const regex = /^(?=.*[^\.]$)((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.?){4}$/gmi;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('^(?=.*[^\\.]$)((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\\.?){4}$', 'gmi')
const str = `999.999.999.999
299.299.299.299
199.199.199.344
192.168.1.123
255.255.255.255
0.0.0.0
000.000.000.000
67.98.159.39
087.052.078.23`;
// 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