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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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