修復其中帶有雙引號的HTML屬性值

Question

我有一組HTML文件，其href屬性的標籤中含有非法語法。例如，

<a name="Conductor, "neutral""></a> 

或

<meta name="keywords" content="Conductor, "hot",Conductor, "neutral",Hot wire,Neutral wire,Double insulation,Conductor, "ground",Ground fault,GFCI,Ground Fault Current Interrupter,Ground fault,GFCI,Ground Fault Current Interrupter,Arc fault circuit interrupter,Arc fault breaker,AFCI," /> 

或

<b>Table of Contents:</b><ul class="xoxo"><li><a href="1.html" title="Page 1: What are "series" and "parallel" circuits?">What are "series" and "parallel" circuits?</a> 

我試圖處理與利用parsefile_html($file_name) Perl的XML::Twig模塊的文件。當讀取具有此語法的文件，它給這個錯誤：

x has an invalid attribute name 'y""' at C:/strawberry/perl/site/lib/XML/Twig.pm line 893 

我需要的是兩種方式，以使模塊接受不良的語法和處理它，或正則表達式查找和替換帶有單引號的屬性中的雙引號。

Answer 1

鑑於你的HTML示例，代碼如下工作：

use Modern::Perl; 

my $html = <<end; 
<meta name="keywords" content="Conductor, "hot",Conductor, "neutral",Hot wire,Neutral wire,Double insulation,Conductor, "ground",Ground fault,GFCI,Ground Fault Current Interrupter,Ground fault,GFCI,Ground Fault Current Interrupter,Arc fault circuit interrupter,Arc fault breaker,AFCI," /> 
<a name="Conductor, "neutral""></a> 
end 

$html =~ s/(?<=content=")(.*?)(?="\s*\/>)/do{my $capture = $1; $capture =~ s|"||g;$capture}/eg; 
$html =~ s/(?<=name=")(.*?)(?="\s*>)/do{my $capture = $1; $capture =~ s|"||g;$capture}/eg; 

say $html; 

輸出：

<meta name="keywords" content="Conductor, hot,Conductor, neutral,Hot wire,Neutral wire,Double insulation,Conductor, ground,Ground fault,GFCI,Ground Fault Current Interrupter,Ground fault,GFCI,Ground Fault Current Interrupter,Arc fault circuit interrupter,Arc fault breaker,AFCI," /> 
<a name="Conductor, neutral"></a> 

我擔心可變長度向後看沒有實現，所以如果有一些空間在等號之前或之後，模式匹配將失敗。但是，頁面最有可能一直創建，所以匹配不會失敗。

當然，首先嚐試替換文件的副本。

Answer 2

我能想到合理安全地執行此操作的唯一方法是使用兩個嵌套評估（/e）替換。下面的程序使用這個想法並且處理你的數據。

外層替換查找字符串中的所有標記，並用包含調整後的屬性值的標記替換它們。

內部結構查找標籤中的所有屬性值，並使用刪除所有雙引號的相同值替換它們。

use strict; 
use warnings; 

my $html = <<'HTML'; 
<meta name="keywords" content="Conductor, "hot",Conductor, "neutral",Hot wire,Neutral wire,Double insulation,Conductor, "ground",Ground fault,GFCI,Ground Fault Current Interrupter,Ground fault,GFCI,Ground Fault Current Interrupter,Arc fault circuit interrupter,Arc fault breaker,AFCI," /> 
<a name="Conductor, "neutral""></a> 
<a href="1.html" title="Page 1: What are "series" and "parallel" circuits?"> 
HTML 

$html =~ s{(<[^>]+>)}{ 

    my $tag = $1; 

    $tag =~ s{ \w+= " \K ([^=<>]+) (?= " (?: \s+\w+= | \s*/?>)) } 
    { 
    (my $attr = $1) =~ tr/"//d; 
    $attr; 
    }egx; 

    $tag; 
}eg; 

print $html; 

輸出

<meta name="keywords" content="Conductor, hot,Conductor, neutral,Hot wire,Neutral wire,Double insulation,Conductor, ground,Ground fault,GFCI,Ground Fault Current Interrupter,Ground fault,GFCI,Ground Fault Current Interrupter,Arc fault circuit interrupter,Arc fault breaker,AFCI," /> 
<a name="Conductor, neutral"></a> 
<a href="1.html" title="Page 1: What are series and parallel circuits?">