在 PHP 中，如何折叠 heredoc（此处文档）中的换行符？

Question

出于 CLI 的目的，我想在heredoc（此处文档）中

部分

折叠（忽略换行符）。

目前，我在要折叠的行的末尾使用

%%

，然后使用

str_replace("%%\n",'', $string);

替换它们。但我对此感觉不太舒服。

有没有逃生绳或更聪明的方法？

例如：

<?php

$string=<<<EOL
This is a single long line, and it has to be
in one line, though the SideCI thing (as a 
coding regulation) I have to line break.
But this line stays short.
And this line too.
And the backslash such as \
won't work. Nor /
won't work.
My alternative way is to use %%
strings and replace them later.

EOL;

$string .= 'And I don\'t want to do this ';
$string .= 'to merge strings.';

echo str_replace("%%\n",'', $string);

我得到如下：

This is a single long line, and it has to be
in one line, though the SideCI thing (as a 
coding regulation) I have to line break.
But this line stays short.
And this line too.
And the backslash such as \
won't work. Nor /
won't work.
My alternative way is to use strings and replace them later.
And I don't want to do this to merge strings.

有什么想法吗？

---

目前的结论（2018/01/17）

禁用换行符作为默认行为，并使用

BR

标签来换行。
1.将

PHP_EOL

（换行符）替换为''（空白）。
2.将

BR

标签替换为

PHP_EOL

.

示例代码：

<?php

$string=<<<EOL
This is a single long line, and it has to be
in one line, though the SideCI thing (as a 
coding regulation) I have to line break.<br>
But this line stays short.<br>
And this line too.<br>
My post alternative way was to use %%
chars and replace them later.<br>

EOL;

$string = str_replace(PHP_EOL,'', $string);
$string = str_ireplace(["<br />","<br>","<br/>"], PHP_EOL, $string);

echo $string;

Answer 1

您可以使用

<br>

标签来破坏 HTML 标准来说明您何时需要换行符。对于习惯了 HTML 的人来说，这会感觉更直观……

$string=<<<EOL
This is a single long line, and it has to be
in one line, though the SideCI thing (as a
coding regulation) I have to line break.
But this line stays short.
And this line too.
And the backslash such as \<br>
won't work. Nor /<br>
won't work.<br>
My alternative way is to use %%<br>
strings and replace them later.

EOL;

$string = str_replace(PHP_EOL,'', $string);
$string = str_ireplace(["<br />","<br>","<br/>"], PHP_EOL, $string);
echo $string;

注意使用

PHP_EOL

来使用新行/换行符的正确当前编码或您使用的平台的任何组合。

Answer 2

就我个人而言，我会使用像

{nbr}

这样的东西，因为

%%

看起来太笼统了，其中

{nbr}

是“不间断”，而

{...}

在模板中很常见，这只是一个意见。

但我也会使用 regx 而不是 str_replace

preg_replace('/{nbr}[\r\n]+/', '', $str);

这样它匹配

\r

、

\r\n

、

\n

甚至

\n\n

或旧Mac、Windows、Linux和多行结尾。

你可以在这里看到它：

Answer 3

这就是我添加的方式 在 heredoc

<?php
$return_str ='';
$newline_char = "\n";
for($i=0; $i <5 ;$i++)
{

$return_str .= <<<abcd
A random new line $newline_char
abcd;
}
echo $return_str ; 
?>

output: 
A random new line 
A random new line 
A random new line 
A random new line 
A random new line