記事編集

日付

ジャンルのカテゴリ―名

タイトル

内容の要旨

<div style="flex: 1 1 0%; display: flex; overflow: hidden; flex-direction: column; height: 368px; box-sizing: border-box; padding: 20px 20px 0px; color: rgb(0, 0, 0); font-family: roboto, helvetica, sans-serif; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;" data-pasted="true"><div style="display: flex; flex: 1 1 0%; position: relative; min-width: 0px; height: 256px; flex-direction: column;"><div tabindex="0" style="color: rgba(0, 0, 0, 0.8); padding: 0px; flex: 1 1 0%; font-size: 16px; line-height: 26px; font-weight: 400; overflow: auto; max-height: 420px;"><p data-bm="35" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 4px; padding: revert; -webkit-line-clamp: revert;">はい、ではこの C# のコード</p><pre data-priority="2" data-bm="36" style="background: none 0% 0% / auto repeat scroll padding-box border-box rgb(249, 249, 249); border: 1px solid rgba(0, 0, 0, 0.1); border-radius: 8px; overflow: hidden;"><div data-bm="60" style="display: flex; height: 28px; flex-direction: row; justify-content: space-between; align-items: center; gap: 8px; padding: 8px 12px; border-bottom: 1px solid rgba(0, 0, 0, 0.1); background: none 0% 0% / auto repeat scroll padding-box border-box rgb(243, 249, 254);"><h5 style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 0px; padding: revert; font-style: normal !important; font-variant: normal !important; font-weight: 400 !important; font-stretch: 100% !important; line-height: 18px; font-family: roboto, helvetica, sans-serif !important; font-optical-sizing: auto !important; font-size-adjust: none !important; font-kerning: auto !important; font-feature-settings: normal !important; font-variation-settings: normal !important; font-language-override: normal !important; font-size: 16px; display: inline-block; color: rgb(11, 73, 127);">Csharp</h5><div style="height: 28px;"><button type="button" tabindex="" title="Copy code" style="box-sizing: border-box; margin: 0px; padding: 0px; font: 400 13px / 20px roboto, helvetica, sans-serif; background-color: rgb(225, 240, 253); border: 1px solid rgba(0, 0, 0, 0); display: grid; color: rgb(0, 0, 0) !important; grid-auto-flow: column; align-items: center; cursor: pointer; text-decoration: none !important; border-radius: 9999px; block-size: 28px; gap: 2px; padding-inline: 10px;"><div style="box-sizing: border-box; margin: 0px; padding: 0px; min-inline-size: 0px; max-inline-size: 100%; white-space: nowrap; text-overflow: ellipsis; overflow: clip; max-block-size: calc(1lh); padding-inline: 2px;">Copy code</div></button></div></div><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255); display: block; white-space: pre-wrap; overflow-wrap: anywhere; padding: 8px 16px 16px;"><span style="color: rgb(215, 58, 73);">if</span> (!paymentTypesByName.TryGetValue(seed.PaymentTypeName, <span style="color: rgb(215, 58, 73);">out</span> <span style="color: rgb(215, 58, 73);">var</span> paymentTypeId))
</code></pre><p data-bm="37" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 4px; padding: revert; -webkit-line-clamp: revert;">を分解して解説します。</p><h2 data-bm="38" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert; font: 22px / 24px roboto, helvetica, sans-serif; height: 32px; -webkit-line-clamp: 1; overflow: hidden; text-overflow: ellipsis; display: -webkit-box; -webkit-box-orient: vertical;">1. <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">paymentTypesByName</code> の正体</h2><ul data-bm="39" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert;"><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;">これは&nbsp;<strong style="font-weight: 700;">辞書型（Dictionary）</strong> の変数である可能性が高いです。<br>例えば：</li></ul><pre data-priority="2" data-bm="40" style="background: none 0% 0% / auto repeat scroll padding-box border-box rgb(249, 249, 249); border: 1px solid rgba(0, 0, 0, 0.1); border-radius: 8px; overflow: hidden;"><div data-bm="61" style="display: flex; height: 28px; flex-direction: row; justify-content: space-between; align-items: center; gap: 8px; padding: 8px 12px; border-bottom: 1px solid rgba(0, 0, 0, 0.1); background: none 0% 0% / auto repeat scroll padding-box border-box rgb(243, 249, 254);"><h5 style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 0px; padding: revert; font-style: normal !important; font-variant: normal !important; font-weight: 400 !important; font-stretch: 100% !important; line-height: 18px; font-family: roboto, helvetica, sans-serif !important; font-optical-sizing: auto !important; font-size-adjust: none !important; font-kerning: auto !important; font-feature-settings: normal !important; font-variation-settings: normal !important; font-language-override: normal !important; font-size: 16px; display: inline-block; color: rgb(11, 73, 127);">Csharp</h5><div style="height: 28px;"><button type="button" tabindex="" title="Copy code" style="box-sizing: border-box; margin: 0px; padding: 0px; font: 400 13px / 20px roboto, helvetica, sans-serif; background-color: rgb(225, 240, 253); border: 1px solid rgba(0, 0, 0, 0); display: grid; color: rgb(0, 0, 0) !important; grid-auto-flow: column; align-items: center; cursor: pointer; text-decoration: none !important; border-radius: 9999px; block-size: 28px; gap: 2px; padding-inline: 10px;"><div style="box-sizing: border-box; margin: 0px; padding: 0px; min-inline-size: 0px; max-inline-size: 100%; white-space: nowrap; text-overflow: ellipsis; overflow: clip; max-block-size: calc(1lh); padding-inline: 2px;">Copy code</div></button></div></div><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255); display: block; white-space: pre-wrap; overflow-wrap: anywhere; padding: 8px 16px 16px;">Dictionary&lt;<span style="color: rgb(227, 98, 9);">string</span>, <span style="color: rgb(227, 98, 9);">int</span>&gt; paymentTypesByName;
