php - 为什么在 php 中默认不启用缓冲

Question

我想知道 php 中的缓冲。我已经阅读了很多关于此的主题。

How to fix “Headers already sent” error in PHP

Why use output buffering in PHP?

我只阅读了关于优点的信息，没有关于使用缓冲的缺点的信息。

例如

Advantages of output buffering for Web developers

• Turning on output buffering alone decreases the amount of time it takes to download and render our HTML because it's not being sent to the browser in pieces as PHP processes the HTML.
• All the fancy stuff we can do with PHP strings, we can now do with our whole HTML page as one variable.
• If you've ever encountered the message "Warning: Cannot modify header information - headers already sent by (output)" while setting cookies, you'll be happy to know that output buffering is your answer.

如果输出缓冲仅提供优势，为什么我要通过函数 ob_start() 或以任何其他方式手动打开它？

Answer 1

这可能是一个主要基于意见的问题，不应出现在 Stack Overflow 上。

另一方面，我敢说，这个问题有一个简短而明确的答案，可能每个人都会同意我的看法。所以，回答你的问题:

这是因为显式总是比隐式好

引用 Jon Skeet 来自 here :

In general

• Implicit: something is being done for you automatically.

• Explicit: you've written something in the source code to indicate what you want to happen.