php - sprintf 参数交换和 HEREDOC

Question

我正在尝试以这种方式在 heredoc 上使用 sprintf。它不会工作。知道如何解决这个问题吗？

$i = <<<EOD
This is your invoice for %1$s %1$s %1$s %1$s
EOD;

$year = '2013';

$i = sprintf($i,$year);

echo $i;

Notice: Undefined variable: s in

Answer 1

因为 HEREDOC 就像一个双引号字符串，PHP 试图将 $s 作为变量插入。尝试 NOWDOC相反

$i = <<<'EOD'
This is your invoice for %1$s %1$s %1$s %1$s
EOD;