const generatedHTML = "tesgddedd
 
 
";

const parser = new DOMParser();
const doc = parser.parseFromString(generatedHTML, "text/html");

// 获取包含直接子img的div元素
// 注意：它也返回其他子元素
const divWithImg = doc.querySelector("div:has(> img)");

if (divWithImg) {
  // 用于在页面上预览
  const code = document.querySelector("code");
  
  // 捕获到带有img的div
  code.textContent = `
    Before:
    ${divWithImg.outerHTML}
   `;
  console.log("Before", divWithImg);
  
  // 添加类名
  divWithImg.className = "myCssClass"
  
  // 更新带有类名的div
  code.textContent += `
    After:
    ${divWithImg.outerHTML}
   `;
  console.log("After", divWithImg);
} else {
  console.log("No match found.");
}