my if else statement isn't working

adfriedman

The php code below is used to send the results of a form to a mysql database. T1 through T8 are the variables representing the text that people inputed into the form. What's supposed to happen is if they left any of the 5 fields (T1,T2,T3,T6,T8) blank then it shouldn't connect to the database and should print, "you didn't fill out all the info." If they did fill something out for those fields, it should update the database and print, "it finally worked." The problem is, it seems to update the database even if they left fields blank. Does anyone know why.
Thanks for the help
Adam
<?php

If (('$T1'=='') or ('$T2'=='') or ('$T3'=='') or ('$T6'=='') or ('$T8'==''))
{echo "You didn't fill out all the info";}
else
{$db=mysql_connect ("localhost","username","password");
mysql_select_db("observingyourmind_com",$db) or die ("can't connect");
mysql_query("INSERT INTO petition VALUES ('$T1','$T2','$T3','$T4','$T5','$T6','$T7','$T8',0)",$db) or die ("Insert didn't work");
mysql_close ($db) or die ("Can't close");
echo "It finally worked";}
?>

yelvington

Test conditions like this:

('$T1'=='')

... will ALWAYS evaluate false.

Read this page:

http://www.php.net/manual/en/language.types.string.php

The problem is the single quote marks that you have placed around the variable $T1. As the manual explains, "Variables will not be expanded inside a single-quoted string."

The expression should work if you change the quotes to double quotes, but at any rate there is no need to have quotation marks around the variable names at all.

A more economical way of expressing your test would be:

if(!($T1 && $T2 && $T6 && $T8))
echo "Oops! Try again";
else
{ // do stuff
}

This works because PHP considers an empty string to be false.

One more comment: Variable names like $T1 make for hard-to-maintain code.

Anon

Note: if ($T1) will fail if $T1 contains a zero.

It would be better to specify that you do not want an empty string:

if (($T1!='') && ($T2!=''))

Anon

Actually, the best way ,I think, would be:

If (!$T1 || $T2 || $T3|| etc.)
{echo "You didn't fill out all the info";}
else
{$db=mysql_connect ("localhost","username","password");
mysql_select_db("observingyourmind_com",$db) or die ("can't connect");
mysql_query("INSERT INTO petition VALUES ('$T1','$T2','$T3','$T4','$T5','$T6','$T7','$T8',0)",$db) or die ("Insert didn't work");
mysql....

Anon

if (!$T1 || !$t2 || !$T$)

Anon

if (!$T1 || !$t2 || !$T$)

Doesn't anybody teach De Morgan's theorem anymore? This can be (and for clarity should be) rewritten as:

if (! ($T1 && $t2 && $T3) )
   {
   // didn't fill in all vars