</code></pre><p data-bm="41" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 4px; padding: revert; -webkit-line-clamp: revert;">のように、キーが <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">string</code>（支払い方法名）、値が <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">int</code>（支払い方法ID）という構造。</p><h2 data-bm="42" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert; font: 22px / 24px roboto, helvetica, sans-serif; height: 32px; -webkit-line-clamp: 1; overflow: hidden; text-overflow: ellipsis; display: -webkit-box; -webkit-box-orient: vertical;">2. <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">TryGetValue</code> メソッド</h2><ul data-bm="43" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert;"><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;"><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">Dictionary&lt;TKey, TValue&gt;.TryGetValue(key, out value)</code> は、指定したキーが辞書に存在するかを調べ、存在すれば値を <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">out</code> パラメータに格納します。</li><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;">戻り値は <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">bool</code>で、<ul style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert;"><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;"><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">true</code> &rarr; キーが存在し、値が取得できた</li><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;"><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">false</code> &rarr; キーが存在しない</li></ul></li></ul><h2 data-bm="44" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert; font: 22px / 24px roboto, helvetica, sans-serif; height: 32px; -webkit-line-clamp: 1; overflow: hidden; text-overflow: ellipsis; display: -webkit-box; -webkit-box-orient: vertical;">3. <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">out var paymentTypeId</code></h2><ul data-bm="45" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert;"><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;"><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">out</code> は「呼び出し先メソッドから値を受け取る」ための修飾子。</li><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;"><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">var</code> を使うことで、型を自動推論します。<br>例えば辞書が <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">Dictionary&lt;string, int&gt;</code> なら <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">paymentTypeId</code> は <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">int</code> 型になります。</li><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;"><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">out var</code> は C# 7.0 以降で使える構文で、変数宣言と <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">out</code> 引数を同時に行います。</li></ul><h2 data-bm="46" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert; font: 22px / 24px roboto, helvetica, sans-serif; height: 32px; -webkit-line-clamp: 1; overflow: hidden; text-overflow: ellipsis; display: -webkit-box; -webkit-box-orient: vertical;">4. <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">!</code> 演算子</h2><ul data-bm="47" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert;"><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;"><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">!</code> は論理否定（NOT）演算子。</li><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;"><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">TryGetValue(...)</code> が <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">false</code> の場合に <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">!</code> が <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">true</code> になります。</li></ul><h2 data-bm="48" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert; font: 22px / 24px roboto, helvetica, sans-serif; height: 32px; -webkit-line-clamp: 1; overflow: hidden; text-overflow: ellipsis; display: -webkit-box; -webkit-box-orient: vertical;">5. 全体の意味</h2><p data-bm="49" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 4px; padding: revert; -webkit-line-clamp: revert;">この <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">if</code> 文はこういう意味になります：</p><blockquote data-bm="50"><p style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 4px; padding: revert; -webkit-line-clamp: revert;">「<code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">seed.PaymentTypeName</code> というキーが <code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">paymentTypesByName</code> 辞書に存在しない場合、if の中の処理を実行する」</p></blockquote><h3 data-bm="51" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert; display: inline-block; font: 400 20px / 22px roboto, helvetica, sans-serif;">擬似コードで説明</h3><pre data-priority="2" data-bm="52" style="background: none 0% 0% / auto repeat scroll padding-box border-box rgb(249, 249, 249); border: 1px solid rgba(0, 0, 0, 0.1); border-radius: 8px; overflow: hidden;"><div data-bm="62" style="display: flex; height: 28px; flex-direction: row; justify-content: space-between; align-items: center; gap: 8px; padding: 8px 12px; border-bottom: 1px solid rgba(0, 0, 0, 0.1); background: none 0% 0% / auto repeat scroll padding-box border-box rgb(243, 249, 254);"><h5 style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 0px; padding: revert; font-style: normal !important; font-variant: normal !important; font-weight: 400 !important; font-stretch: 100% !important; line-height: 18px; font-family: roboto, helvetica, sans-serif !important; font-optical-sizing: auto !important; font-size-adjust: none !important; font-kerning: auto !important; font-feature-settings: normal !important; font-variation-settings: normal !important; font-language-override: normal !important; font-size: 16px; display: inline-block; color: rgb(11, 73, 127);">Csharp</h5><div style="height: 28px;"><button type="button" tabindex="" title="Copy code" style="box-sizing: border-box; margin: 0px; padding: 0px; font: 400 13px / 20px roboto, helvetica, sans-serif; background-color: rgb(225, 240, 253); border: 1px solid rgba(0, 0, 0, 0); display: grid; color: rgb(0, 0, 0) !important; grid-auto-flow: column; align-items: center; cursor: pointer; text-decoration: none !important; border-radius: 9999px; block-size: 28px; gap: 2px; padding-inline: 10px;"><div style="box-sizing: border-box; margin: 0px; padding: 0px; min-inline-size: 0px; max-inline-size: 100%; white-space: nowrap; text-overflow: ellipsis; overflow: clip; max-block-size: calc(1lh); padding-inline: 2px;">Copy code</div></button></div></div><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255); display: block; white-space: pre-wrap; overflow-wrap: anywhere; padding: 8px 16px 16px;"><span style="color: rgb(106, 115, 125);">// 辞書にキーがあるか確認</span>
<span style="color: rgb(227, 98, 9);">bool</span> found = paymentTypesByName.TryGetValue(seed.PaymentTypeName, <span style="color: rgb(215, 58, 73);">out</span> <span style="color: rgb(215, 58, 73);">var</span> paymentTypeId);

