尖括号<>中间为什么要有问号？

Answer 1

Why is there a question mark between the angle brackets <>? -PHP Chinese website Q&A-Why is there a question mark between the angle brackets <>? -PHP Chinese website Q&A

Please watch and learn.

Answer 2

 固定写法，格式就是这样子滴

Answer 3

这个是php的语法规定，表示的是里面包含的是php代码