(\w+)=(.*)$/gm;
var result = {};
var match;

while (match = re.exec(str)) {
  result[match[1]] = match[2];
}

console.log(result.Version);
//=> "2"

console.log(result.Value);
//=> "250000"

console.log(JSON.stringify(result));
// {
//   "Version": "2",
//   "Format": "jpg",
//   "Size": "1280x960",
//   "Date": "2013/05/08",
//   "Time": "23:49:40",
//   "Value": "250000"
// }

answered Jun 15, 2015 at 19:05

Mulan

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Comments

Jahid · Accepted Answer · 2015-06-15 19:22:59Z

0

You can use this regex:

/(Version|Value)=(.*)/gm

answered Jun 15, 2015 at 19:22

Jahid

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Comments

Tuan Anh Hoang-Vu · Accepted Answer · 2015-06-15 19:27:12Z

0

Your regex pattern should be: (replace : by = and remove $ and g at the end)

/^Version=(.*)/

edited Jun 15, 2015 at 19:27

answered Jun 15, 2015 at 18:52

Tuan Anh Hoang-Vu

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7 Comments

Mulan Over a year ago

Why are you using g flag?

Tuan Anh Hoang-Vu Over a year ago

He used that flag. I did not know about his intention so I kept it there.

Mulan Over a year ago

Well he told you his intention was to capture the value after Version.

Tuan Anh Hoang-Vu Over a year ago

Yes, he will be able to do this with the second capture group. The g does not make any difference in this case.

Mulan Over a year ago

If it makes no difference, then why is it there? Write less code™

|

emartinelli · Accepted Answer · 2015-06-15 19:48:49Z

0

Change : for = and add m flag.

^(?:Version|Value)=(.*)$/gm

Demo:

$( document ).ready(function() {
  var re = /^(?:Version|Value)=(.*)$/gm; 
  var str = $('.Content').html();
  var m;
  var result = "";
 
  while ((m = re.exec(str)) !== null) {
      if (m.index === re.lastIndex) {
          re.lastIndex++;
      }
    result += m[1] + ", ";
    
}
  $('#result').text(result);
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="Content">
Version=2

Format=jpg

Size=1280x960

Date=2013/05/08

Time=23:49:40

Value=250000
</div>
<br>
<div id="result">test</div>

answered Jun 15, 2015 at 19:48

emartinelli

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