In the previous section, you saw what Comparison
Operators were. In this lessons, we'll explore the Comparison Operator for
Not Equal To: !=.
So open up your text editor, and add the following script:
In the next part, we'll have a look at how to use the Less Than ( < ) and Greater Than ( > ) operators.
So open up your text editor, and add the following script:
<?PHP
$correct_username = 'logmein';
$what_visitor_typed = 'logMEin';
$what_visitor_typed = 'logMEin';
if ($what_visitor_typed != $correct_username) {
print("You're not a valid user of this site!");
}
?>
Save your work and try it out. You should be able to guess what it does!
But the thing to note here is the new Comparison Operator. Instead of using
the double equals sign we’re now using an exclamation mark and a single
equals sign. The rest of the If Statement is exactly the same format as you
used earlier.
The things you’re trying to compare need to be different
before a value of true is returned by PHP. In the second variable ($what_visitor_typed),
the letters “ME” are in uppercase; in the first variable, they are
in lowercase. So the two are not the same. Because we used the NOT equal to
operator, the text will get printed. Change your script to this:
$correct_username = 'logmein';
$what_visitor_typed = 'logmein';
$what_visitor_typed = 'logmein';
if ($what_visitor_typed != $correct_username)
{
print("You're not a valid user of this site!");
}
else {
else {
print("Welcome back, friend!");
}
See if you can figure out what has changed. Before you run the script, what
will get printed out?In the next part, we'll have a look at how to use the Less Than ( < ) and Greater Than ( > ) operators.
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