Using the same userscript to run different code at different URL's

Question

I know it is possible to run a script on different URL's by adding @include statements, but it is possible to run different sets of code based on the URL?

My script currently works properly but I had to break it into 5 separate userscripts and it feels kind of sloppy.

Answer 1

To switch what code runs, per URL, use if() or switch() statements against parts of the location object^Doc.

To avoid false positives and side effects, it is best to just test that property that is most discriminating (usually hostname and/or pathname).

For example, for a script running on different sites:

if (/alice\.com/.test (location.hostname) ) {
    // Run code for alice.com
}
else if (/bob\.com/.test (location.hostname) ) {
    // Run code for bob.com
}
else {
    // Run fall-back code, if any
}

// Run code for all sites here.

Or, for same-site, different pages:

if (/\/comment\/edit/.test (location.pathname) ) {
    // Run code for edit pages
}
else if (/\/comment\/delete/.test (location.pathname) ) {
    // Run code for delete pages
}
else {
    // Run fall-back code, if any
}

// Run code for all pages here.

Note the use of escape \.
.test() is used for the awesome power of regex. For example,
/(alice|bob)\.com/.test (location.hostname).