php - 替换尚未替换的字符串

Question

所以我有这样的文字:

"word1 word2 word3 etc"

我有一个数组，其中包含一组替换项，我必须像这样携带:

[    
     "word1 word2" => "<a href="someurl">word1 word2</a>",
     "word2"       => "<a href="someurl">word2</a>",
     "word3"       => "<a href="someurl">word3</a>" 
]

基本上我必须为某些单词(或它们的组合)添加一些标签。

我需要避免这种情况，因为“word1 word2”已经被这样替换了:

<a href="someurl">word1 word2</a> word3 etc

我需要避免它变成这样:

"<a href="someurl">word1 <a href="someurl">word2</a></a> word3 etc"
                            ^^^ another replacement inside "word1 word2"

如何避免替换已在其他替换中找到的较小字符串？

使用 str_replace 的实时代码不工作:

$array = [    
     "word1 word2" => "<a href='someurl'>word1 word2</a>",
     "word2"       => "<a href='someurl'>word2</a>",
     "word3"       => "<a href='someurl'>word3</a>" 
];

$txt = "word1 word2 word3 etc";

echo str_replace(array_keys($array),array_values($array),$txt);

http://sandbox.onlinephpfunctions.com/code/85fd62e88cd0131125ca7809976694ee4c975b6b

正确输出:

<a href="someurl">word1 word2</a> <a href="someurl">word3</a> etc

Answer 1

试试这个:

$array = [    
 "word1 word2" => "<a href='someurl'>word1 word2</a>",
 "word2"       => "<a href='someurl'>word2</a>",
 "word3"       => "<a href='someurl'>word3</a>" 
];

 $txt = "word1 word2 word3 etc";

foreach ($array as $word => $replacement) {
   if (!stripos($txt, ">$word<") && !stripos($txt, ">$word") && !stripos($txt, "$word<") ){
    $txt = str_replace($word, $replacement, $txt);
   }
}
echo $txt;

// output: <a href='someurl'>word1 word2</a> <a href='someurl'>word3</a> etc

基本上，在替换单词之前，检查它是否已经包含在标签中