我正在试图弄清楚如何使用preg_match_all和PREG_OFFSET_CAPTURE来解析音乐(文本)选项卡.
Example输入：
[D#] [G#] [Fm]
[C#] [Fm] [C#] [Fm] [C#] [Fm]
[C]La la la la la la [Fm]la la la la [D#]
[Fm]I made this song Cause I [Bbm]love you
[C]I made this song just for [Fm]you [D#]
[Fm]I made this song deep in [Bbm]my heart
我想要获得的输出：
D# G# Fm
C# Fm C# Fm C# Fm
C Fm D#
La la la la la la la la la la
Fm Bbm
I made this song Cause I love you
C Fm D#
I made this song just for you
Fm Bbm
I made this song deep in my heart
最后,我想用html标签包装和弦.
请注意,和弦之间的空格应与原始输入中的和弦的位置完全匹配.
我开始逐行解析输入,检测和弦,得到它们的位置……但我的代码不起作用……
在我的函数line_extract_chords中有一些错误,它不能正常工作.
有任何想法吗 ？
<style>
body{
font-family: monospace;
white-space: pre;
</style>
<?php
function parse_song($content){
$lines = explode(PHP_EOL, $content); //explode lines
foreach($lines as $key=>$line){
$chords_line = line_extract_chords($line);
$lines[$key] = implode("\n\r",(array)$chords_line);
}
return implode("\n\r",$lines);
}
function line_extract_chords($line){
$line_chords = null; //text line with chords, used to compute offsets
$line_chords_html = null; //line with chords links
$found_chords = array();
$line = html_entity_decode($line); //remove special characters (would make offset problems)
preg_match_all("/\[([^\]]*)\]/", $line, $matches, PREG_OFFSET_CAPTURE);
$chord_matches = array();
if ( $matches[1] ){
foreach($matches[1] as $key=>$chord_match){
$chord = $chord_match[0];
$position = $chord_match[1];
$offset= $position;
$offset-= 1; //left bracket
$offset-=strlen($line_chords); //already filled line
//previous matches
if ($found_chords){
$offset -= strlen(implode('',$found_chords));
$offset -= 2*(count($found_chords)); //brackets for previous chords
}
$chord_html = '<a href="#">'.$chord.'</a>';
//add spaces
if ($offset>0){
$line_chords.= str_repeat(" ", $offset);
$line_chords_html.= str_repeat(" ", $offset);
}
$line_chords.=$chord;
$line_chords_html.=$chord_html;
$found_chords[] = $chord;
}
}
$line = htmlentities($line); //revert html_entity_decode()
if ($line_chords){
$line = preg_replace('/\[([^\]]*)\]/', '', $line);
return array($line_chords_html,$line);
}else{
return $line;
}
}
?>
解决方法:
我想提出一个更简单的方法.
它基于这样的假设,即输入数据实际上与您在此处描述的一般可解析.
<style>
.line{
font-family: monospace;
white-space: pre;
margin-bottom:0.75rem;
}
.group{
display: inline-block;
margin-right: 0.5rem;
}
.group .top,
.group .top{
display: block;
}
</style>
<?php
$input = "[D#] [G#] [Fm]
[C#] [Fm] [C#] [Fm] [C#] [Fm]
[C]La la la la la la [Fm]la la la la [D#]
[Fm]I made this song Cause I [Bbm]love you
[C]I made this song just for [Fm]you [D#]
[Fm]I made this song deep in [Bbm]my heart";
$output = '';
$inputLines = explode(PHP_EOL,$input);
foreach($inputLines as $line){
$output .='<div class="line">';
if (!strlen($line)){
$output .= ' ';
}
else{
$inputWords = explode(' ',$line);
foreach($inputWords as $word){
if (preg_match('/^\[(.+)\](.+)$/', $word, $parts)){
$output .='<span class="group"><span class="top">'.$parts[1].'</span><span class="bottom">'.$parts[2].'</span></span>';
}
elseif(preg_match('/^\[(.+)\]$/', $word, $parts)){
$output .='<span class="group"><span class="top">'.$parts[1].'</span><span class="bottom"> </span></span>';
}
else{
$output .='<span class="group"><span class="top"> </span><span class="bottom">'.$word.'</span></span>';
}
}
}
$output .='</div>';
}
die ($output);
这里做的很简单.该脚本仅通过将其包装在HTML中来为和弦数据赋予意义.使用CSS定位和表示.
