The session can be used normally locally, but it cannot be used on SAE or the value is null.

The session can be used normally locally, but it cannot be used on SAE or the value is null:

This problem can be solved by placing session_start () in the first line of the Code on the current page.

On the local server, if session_start () is not placed in the first line of the Code, an error is reported, but it can still be used normally. In this case, you can add @ to shield the error display: @ session_start (). On Sae, although you mask the error display through @, it still cannot be used normally and the obtained session value is null. In this case, you only need to set session_start () put it in the first line of the Code on the current page.

The session can be used normally locally, but it cannot be used on SAE or the value is null.