Is php require better or require_once better?

Is it better to use require or require_once in php?

Which one is more efficient and saves resources?

There are many functions in PHP, and sometimes I don’t know which one to use. I just learned that using strtr is faster than str_replace when changing.

require_once Okay

Then require is obviously more efficient and saves resources

It depends on your needs!

require() can call the same file multiple times without prompting an error. require_once can only call the same file once. If require_once the same file multiple times, an error will be reported and parsing will stop. From this require_once The code after the start will not be parsed!

require_once() OK. Recommended to use.

From the perspective of speed and resource saving, is it better to use require? I don’t know which one everyone uses

If from the performance point of view, require is better, from the code robustness point of view, require_once

My personal preference is require_once, because performance is not a bottleneck

In terms of performance, require() is much higher than require_once().

In addition, require() can help the program maintain a good structural hierarchy, instead of just using require_once() to solve the problem.

require_once() statement includes and runs the specified file during script execution. This behavior is similar to the require() statement, the only difference is that if the code in the file is already included, it will not be included again. See the documentation for require() for how this statement works.

require_once() should be used when the same file may be included more than once during script execution, and you want to ensure that it is only included once to avoid problems such as function redefinition and variable reassignment. .

Please refer to the manual for details.

These two functions are different, so it is not easy to compare. Sometimes you must use require (if you want to call it multiple times), and for some function libraries and class library files, it is also necessary to use require_once, otherwise In a complex environment, it is easy to make mistakes (require_once was introduced precisely because of this)

And the speed difference between the two... really does not need to be considered, Find some SQL optimization in your code and display less useless information, which is much more effective than changing 100 require_once.

Another:

Why is strtr better than str_replace Fast?

All I saw in the comments on PHP Manual are that str_replace is much faster, and the two will have different characteristics under certain conditions, so They are not interchangeable in any situation, see the manual for details.

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