<div class="code-block-container"><pre class="language-csharp"><code class="language-csharp">Jil.JSON.Serialize(objects, Jil.Options.PrettyPrint)
</code></pre></div>です。
オプションはいくつかあるので、そこの部分のリンクを置いておきます。 
<iframe id="zenn-embedded__4f0a162e8bea3" src="https://embed.zenn.studio/github#zenn-embedded__4f0a162e8bea3" data-content="https%3A%2F%2Fgithub.com%2Fkevin-montrose%2FJil%2Fblob%2F9276eaa6a0aaea41d280ff01abeed56214f782df%2FJil%2FOptions.cs%23L16" frameborder="0" scrolling="no" loading="lazy"></iframe><a href="https://github.com/kevin-montrose/Jil/blob/9276eaa6a0aaea41d280ff01abeed56214f782df/Jil/Options.cs#L16" style="display:none" target="_blank" rel="nofollow noopener noreferrer">https://github.com/kevin-montrose/Jil/blob/9276eaa6a0aaea41d280ff01abeed56214f782df/Jil/Options.cs#L16</a>

Jil.JSON.Serialize できれいに整形して出力

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