javascript字符串正则表达式替换引号之间的字符串

Question

i want to replace all the src attribute inside a string of HTML adding a '?a' at the end of the url to fix a caching issue that i'm having.

So far i got this:

str.replace(/src=".*?"/gi, "src");

But i have no idea how to do the 2nd parameter to get what is matched and add the '?a' at the end.

Example:

<img src="mysite.com/logo.png" /> should become

<img src="mysite.com/logo.png?a" />

Thank you in advance, Daniel!

Answer 1

The first problem is that you are matching the entire src attribute instead of what's within the src attribute.

The second problem is that you aren't putting the match into your replacement.

This would be the correct regex:

str.replace(/src="(.*?)"/gi, 'src="$1?a"')/;

Adding brackets around the match .*? makes sure you match just that part instead of the whole regex, adding $1 into the second parameter makes sure you put the match back into the replacement.

You also have to re-enter src="" into the replacement, because the whole regex match will be replaced.

Answer 2

You can use this /src="(.*?)"/gi regex to find and replace the content.