PHP - 在字符串中连接或直接插入变量 [英] PHP - concatenate or directly insert variables in string

问题描述

我想知道，将 PHP 变量插入字符串的正确方法是什么?

这样:

I am wondering, What is the proper way for inserting PHP variables into a string?

This way:

echo "Welcome ".$name."!"

或者这样:

echo "Welcome $name!"

这两种方法都适用于我的 PHP v5.3.5.后者更短更简单，但我不确定第一个是更好的格式还是被接受为更合适.

Both of these methods work in my PHP v5.3.5. The latter is shorter and simpler but I'm not sure if the first is better formatting or accepted as more proper.

推荐答案

在这两种语法之间，你应该真正选择你喜欢的一种:-)

Between those two syntaxes, you should really choose the one you prefer :-)

就我个人而言，在这种情况下，我会采用您的第二个解决方案(变量插值)，我发现它更易于编写和阅读.

Personally, I would go with your second solution in such a case (Variable interpolation), which I find easier to both write and read.

结果是一样的；即使有性能影响，这些也无关紧要 ¹.

The result will be the same; and even if there are performance implications, those won't matter ¹.

作为旁注，所以我的回答更完整一些:你想要做这样的事情的那一天:

As a sidenote, so my answer is a bit more complete: the day you'll want to do something like this:

echo "Welcome $names!";

PHP 将解释您的代码，就好像您试图使用 $names 变量一样 -- 该变量不存在.- 请注意，它仅在您对字符串使用 "" 而不是 '' 时才有效.

PHP will interpret your code as if you were trying to use the $names variable -- which doesn't exist. - note that it will only work if you use "" not '' for your string.

那天，您需要使用 {}:

echo "Welcome {$name}s!"

无需回退到串联.

还要注意你的第一个语法:

Also note that your first syntax:

echo "Welcome ".$name."!";

可能会优化，避免串联，使用:

Could probably be optimized, avoiding concatenations, using:

echo "Welcome ", $name, "!";

(但是，正如我之前所说，这并不重要......)

_{1 - 除非您要进行数十万次串联与插值 - 否则可能并非如此.}

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