what the difference between rewrite rule and redirect rule?

Question

in ISAPI rewrite rules (IIS7):

does [NC,L,R=301] means redirect and [NC,L] means only viewing other address to the user?

Does the first keeps the body of any ajax POST call ?

Answer 1

Let's look at the first half of your question first.

does [NC,L,R=301] means redirect and [NC,L] means only viewing other address to the user?

R=301 or simply RP means permanent redirect (RP - Redirect Permanent). Its sending an HTTP status code 301. Its literally telling your browser to "Stop bugging me with and ask for the .

The [NC, L] on the other hand serves little purpose than to (partially)canonicalize the urls by ignoring case (NC). And stating that it's the last rule in the chain (L).

Reference1 Reference2

Any answer to the second part would be incomplete without looking at the complete rule that you are writing. If its just canonicalization you are after, then it should have no bearing on your Ajax POSTs.