正则表达式 - 查找匹配内的匹配项

Question

If the string is

<li>Your browser may be missing a required plug-in contained in <a href="http://get.adobe.com/reader/">Adobe Acrobat Reader</a>.  Please reload this page after installing the missing component.<br />If this error persists, you can also save a copy of <a href="test.pdf">

The regex I have written is

/href=.*?.pdf/

This results in capturing the first 'href' and ending with '.pdf'. I need it to start with the second href instead. In other words it should only capture the href that ends with .pdf

How should I go about this using regex?

Answer 1

You can try this regex:

/href=[^>]+\.pdf/

regex101 demo

Most of the time, when you can avoid .* or .+ (or their lazy versions), it's better :)

Also, don't forget to escape periods.