<span style="color: rgb(106, 115, 125);">// found が false &rarr; キーが存在しない</span>
<span style="color: rgb(215, 58, 73);">if</span> (!found) {
    <span style="color: rgb(106, 115, 125);">// キーが見つからなかったときの処理</span>
}
<span style="color: rgb(215, 58, 73);">else</span> {
    <span style="color: rgb(106, 115, 125);">// paymentTypeId に辞書の値が入っている</span>
}
</code></pre><h3 data-bm="53" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert; display: inline-block; font: 400 20px / 22px roboto, helvetica, sans-serif;">例</h3><pre data-priority="2" data-bm="54" style="background: none 0% 0% / auto repeat scroll padding-box border-box rgb(249, 249, 249); border: 1px solid rgba(0, 0, 0, 0.1); border-radius: 8px; overflow: hidden;"><div data-bm="63" style="display: flex; height: 28px; flex-direction: row; justify-content: space-between; align-items: center; gap: 8px; padding: 8px 12px; border-bottom: 1px solid rgba(0, 0, 0, 0.1); background: none 0% 0% / auto repeat scroll padding-box border-box rgb(243, 249, 254);"><h5 style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 0px; padding: revert; font-style: normal !important; font-variant: normal !important; font-weight: 400 !important; font-stretch: 100% !important; line-height: 18px; font-family: roboto, helvetica, sans-serif !important; font-optical-sizing: auto !important; font-size-adjust: none !important; font-kerning: auto !important; font-feature-settings: normal !important; font-variation-settings: normal !important; font-language-override: normal !important; font-size: 16px; display: inline-block; color: rgb(11, 73, 127);">Csharp</h5><div style="height: 28px;"><button type="button" tabindex="" title="Copy code" style="box-sizing: border-box; margin: 0px; padding: 0px; font: 400 13px / 20px roboto, helvetica, sans-serif; background-color: rgb(225, 240, 253); border: 1px solid rgba(0, 0, 0, 0); display: grid; color: rgb(0, 0, 0) !important; grid-auto-flow: column; align-items: center; cursor: pointer; text-decoration: none !important; border-radius: 9999px; block-size: 28px; gap: 2px; padding-inline: 10px;"><div style="box-sizing: border-box; margin: 0px; padding: 0px; min-inline-size: 0px; max-inline-size: 100%; white-space: nowrap; text-overflow: ellipsis; overflow: clip; max-block-size: calc(1lh); padding-inline: 2px;">Copy code</div></button></div></div><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255); display: block; white-space: pre-wrap; overflow-wrap: anywhere; padding: 8px 16px 16px;"><span style="color: rgb(215, 58, 73);">var</span> paymentTypesByName = <span style="color: rgb(215, 58, 73);">new</span> Dictionary&lt;<span style="color: rgb(227, 98, 9);">string</span>, <span style="color: rgb(227, 98, 9);">int</span>&gt;
{
    { <span style="color: rgb(3, 47, 98);">&quot;CreditCard&quot;</span>, <span style="color: rgb(0, 92, 197);">1</span> },
    { <span style="color: rgb(3, 47, 98);">&quot;Cash&quot;</span>, <span style="color: rgb(0, 92, 197);">2</span> }
};

