Validate 120 form fields?

akrocks_extreme

I need to validate 120 form fields... So obviously i cant just if each field so i found some code.

while(list($key,$val)=each($_POST)){ 
$$key = $val; 
    if(empty($key)){ 
    echo "Error, one or more fields empty!"; 
    // include the html form again. 
    // include footer if you have one 
    exit(); 
    } 
}

but it doesnt seem to work for me.. does anyone know whats wrong with the code, or have another solution?

LordShryku

The whole variable variable seems useless. If you have no specific validation to do beyond making sure the fields have some sort of value, this should work:

foreach($_POST as $key => $value) {
   if(empty($value)) {
      die($key." was not filled in");
   }
}

akrocks_extreme

thanks!

rachel2004

The problem is not with the code snippet that LordShryku has provided you because that will work as advertised.

You will, however, frustrate your users if they are filling out 120 fields and the script calls a die() function each time the script looks though and finds an empty field.

If I were some visitor to your site and I filled out 110 of your 120 fields and then click submit, I'll get an error message that some field "was not filled in."

Okay, so either your script can redirect me to the form page or I can hit the back button and get there myself. I fill in that one blank field, but I still have those other 9 fields that are blank. So, when I click submit, you script is going to call die() and feed me another message about not having a field filled in.

After a few of these, I can see visitors losing their patience. From your perspective as the web developer, you might think to yourself, "What's the problem? You need to fill in all of the fields."

From the perspective of your visitor however, he is going to hate having to back up for each blank field.

Point I'm trying to make: find a way to set a flag each time field is left blank, but do not call die() if that field is blank.

At the end of the script's run, it should do a check of which form fields were left blank based on your flag. If you have 10 blank fields, you should have 10 flags and the names of those fields that are blank.

You can then redirect your user back to the form page with a custom message for each of those blank fields.

LordShryku

To Rachel's point, you should also do this sort of validation as an onsubmit function in javascript IMHO. Most users will have javascript enabled, so the validation will be performed, and if something is left blank, the functions should return false, preventing the script from being posted. This does not mean you should rely completely on javascript for the validation though.

akrocks_extreme

i see your point.. but i dont think it will be a problem.. they will know to enter everything. its a form to make quizes. i want to validate it first so it doesnt add an empty quiz to the database, if they hit enter ect.

Tekime

You don't think it will be a problem, or it won't be a problem? What if someone is on field 118 and hits Enter by mistake?

Things could get very messy if all you validate is the presence of a value too. The context will help to define the importance of this to you, but it gives me the willies.

I don't care if Zeev himself is sitting here filling out a form with but a single checkbox:

validate, validate, validate!

drag0n

120 fields wow, i would hate to have to fill that out, for money maybe, but for others and whatnot, then thats pretty big, just maybe soemthign you should consider on the marketing and ease of use part.

dave420

I'd tackle this in a different way - I'd create a list of each field in PHP, and associate with those fields any validation that needs to be done (such as matching a pattern, etc.).

I'd then use that list to generate the HTML form itself (personally, via a template), but first I'd check if data has been passed back:

When the document returns data, I'd loop through each returned field, and test it against the criteria. If it passes, fine. If not, I'd set a flag in my list of variables that the field didn't pass validation. When the page is re-drawn using the list, it can add in the "this field is not correct" text or whatever. That way, each time you submit the page, it'll show you every single field that is wrong, and what's wrong with it. You can then fill it out as many times as you need until it's correct.

Relying on javascript is frought with problems. This method is 100% cross-browser, and doesn't rely on anything beyond your control.

akrocks_extreme

ok, i'm going to redo the form stuff, this is just temporary anyways, i did it this way until i figure something out, which i think i figured it out... but anyways, i'm going to strip out illegal characters from the fields, what would some be that could possibly cause problems, like < > or are those a problem?

rachel2004

There are so many PHP scripts (and newsgroup posts) that have been written to validate forms... maybe it might be better to visit some script reponsitories, take one, and customize it your form fields.