JS: String.prototype.match

By Xah Lee. Date: . Last updated: .

If the argument is a string, it is converted to a RegExp object.

Return a array of captured patterns. Index 0 is the whole matched string, index 1 is first captured pattern.

If there's the global flag g, return a array of all occurrences of matched string.

[see JS: RegExp Syntax]

Return null if no match.

Get Captured Groups

Example of match without global flag. Get all captured groups.

// example of RegExp “match” method, capture groups
// capture the attribute values in a image tag

const xx = '<img class="pict" src="cat.jpg" alt="my cat" width="600" height="400">';

const result = xx.match(/<img class="([^"]+)" src="([^"]+)" alt="([^"]+)" width="([^"]+)" height="([^"]+)">/);

console.log(result[0]); // <img class="i" src="cat.jpg" alt="my cat" width="600" height="400">
console.log(result[1]); // pict
console.log(result[2]); // cat.jpg
console.log(result[3]); // my cat
console.log(result[4]); // 600
console.log(result[5]); // 400

Get All Occurrences

Example of match with global flag. Get all occurrences.

// example of RegExp “match” method with flag g
// get all occurrences

const xx = "google or yahoo for doodle";

console.log(
 xx.match(/.o+/g); // [ 'goo', ' o', 'hoo', 'fo', 'doo' ]
);

console.log(
 xx.match(/x+/g); // null
);

JS RegExp

  1. RegExp Tutorial
  2. RegExp Syntax
  3. Regex Find/Replace

JS String

  1. String Overview
  2. Template String
  3. Char, Code Unit, Codepoint
  4. String Escape Sequence
  5. Unicode Escape Sequence

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