传值
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function example( $m ){
$m = $m * 5 + 10;
echo "在函数内：\$m = ".$m;
}
$m = 1;
example( $m ) ;
echo "<p>在函数外：\$m = $m <p>" ;
传引用
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function example( &$m ){
$m = $m * 5 + 10;
echo "在函数内：\$m = ".$m;
}
$m = 1;
example( $m ) ;
echo "<p>在函数外：\$m = $m <p>" ;