正则表达式用于获取javascript中的特定嵌套元素

const regex = /<section .*?class="product".*?>\s*<h3>\s*(.+?)\s*<\/h3>.*?<\/section>\s*|<art .*?id="src".*?>/gs;
const str = `<art id="src">
  <section class="product">
    <h3>xvd</h3>
    <p>
     sjfdsjvdvds
    </p>
  </section>
  <section class="product">
    <h3>avdsvd</h3>
    <p>
    djsfdsjgdjs
    </p>
  </section>
  <section class="product">
    <h3>zdvdsv</h3>
    <p>
 safdgdsghhrh
    </p>
  </section>
  <section class="product">
    <h3>dd</h3>
    <p>zscsvdsvdsv</p>
  </section>
</art>`;
let m;

while ((m = regex.exec(str)) !== null) {
    // This is necessary to avoid infinite loops with zero-width matches
    if (m.index === regex.lastIndex) {
        regex.lastIndex++;
    }
    
    // The result can be accessed through the `m`-variable.
    m.forEach((match, groupIndex) => {
        console.log(`Found match, group ${groupIndex}: ${match}`);
    });
}