Make an if statement shorter
Hay all, I have an if
statement. How could I make this as short as possible?
if ( $a < 0 ){
if( $a > -2 ){
echo "standard";
}elseif( $a <= -2 && $a > -4 )开发者_JAVA百科{
echo "thin";
}elseif( $a <= -4 ){
echo "super thin";
}
}else{
if( $a < 2 ){
echo "standard";
}
if( $a > 2.01 && $a <= 4){
echo "thin";
}
if( $a > 4.01 && $a <= 8.00){
echo "super thin";
}
}
EDIT: basically $a
will be any number (positive or negative) and we match it like this.
If the value is
- +0.00 to +/- 2.00 – Standard
- +/- 2.25 to +/- 4.00 – Thin
- +/- 4.25 to +/- 8.00 – Super Thin
Extra marks for anyone who knows what this might be used for :)
You can shorten it by using the absolute value:
$b = abs($a);
if ($b <= 2) {
echo "standard";
} else if ($b <= 4) {
echo "thin";
} else if ($b <= 8) {
echo "super thin";
}
What about this:
$a = abs($a);
if($a<=2) echo "standard";
elseif($a<=4) echo "thin";
elseif($a<=8) echo "super thin";
This is about as simple as it gets:
<?php
$b = abs($a);
$ranges = array(
'standard' => 2,
'thin' => 4,
'super thin' => 8
);
foreach($ranges as $range=>$max) {
$size = $range;
if($b > $max) continue;
break;
}
?>
Or you can keep the actual ranges, allow the range ends to be different (rather than just the absolute values), and allow easy inclusion of additional ranges:
$ranges = array(
'standard' => array(-2, 2),
'thin' => array(-4, 4),
'super thin' => array(null,8),
);
foreach($ranges as $key => $range) {
if((is_null($range[0]) || $a => $range[0]) && (is_null($range[1]) || $a <= $range[1])) {
echo $key;
break;
}
}
The first matching range in the list is the one that qualifies.
if ( $a < 0 )
{
if( $a > -2 ) echo "standard";
elseif($a > -4) echo "thin";
else echo "super thin";
}
else
{
if( $a < 2 ) echo "standard";
elseif( $a > 2.01 && $a <= 4) echo "thin";
elseif( $a > 4.01 && $a <= 8.00) echo "super thin";
}
Its always better to use switch
rather than else if
! It makes the code cleaner and extensible.
switch($a) {
case (-2 < $a):
case ($a < 2):
$r = 'Standard';
break;
case ( 2.25 > $a):
case (-2.25 < $a):
case ($a < 4):
case ($a > -4):
$r = 'Thin';
break;
case ( 4.25 > $a):
case (-4.25 < $a):
case ($a < 8):
case ($a > -8):
$r = 'Super Thin';
break;
default:
$r = 'Out of range';
}
echo $r;
The case expression may be any expression that evaluates to a simple type, that is, integer or floating-point numbers and strings. Arrays or objects cannot be used here unless they are dereferenced to a simple type.
Taken from the documentation at http://us3.php.net/manual/en/control-structures.switch.php
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