const regex = /^(([1-9]?[0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\.){3}([1-9]?[0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])$/gm;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('^(([1-9]?[0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])\\.){3}([1-9]?[0-9]|1[0-9][0-9]|2[0-4][0-9]|25[0-5])$', 'gm')
const str = `172.18.0.25
254.0.24.36
127.0.0.1
127.0.0.256
0.21.02.0214
25.14.23.0
`;
// 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