php - 嵌套三级引用

Question

我正在尝试创建一个具有三层嵌套引号的 php 变量。如何围绕"tackEvent"、"downloads"、"all"和进行第三级"nofilter"？我在那里的双引号不起作用。

  $outputList .= "<a href=files/".$content_file ." onClick='_gaq.push
(["_trackEvent", "downloads", "all", "nofilter"]);' >" . $content_name . 
"</a>";

Answer 1

From here:

• Outer quote = " (This marks the beginning and end of the string)
• Inner quote = \" (Escaped as to not flag "beginning/end of string")
• Third-tier quote = ' (Literal quote)
• Fourth-tier quote = \' (Literal quote that will be generated as an escaped outer quote)

Answer 2

• 外报价："
• 内部报价： '
• 三级报价： \"
• 四级报价： "

Answer 3

$outputList .= <<<LINK
<a href="files/$content_file" onClick="_gaq.push(['_trackEvent', 'downloads', 'all', 'nofilter']);">$content_name</a>
LINK;

This is using heredoc syntax.

Answer 4

从手册：

要指定文字单引号，请使用反斜杠 (\) 对其进行转义。要指定文字反斜杠，请将其加倍 (\\)。

这也适用于双引号中的字符串。

$str = "I am a string with a quote that says, \"I like quotes\"";