Whitespace Trim (Leading & Trailing) in JS
Match leading and/or trailing whitespace on a string — the regex equivalent of .trim().
Try it in the JS tester →Pattern
regexJS
^\s+|\s+$ (flags: g)JavaScript / ECMAScript code
jsJavaScript
const re = new RegExp("^\\s+|\\s+$", "g");
const input = " hello world ";
const matches = [...input.matchAll(re)];
console.log(matches.map(m => m[0]));Uses `String.prototype.matchAll` for global iteration (Node 12+ / all modern browsers).
How the pattern works
^\s+ matches one or more whitespace characters at the start of the string. \s+$ matches one or more whitespace characters at the end. The alternation | with the g flag allows replacing both in a single pass.
Examples
Input
hello world Matches
Input
tabbed Matches
Input
no paddingNo match
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