此外,它还演示了示例和弦转换为示例输出的方式有一点错误.第5行中的Fm D#似乎是一个关闭点.至少我希望如此.
加：
为什么你的代码不起作用.
它实际上做到了.什么不起作用的是它的介绍.你在一行中计算了字母,用另一行中的空格替换了它.正如您所料,这里有两件事无效：
>在基本HTML中,多个连续的空格在brwoser视图中减少到一个
>通常任何浏览器的标准字体都不是等宽字体.因此,没有简单的方法来替换具有相同宽度的空格的字符.
那你怎么办呢？
>通过替换非中断空格()而不是简单的空格,您可以确保所有空白空间实际上都在浏览器视图中表示.正确地做它意味着设置white-space：pre;作为一种风格,所以白色空间得到了实际认可.
>设置等宽字体(font-family：monospace;)以确保替换排列.
它是：
<style>
body{
font-family: monospace;
white-space: pre;
</style>
<?php
function parse_song($content){
$lines = explode(PHP_EOL, $content); //explode lines
foreach($lines as $key=>$line){
$chords_line = line_extract_chords($line);
$lines[$key] = implode("\n\r",(array)$chords_line);
}
return implode("\n\r",$lines);
}
function line_extract_chords($line){
$line_chords = null; //text line with chords, used to compute offsets
$line_chords_html = null; //line with chords links
$found_chords = array();
$line = html_entity_decode($line); //remove special characters (would make offset problems)
preg_match_all("/\[([^\]]*)\]/", $line, $matches, PREG_OFFSET_CAPTURE);
$chord_matches = array();
if ( $matches[1] ){
foreach($matches[1] as $key=>$chord_match){
$chord = $chord_match[0];
$position = $chord_match[1];
$offset= $position;
$offset-= 1; //left bracket
$offset-=strlen($line_chords); //already filled line
//previous matches
if ($found_chords){
$offset -= strlen(implode('',$found_chords));
$offset -= 2*(count($found_chords)); //brackets for previous chords
}
$chord_html = '<a href="#">'.$chord.'</a>';
//add spaces
if ($offset>0){
$line_chords.= str_repeat(" ", $offset);
$line_chords_html.= str_repeat(" ", $offset);
}
$line_chords.=$chord;
$line_chords_html.=$chord_html;
$found_chords[] = $chord;
}
}
$line = htmlentities($line); //revert html_entity_decode()
if ($line_chords){
$line = preg_replace('/\[([^\]]*)\]/', '', $line);
return array($line_chords_html,$line);
}else{
return $line;
}
}
$input = "[D#] [G#] [Fm]
[C#] [Fm] [C#] [Fm] [C#] [Fm]
[C]La la la la la la [Fm]la la la la [D#]
[Fm]I made this song Cause I [Bbm]love you
[C]I made this song just for [Fm]you [D#]
[Fm]I made this song deep in [Bbm]my heart";
die(parse_song($input));
我删除了self :: reference以使其独立运行.
所以你实际上并没有在这里编码任何错误.你刚搞砸了结果的陈述.
尽管如此,你最终会得到一个毫无意义的,几乎无法解释的(也许是解释性的)文本.解析输入的步骤应该着重于赋予数据含义.如果这是HTML或XML标记的方式,甚至是JSON,例如,无关紧要.但是你应该将纯文本转换为结构化数据.
这样你就可以轻松地设计它.您可以识别整个结构的单个部分或将其过滤掉.