Regular Expression | Strip specifc HTML Entities

Hi,

We have a requirement to allow specific HTML entities in Text Area and stip out the other HTML entities.

In the text area user can enter allowded HTML entities. If user enters HTML entity other than the allowded HTML entities, then it should be stripped out.

I am trying to write a regex to which will strip the all HTML entities apart from the allowded ones but not successfull.

Any pointer/help in this regard will be appreciated.

Thanks,
A.S.

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vpatel

I am trying to write a regex to which will strip the all HTML entities apart from the allowded ones but not successfull.

What have you tried? At what point and what is failing?

mvusthipalli

Provide the exact information/requirement, I hope we can give you the regular expression Smiley Happy

CRB

Hi,
In the text area user can enter allowded HTML entities. If user enters HTML entity other than the allowded HTML entities, then it should be stripped out.

as others requested, you will need to tell us what is not working for you...

i would say the easiest way, to approach it, is to create a list/array of unwanted HTML entities then run it thru a loop with you regex.

another approach: if these requirements are for all textareas in all forms, look into customizing tinyMCE to do this for you. tinyMCE will remove any html tags/attributes if you remove them from its list of valid entities.

techSan

You may need something of a match and substitute/keep option. But you need to let us know what you've written so far so we can help to get that right.

anjani

Hi All,

Sorry for late reply.

My requirment is to strip all the HTML entities except following :
© ® ¹ ™ and &
from the text area.

I have written the following reges for that :

var entitiesPattern = "&(?!(copy|reg|sup1|trade|amp)\\b)[^&\s\;]*(\ Smiley Wink

";
var entitiesRegularExp = new RegExp(entitiesPattern,"g");
var textAfterEntitiesRemoved = text.replace(entitiesRegularExp,'');

where text contains the content entered in the text area.

But this regex is not working in all the condition. Although its stripping all the unwanted entities.

But its failing in one condition : For example if enter :
"Hello how are you & where are you now days;"
then it strips : "& where are you now days;" from the enterd content and leaves : "Hello how are you".

Could any one please tell me where i am wrong?

Thanks in advance.
A.S.

ISCBorisB

Hi All,

Sorry for late reply.

My requirment is to strip all the HTML entities except following :
© ® ¹ ™ and &
from the text area.

I have written the following reges for that :

var entitiesPattern = "&(?!(copy|reg|sup1|trade|amp)\\b)[^&\s\;]*(\";
var entitiesRegularExp = new RegExp(entitiesPattern,"g");
var textAfterEntitiesRemoved = text.replace(entitiesRegularExp,'');

where text contains the content entered in the text area.

But this regex is not working in all the condition. Although its stripping all the unwanted entities.

But its failing in one condition : For example if enter :
"Hello how are you & where are you now days;"
then it strips : "& where are you now days;" from the enterd content and leaves : "Hello how are you".

Could any one please tell me where i am wrong?

Thanks in advance.
A.S.

Try the following Pattern
"&(?!(copy|reg|sup1|trade|amp))[^&\s\b]+?\;"

anjani

Hi Boris,

Thanks for your quick response.

But the regex is not working in one condition.

© is an allowed entitiy but if i am entering &copyaaaaa; then this is not getting stripped off. I tried to figure out the problem but was not able to do so.

Could you please tell me where is the problem.

Thanks,
A.S.

anjani

Hi Boris,

I tried the following reges and its working.

"&(?!(copy|reg|sup1|trade|amp)\\b)[^&\\s\;]*(\ Smiley Wink

";

Thanks for your help.

A.S.

ISCBorisB

I tried the following reges and its working.

"&(?!(copy|reg|sup1|trade|amp)\\b)[^&\\s\;]*(\";

Either I'm missing something here - or this is the same regex that you've indicated as not working perfectly in your previous post

nipper

It is *slightly* different. \\b and \\s

ISCBorisB

It is *slightly* different. \\b and \\s

I'm not sure but *think* that's just misguided attempts to *escape an escape* for the vBulletin Forum (eg, Forum's
artifact). In any case, \s and \b within regex make sense, \\s and \\b taken verbatim make none whatever (match
reverse slash followed by the letter s or b...)

nipper

I'm not sur but *think* that's just misguided attempts to *escape an escape* for the vBulletin Forum (eg, Forum's
artifact). In any case, \s and \b within regex make sense, \\s and \\b taken verbatim make none whatever (match
reverse slash followed by the letter s or b...)

Yea that was my thought as well. The regex with the \\b would certainly not behave in the way he expects it.

ISCBorisB

Yea that was my thought as well. The regex with the \\b would certainly not behave in the way he expects it.

Double checked his original syntax...

Single slash is perhaps a typo. He needs \s, \b and uses double quotes - which means the String is evaluated
first ( Not only Perl has this notation Smiley Happy

. That in turn means that he has to "escape an escape" in both cases
eg \\s and \\b

anjani

Hi,

Thanks for your replies.

Actually i am using the regex in the javascript. So i am using \\s and \\b to escape \ character.

Thanks,
A.S.