When processing form input in PHP, can I safely assume that all form fields in the submitted form were sent through, or are there some browsers that will not even pass along blank fields?
Sorry if this is a common question, I just can't seem to find the answer.
Remember one rule: Don't trust anything out there!
Do not assume anything check alway everything which comes from a user and validate that values.
But yes normally it is send.
I don't think you should assume that, just because not all requests to your PHP code will always come from the form you crafted; your code should be prepared to handle the case where someone is just making off-hand requests that may not look at all how you expected them to.