在PHP生成HTML中需要帮助

Question

I was learning to validate form data. 我正在学习验证表单数据。 When I had to write this: 当我不得不写这个时：

"<"form method="post" action=""<"php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>"

but when I write this, in output, there is a "> showing at the top of the page. Why? 但是当我编写此代码时，在输出中，页面顶部显示一个"> ，为什么？

Answer 1

Assuming, there is an echo or a print .Change this: 假设有echo或print更改此：

echo "form method="post" action=""<"php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>"

to this: 对此：

echo '<form method="post" action="' . $_SERVER['PHP_SELF'] . '">';