删除除前五个之外的所有匹配项

Question

我有这样的 SVG 代码字符串：

<g class="highcharts-legend"  transform="translate(217,262)">
    <g  clip-path="url(#highcharts-9)">
        <g transform="translate(0,0)">
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>1</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>2</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>3</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>4</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>5</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>6</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>7</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>8</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>9</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>10</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
        </g>
    </g>
</g>

需要删除除前五个之外的所有匹配项<g class="highcharts-legend-item">...</g>。感谢您的帮助！

Answer 1

快速而肮脏：

(?:<g\ class="highcharts-legend-item">.+?</g>[\n\r]){5}\K
(?:<g\ class="highcharts-legend-item">.+?</g>[\n\r])+

参见 a demo on regex101.com 或（更好）改用解析器。

Answer 2

我建议使用 the DOMDocument class for working with svg markup. Here's a fiddle.

<?php

$svg = <<<SVG
<g class="highcharts-legend"  transform="translate(217,262)">
    <g  clip-path="url(#highcharts-9)">
        <g transform="translate(0,0)">
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>1</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>2</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>3</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>4</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>5</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>6</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>7</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>8</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>9</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
            <g class="highcharts-legend-item"><text x="21" y="15"><tspan>10</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"></rect></g>
        </g>
    </g>
</g>
SVG;

$dom = new DOMDocument;
$dom->loadXML($svg);

foreach($dom->getElementsByTagName('g') as $g){
    if($g->getAttribute("class") === "highcharts-legend-item"){
        $items []= $g;
    }
}

for($i = 5; $i < count($items); $i++){
    $items[$i]->parentNode->removeChild($items[$i]);
}

echo $dom->saveXML($dom->documentElement);

<g class="highcharts-legend" transform="translate(217,262)">
   <g clip-path="url(#highcharts-9)">
      <g transform="translate(0,0)">
          <g class="highcharts-legend-item"><text x="21" y="15"><tspan>1</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"/></g>
          <g class="highcharts-legend-item"><text x="21" y="15"><tspan>2</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"/></g>
          <g class="highcharts-legend-item"><text x="21" y="15"><tspan>3</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"/></g>
          <g class="highcharts-legend-item"><text x="21" y="15"><tspan>4</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"/></g>
          <g class="highcharts-legend-item"><text x="21" y="15"><tspan>5</tspan></text><rect x="0" y="4" width="16" height="12" fill="#f7a35c"/></g>





      </g>
   </g>
</g>

删除除前五个之外的所有匹配项

Remove all matches except first five

php

regex

preg-replace