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Start your free trialahmed saleh
2,754 Pointswhat the point from require_once and include)once?
hi i'm just wondering , can't we just add the include or the require only 1 time in code then it's not gonna load again ?!
thank you
1 Answer
Ken Alger
Treehouse TeacherAhmed:
In general the usage is as follows:
Use
require
when the file is required by your application, e.g. an important message template or a file containing configuration variables which with without the app would break.
require_once
when the file contains content that would produce an error on subsequent inclusion, e.g.function important() { /* important code */}
is definitely needed in your application but since functions cannot be redeclared should not be included again.
include
when the file is not required and application flow should continue when not found, e.g. great for templates referencing variables from the current scope or something
include_once
optional dependencies that would produce errors on subsequent loading or maybe remote file inclusion that you do not want to happen twice due to the HTTP overhead
The difference between require
and include
is that the require()
function handles errors differently. If an error occurs, the include()
function generates a warning, but the script will continue execution. The require()
generates a fatal error, and the script will stop.
Post back if you have additional questions.
Happy coding,
Ken