はじめに
この方法はWordPressなどで使うと効果的です。
まずはじめに、</body> 直前に下記のScriptを挿入してください。場合によっては<head> ~ </head>内に挿入。
</body>の直前の理由は、少しでも読み込みスピードの足を引っ張らないようにするためです。
ここに関してはあなたのやり方に任せます。
<script>
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</script>
classの挿入、srcの書き換え
次に、遅延読み込みをさせたい対象に次のclassを入れてください
class="lazyload"
最後に src を次のように書き換えてください。
data-src
imgの例
<img data-src="xxx.png" class="lazyload" alt="xxx">
iframe（google map , youtube etc...）の場合も同様の形で書き換え、classの追記をしてください。
おめでとう。これで遅延読み込みの実装は完了だ。
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