const regex = /<div[^>]*>\d{6}<\/div>/sig;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('<div[^>]*>\\d{6}<\\\/div>', 'sig')
const str = `<div dir="ltr"><br><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr"><br></div><u></u>
<div>
<center id="m_-2051398760120817894wrapper">
<table id="m_-2051398760120817894main" width="100%">
<tbody><tr id="m_-2051398760120817894logo">
<td>
<table width="100%">
<tbody><tr>
<td>
<img src="test.com/logo.png" width="140px" alt="xxxxx Logo" style="padding:0 10px">
</td>
</tr>
</tbody></table>
</td>
</tr>
<tr>
<td height="18px"></td>
</tr>
<tr id="m_-2051398760120817894header">
<td>
<table width="100%">
<tbody><tr>
<td height="64px" style="background-color:#10069f;color:#fff;padding-left:24px;font-weight:700">Reset your password</td>
</tr>
</tbody></table>
</td>
</tr>
<tr id="m_-2051398760120817894content">
<td>
<table width="100%">
<tbody><tr>
<td style="background-color:#f6f5ff;padding:24px 24px 16px 24px">
<p style="margin-top:0">The following is the verification code required to complete your password reset.</p>
<p style="margin-bottom:24px">Enter the following verification code on the screen during the registration, and proceed to the next step.</p>
<div style="display:block;text-align:center;margin-bottom:8px;background-color:#fff;height:92px;font-weight:600;font-size:36px;line-height:92px">191418</div>
<span style="display:block;font-size:12px;color:#5d5d5d">*The verification code is valid only for 24 hours.</span>
</td>
</tr>
</tbody></table>
</td>
</tr>
<tr>
<td height="24px"></td>
</tr>
<tr id="m_-2051398760120817894footer">
<td>
<table width="100%">
<tbody><tr>
<td style="background-color:#6d7777;padding:16px 24px;font-size:12px;color:#fff">
<table width="100%">
<tbody><tr>
<td id="m_-2051398760120817894footer-left">
<span style="display:block">amnimo Inc.</span>
<span style="display:block">0-3-30 usaa-fso, xxxxxxxx-shi, Tokyo, 180-8750, Japan</span>
<span style="display:block">Phone: +81-422-52-6779</span>
<span id="m_-2051398760120817894copyright-mb" style="margin-top:16px">© 2020 <div dir="ltr"><br><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr"><br></div><u></u>
<div>
<center id="m_-2051398760120817894wrapper">
<table id="m_-2051398760120817894main" width="100%">
<tbody><tr id="m_-2051398760120817894logo">
<td>
<table width="100%">
<tbody><tr>
<td>
<img src="https://test.com/logo.png" width="140px" alt="Amnimo Logo" style="padding:0 10px">
</td>
</tr>
</tbody></table>
</td>
</tr>
<tr>
<td height="18px"></td>
</tr>
<tr id="m_-2051398760120817894header">
<td>
<table width="100%">
<tbody><tr>
<td height="64px" style="background-color:#10069f;color:#fff;padding-left:24px;font-weight:700">Reset your password</td>
</tr>
</tbody></table>
</td>
</tr>
<tr id="m_-2051398760120817894content">
<td>
<table width="100%">
<tbody><tr>
<td style="background-color:#f6f5ff;padding:24px 24px 16px 24px">
<p style="margin-top:0">The following is the verification code required to complete your password reset.</p>
<p style="margin-bottom:24px">Enter the following verification code on the screen during the registration, and proceed to the next step.</p>
<div style="display:block;text-align:center;margin-bottom:8px;background-color:#fff;height:92px;font-weight:600;font-size:36px;line-height:92px">191418</div>
<span style="display:block;font-size:12px;color:#5d5d5d">*The verification code is valid only for 24 hours.</span>
</td>
</tr>
</tbody></table>
</td>
</tr>
<tr>
<td height="24px"></td>
</tr>
<tr id="m_-2051398760120817894footer">
<td>
<table width="100%">
<tbody><tr>
<td style="background-color:#6d7777;padding:16px 24px;font-size:12px;color:#fff">
<table width="100%">
<tbody><tr>
<td id="m_-2051398760120817894footer-left">
<span style="display:block">test Inc.</span>
<span style="display:block">2-9-32 ssdsa-sss, puakano-shi, Tokyo, 000-8000, Japan</span>
<span style="display:block">Phone: +81-000-00-652</span>
<span id="m_-2051398760120817894copyright-mb" style="margin-top:16px">© 2020 amnimo Inc.</span>
</td>
<td id="m_-2051398760120817894footer-right">
<span style="display:block">© 2020 amnimo Inc.</span>
</td>
</tr>
</tbody></table>
</td>
</tr>
</tbody></table>
</td>
</tr>
</tbody></table>
</center>
</div>
</div></div> Inc.</span>
</td>
<td id="m_-2051398760120817894footer-right">
<span style="display:block">© 2020 test Inc.</span>
</td>
</tr>
</tbody></table>
</td>
</tr>
</tbody></table>
</td>
</tr>
</tbody></table>
</center>
</div>
</div></div>`;
// Reset `lastIndex` if this regex is defined globally
// regex.lastIndex = 0;
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}`);
});
}
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions