写js代码，使用正则表达式，遍历多行文本，如果一行文本中出现(size:70%),那么删除(size:70%),并用<span style="font-size:70%"><span>包裹这行文本，如果出现(size:80%),那么删除(size:80%),并用<span style="font-size:80%"><span>包裹这行文本。注意数值的变化

好的，以下是一个使用 JavaScript 正则表达式的示例代码：

const text = `
This is a sample text with (size:70%) some text in size 70 
and (size:80%) some in size 80. 
We need to wrap the text in <span> tags based on the size.
`;

// Regular expression to match (size:xx%)
const sizeRegex = /\(size:(\d+)%\)/g;

// Split the text into lines
const lines = text.split("\n");

// Loop through each line of text
for (let i = 0; i < lines.length; i++) {
  const line = lines[i];
  // Find any matches for (size:xx%)
  const matches = line.match(sizeRegex);
  if (matches) {
    for (let j = 0; j < matches.length; j++) {
      const match = matches[j];
      const fontSize = match.match(/\d+/)[0];
      // Remove (size:xx%) from the line
      const updatedLine = line.replace(match, "");
      // Wrap the line in <span> tags with the appropriate font size
      const spanTag = `<span style="font-size:${fontSize}%">${updatedLine}</span>`;
      // Replace the line with the updated line
      lines[i] = spanTag;
    }
  }
}

// Join the lines back together
const updatedText = lines.join("\n");

console.log(updatedText);

这个代码会遍历输入的多行文本，并查找每行中出现的`(size:xx%)`字符串。如果找到了，则会从该行中删除`(size:xx%)`字符串，并使用`<span>`标签包裹该行文本，并设置正确的字体大小。最后，输出更新后的文本。