window.length

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.

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概要

ウィンドウにおけるフレーム（<frame> か <iframe> 要素のいずれか）の数を返します。

構文

framesCount = window.length;
  • framesCount はフレームの数です。

例

js
if (window.length) {
  // サブフレーム数が 0 でない場合の処理をここに記述
}

仕様書

Specification
HTML
# dom-length-dev