How to give certain numbers color in PHP

[user123454321]

I am trying to learn PHP basics, and I just cant figure out a way to insert color when certain conditions are met. In my  code below, I want to print out red color on lets say, odd numbers from 20-49.

Appreciate your help big time! 

<?php

    for ($i=20; $i<=49; $i++){        
        echo "$i<br>";  
    } 

?>

[gw1500se]

You can use the modulo operator (%). If you divide by 2 the remainder will be zero for  even numbers and non-zero for odd numbers. For example:

if ($i%2>0) {
	echo "<font style=\"color:red\">$i</font>";
}
else {
	echo "<font style=\"color:blue\">$i</font>";
}

 

[ginerjm]

Since PHP doesn't actually "do" color, I would suggest that you use CSS.  Setup a set of colors in your CSS area and then as you loop thru the numbers and create the HTML that will output those, assign a CSS classname.

First the CSS

<style>
  .color_1_10 {color:red;}
  .color_11_20 {color:blue;}
  .color_21_30 {color:green;}
  .color_more {color:black;}
</style>

Now the PHP

 for ($i=20; $i<=49; $i++)
 {        
	switch ($i)
	{
	case <= 10:
		$clsname = 'class_1_10';
		break;
	case <= 20:
		$clsname = 'class_11_20';
		break;
	case <= 30:
		$clsname = 'class_21_30';
		break;
	default:
		$clsname = 'class_more';
		break;
	}
	echo "<span class='$clsname'>$i</span><br>";
}

Note that I used a different range of numbers, but I think you get the idea.

Edited January 29, 2019 by ginerjm

[ginerjm]

PS - since the <font> tag is so-out-of-date, I suggest doing something other than that.

[gw1500se]

I was trying to keep it simple to start. Yes, using CSS is the modern way to do it but your solution does not address the whole question. It does not base the selected color on whether it is odd or even.

[ginerjm]

PS - I goofed in my typing.  The classnames that I assigned are mistyped.  The span line should use class assignments that match those classes I defined in the CSS code part.

As for my misunderstanding the criteria, change the switch code then.  The scheme is still the same.