Eval problems

[lance]

The following script generates a parse error on the line containing the if statement. This scrip is passed a random number of strings named question_1, question_2 and so on. I am trying to get it to print the contents of each string in order and then exit the while statement after the last string has been processed.

$question_counter = 1;
while($question_counter > 0)
{
$name = "\$question_";
$name .= "$question_counter";
$name = stripslashes($name);
if(isset(eval($name)))
{
print("$name");
$question_counter++;
}//end if
else
{
$question_counter = 0;
}//end else
}//end while

[interactive]

try $QUERY_STRING

[Anon]

Don't use eval. If you are checking whether these variables are set:

$question_1;
$question_2;
etc.

then, just do:

while(...) {
...
$name = ...
...
if(isset($name)) {
print "$name is set";
}
else {
...
}

}

The eval() will evaluate the string as a PHP code. So it will evaluate;

"$question_1"

Just type in $question_1 in a single line by itself in PHP and you'll notice that it does nothing and it has a syntax error (no semicolor) and since you are not performing any operations on $question_1 or declaring it inside a class, the PHP will complain of "expected operator" or "syntax" errors.

-sridhar