JS: String.prototype.substring

By Xah Lee. Date: . Last updated: .

str.substring(start, end)

Same as str.slice(start, end) but if any argument is negative, it is replaced with 0, and if any argument is greater than length, it's replaced by length.

[see JS: String.prototype.slice]

const ss = "abcd";

console.log ( ss.substring(1,3) ); // bc

console.log ( ss.substring(0, ss.length) ); // abcd
console.log ( ss.substring() ); // abcd
console.log ( ss.substring(1) ); // bcd

console.log ( ss.substring(-1) ); // abcd
console.log ( ss.substring(-2) ); // abcd

JS substring

  1. JS: String.prototype.slice
  2. JS: String.prototype.substring
  3. JS: String.prototype.substr

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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