User Friendly Form Validation

[serap]

Hi I have a question which have bothered me for a while - thats to do the validation when a form is submittted:

How can validation be done in the best way? I have come on the alternatives:

1- making the validation in the php after submitting the form
--> then you handle in the server level, but would the data that the user enters still exist when you make a header(location to the same page (probably globals)
--> how would the error messages be handled - would you redirect to a totally new page or the same the user came from?

2 - Using Javascript.
--> This I like because you directly apply messages at the instance data is entered.
--> But this is Client side - so its not a REAL validation.

I like the usability of 2) and the consistency of 1)

But what is the best practice of 1) still having a good user experience???

Im pretty new in PHP/Javascript and web development and do not want to start in a wron direction....

thanks,
Serap

[laserlight]

I dont think there is a best method per se.

Generally, whatever clientside validation you do must be followed by serverside validation anyway.
If the form spans many pages, or if you redirect the user, then there is always the option for sessions.
Otherwise, just process there and then.

[mrhappiness]

what about a combination?

validate the form using javascript if enabled
validate the form with php (even if javascript validation took place)

if the php validation results in errors found reload the page, auto-fill the correct filled fields using their value-attribut and merk the field with erroneuous input