PHP什么是更快的{$ code}或。$ code？

Question

I dont know how i can test it.

What is faster in PHP:

$test = "Text {$code}";

or

$test = "Text ".$code;

?

Answer 1

In the real world, you will never notice any difference, so don't stress about it :)

It's unlikely you will experience any noticeable speed problems with either of your options, but let me explain the differences anyway and what the quickest solution would be.

When you use double quotes "like this" php will attempt to evaluate any text within the quotes, which is why you can use {$code} within it, you could of course also miss out the curly brackets and simply write "Text $code" unless there is something more complex than a simple variable being evaluated.

Your second example I expect would be marginally slower (I don't have evidence of this, but I suppose we could write a simple test for it if required). As it is first attempting to evaluate the string, THEN concatenating a variable to the string, this is a separate operation.

If speed is your real concern, then use single quotes. The contents of these will never be evaluated, so you can simply take the text string and concatenate the variable.

Like this:

$test = 'Text ' . $code

Answer 2

Your first option is the fastest:

Benchmarks run against PHP 5.2 and 5.3 show that parsing double-quoted strings with interpolation is no slower (and often faster) than single- quoted strings using concatenation. When simple strings with no variables in them are used, the performance is clearly better with double-quoted strings due to implementation details in the engine.

Reference here