Numbers & css classes

How can I add a css class to a randomly generated numb开发者_Go百科er.

example:

if the number is under 2000 add a css class named red to the div <div class="red">500</div>
if the number is over  2000 add a css class named blue to the div <div class="blue">2500</div>

There are many ways this could be done, but here's one simple one. If $rNum holds your randomly-generated number we can test whether it is less than or equal to 2000. If it is, we'll print "red", and if it's not we'll print "blue".

<p class="<?php print ( $rNum <= 2000 ) ? "red" : "blue" ; ?>">Hello World</p>

If you're new to PHP you may find the syntax of the ternary operator to be somewhat confusion. It's basically a simplified inline if-else statement. You can see more examples and read a short description online at php.net.

you can first generate the rand number, store it into a variable and then use if..else to add the class to div element, like below:

<?php $rand = rand($min,$max); ?>
<div class="<?php if ( $rand <= 2000 ) echo "red"; else echo "blue" ; ?>"><?php echo $rand; ?></div>

Alternatively, add an id element to this div tag, and then use Javascript to add the class.

Do you want to do this?

<div class="<?php echo ($number<2000)?'red':'blue'; ?>">
 <?php echo $number ?>
</div>