php questions

1 Which PCRE regular expression will match the string PhP5-rocks?


Answer...
/^[hp1-5]*\-.*/i
/[hp1-5]*\-.?/
/[hp][1-5]*\-.*/
/[PhP]{3}[1-5]{2,3}\-.*$/
/[a-z1-5\-]*/

2 Which of the following are valid PHP variables?
@$foo
&$variable
${0x0}
$variable
$0x0

3 To destroy one variable within a PHP session you should use which method in PHP 5?

4 When comparing two strings, which of the following is acceptable?
$a === $b;
strcasecmp($a, $b);
strcmp($a, $b);
$a == $b;
str_compare($a,$b);


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