共127节
3.04 自减运算符
<?php
//自增、自减运算符++，--
//1、前自减，先自减，再参与运算
$x1=10;
echo "x1自减前结果".var_dump($x1); //10
echo "<br>";
echo "<br>";
$x2=10;
echo "x2前自减结果".var_dump(--$x2); //9
echo "<br>";
echo "x2前自减后变量结果".var_dump($x2); //9
echo "<br>";
echo "<br>";
$x3=10;
echo "x3前自减运算后结果".var_dump(--$x3-3); //6
echo "<br>";
echo "x3前自减后变量结果".var_dump($x3); //9
echo "<br>";
echo "<br>";
echo "<br>";
//2、后自减，先运算，再参与自增
$y1=10;
echo "y1自减前结果".var_dump($y1); //10
echo "<br>";
echo "<br>";
$y2=10;
echo "y2后自减结果".var_dump($y2--); //10
echo "<br>";
echo "y2后自减后变量结果".var_dump($y2); //9
echo "<br>";
echo "<br>";
$y3=10;
echo "y3后自减运算后结果".var_dump($y3--+3); //13
echo "<br>";
echo "y3后自减后变量结果".var_dump($y3); //9
echo "<br>";
?>
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