short_ open_ Tag short open label must be opened

Today in my CentOS VPS Upper use <?= ?> Instruction pair template PHP When files are exported directly , I found that I couldn't output , So find the reason , Find out CentOS Of php.ini The function of short open label will be turned off by default （Short Open Tag）, That is, you can't use <? ?> label , Just reopen the short open label .

about PHP 5.4 Previous versions , If the short open label is closed , It can't be used anymore <?= ?> It's output , And for PHP 5.4+, Whether the short open label function is turned off or not , You can use <?= ?> For the output .

Specifically CentOS Why do developers want to turn off short open tags in the default configuration , Maybe it's because of the short open label and XML The reason for the file header conflict （<?xml version="1.0"?>）.

Personally feel , To write AJAX In the process , Use JSON Instead of XML It's much more convenient .

In the execution of the project php China Daily syntax error, unexpected end of file in This mistake , We often check whether there is a lack of punctuation and so on .

however , The reason for using the editor , With this error, the editor didn't give feedback , and , Also checked the code carefully , No problem .

At this time, we should think about whether there are problems elsewhere .

New company , stay php The file uses php Segment label for , It's very common . however , The new environment does not necessarily support it .

modify php.ini file ：

short_open_tag = Off by on

short_open_tag effect ：

stay php Configuration file for （php.ini） There is one of them. short_open_tag Value , You can use PHP Segment label for ：(<? ?>).

meanwhile , You can only use it if you turn it on <?= In place of <? echo . stay CodeIgniter This is the way used in the video tutorial of .

But this short label is not recommended , Use <?php ?> Is the standard method . Just because this short label takes a long time , This feature has been preserved .