Is this a valid statement?

[Anon]

Would this statement work:

if ("!$password || !$confirm || !username || !$email || !$real_name") {

echo ("You didn't complete every field...<a href="signup.php3">Go back</a>") } else { .. rest of statement

[Anon]

Why to you ask? Did you not even try it yet and see that it
didn't do what you wanted?

In the process of evaluating the if() construct, here's (more or less)
what happens:

<ol><li>The quoted string is processed, expending any $variables in it. (If a particular $variable does not exist, it's replaced by an empty string.)<li>The result is a single string:<br>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;if ("something...") <li>The PHP interpreter most certainly does not look inside the string a second time to see if it can evaluate the contents of the string as a logical expression<li>Rather, the expression is simply <b>if</b> followed by a non-empty string, which has a value of <b>true</b> in this context, so the if always succeeds.</ol>

I don't think there is a shortcut to separately testing every field. Fortunately, this is merely tedious, rather than being actually complicated:

&nbsp;&nbsp;if ( $password == '' // that's two single-quotes here and after
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;|| $confirm == ''
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;|| username == ''
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;|| $email == ''
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;|| $real_name == '')
&nbsp;&nbsp;&nbsp;&nbsp;{
&nbsp;&nbsp;&nbsp;&nbsp;echo "You left something out...";
&nbsp;&nbsp;&nbsp;&nbsp;}

[Anon]

you need to escape the quotes in your href...

if ("!$password || !$confirm || !username || !$email || !$real_name") {

echo ("You didn't complete every field...<a href=\"signup.php3\">Go back</a>") } else { .. rest of statement

[Anon]

I think it's always better to test each element. Although it's tedious, you can give a better error message. You can say "You need to fill in your password" rather than just "go back, you missed something". Know what I mean.

---John Holmes...

[Anon]

But of course; I was just trying to be concise about
the immediate source of the problem.

In "real life" I usually turn all the field titles for missing
files red, in addition to supplying more specific advice
for certain fields (e.g. "that does not appear to be a
valid credit card number", "expiration date is already past",
etc.)

[Anon]

Thanks guys, I think I'll do it individually and just customize it more...