正则表达式捕获并替换html标签之外的文本模式

Question

i have some strings like "de456" "us7515", it's de/us and 3 to 10 digits.

I wish to capture all of them and replace them with an hyperlink, unless they are already inside of a html tag.

example:

1. should change:

    <div> de485 </div> => <div> <a href = "xxx.com/de485">de485</a></div> <span> i need us1234 </span> => <span> i need <a href = "xxx.com/us1234"> us1234 </a></span> 

2. should not change:

    <a href ="github.com/xxxxx/us1234> link </a> => <a href ="github.com/xxxxx/us1234> link </a> 

3. should partially change

    <a href ="github.com/xxxxx/us1234> us1234 </a> => <a href ="github.com/xxxxx/us1234> <a href = "xxx.com/us1234"> us1234 </a> </a> 

I already wrote two regex:

to match text pattern:

de456
us1234

/\b(us\d{3,10}|de\d{3,10})\b/ig

to match text pattern inside of open html tag

<a href = "github.com/de456">

/<\s*\w.*\b(us\d{3,10}|de\d{3,10})\b.?>/ig

so I can do 1 and 2 by using jquery regex exec and string.replace, but i don't know how to do 3. Please advise. Thank you very much in advance.

Answer 1

I try this. Please take if necessary.

(?<![\/])((?:de|us)[0-9]{3,10})

SEE DEMO: http://regex101.com/r/oS0tS3/2

Answer 2

The following example is close enough, however, I don't recommend doing this in a real application.

// matches all 3 cases
var pattern = /([^/])((us|de)\d+)/ig;

/* 1 */
'<span> i need us1234 </span>'.replace(pattern, '$1<a href="xxx.com/$2">$2</a>');
//=> "<span> i need <a href="xxx.com/us1234">us1234</a> </span>"

/* 2 */
'<a href ="github.com/xxxxx/us1234> link </a>'.replace(pattern, '$1<a href="xxx.com/$2">$2</a>');
//=> "<a href ="github.com/xxxxx/us1234> link </a>"

/* 3 */
'<a href ="github.com/xxxxx/us1234> us1234 </a>'.replace(pattern, '$1<a href="xxx.com/$2">$2</a>');
//=> "<a href ="github.com/xxxxx/us1234> <a href="xxx.com/us1234">us1234</a> </a>"