const regex = /^(?:0\.(?:0[1-9]|[1-9]\d?)|[1-9]\d*(?:\.\d{1,2})?)(?:e[+-]?\d+)?$/gmi;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('^(?:0\\.(?:0[1-9]|[1-9]\\d?)|[1-9]\\d*(?:\\.\\d{1,2})?)(?:e[+-]?\\d+)?$', 'gmi')
const str = `0.1
0.01
0.10
0.1e34
0.1e+3
0.1E-2
1.00e3
1.00
23.45
2e34
invalid
0
0.001
12.234
0e34
-1
0.1f45
`;
// 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