<span style="color: rgb(215, 58, 73);">var</span> seed = <span style="color: rgb(215, 58, 73);">new</span> { PaymentTypeName = <span style="color: rgb(3, 47, 98);">&quot;BankTransfer&quot;</span> };

<span style="color: rgb(215, 58, 73);">if</span> (!paymentTypesByName.TryGetValue(seed.PaymentTypeName, <span style="color: rgb(215, 58, 73);">out</span> <span style="color: rgb(215, 58, 73);">var</span> paymentTypeId))
{
    Console.WriteLine(<span style="color: rgb(3, 47, 98);">&quot;支払い方法が見つかりません&quot;</span>);
}
<span style="color: rgb(215, 58, 73);">else</span>
{
    Console.WriteLine(<span style="color: rgb(3, 47, 98);">$&quot;支払い方法ID: <span style="color: rgb(36, 41, 46);">{paymentTypeId}</span>&quot;</span>);
}
</code></pre><p data-bm="55" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 4px; padding: revert; -webkit-line-clamp: revert;"><strong style="font-weight: 700;">出力:</strong></p><pre data-priority="2" data-bm="56" style="background: none 0% 0% / auto repeat scroll padding-box border-box rgb(249, 249, 249); border: 1px solid rgba(0, 0, 0, 0.1); border-radius: 8px; overflow: hidden;"><div data-bm="64" style="display: flex; height: 28px; flex-direction: row; justify-content: space-between; align-items: center; gap: 8px; padding: 8px 12px; border-bottom: 1px solid rgba(0, 0, 0, 0.1); background: none 0% 0% / auto repeat scroll padding-box border-box rgb(243, 249, 254);"><h5 style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 0px; padding: revert; font-style: normal !important; font-variant: normal !important; font-weight: 400 !important; font-stretch: 100% !important; line-height: 18px; font-family: roboto, helvetica, sans-serif !important; font-optical-sizing: auto !important; font-size-adjust: none !important; font-kerning: auto !important; font-feature-settings: normal !important; font-variation-settings: normal !important; font-language-override: normal !important; font-size: 16px; display: inline-block; color: rgb(11, 73, 127);">
</h5><div style="height: 28px;"><button type="button" tabindex="" title="Copy code" style="box-sizing: border-box; margin: 0px; padding: 0px; font: 400 13px / 20px roboto, helvetica, sans-serif; background-color: rgb(225, 240, 253); border: 1px solid rgba(0, 0, 0, 0); display: grid; color: rgb(0, 0, 0) !important; grid-auto-flow: column; align-items: center; cursor: pointer; text-decoration: none !important; border-radius: 9999px; block-size: 28px; gap: 2px; padding-inline: 10px;"><div style="box-sizing: border-box; margin: 0px; padding: 0px; min-inline-size: 0px; max-inline-size: 100%; white-space: nowrap; text-overflow: ellipsis; overflow: clip; max-block-size: calc(1lh); padding-inline: 2px;">Copy code</div></button></div></div><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255); display: block; white-space: pre-wrap; overflow-wrap: anywhere; padding: 8px 16px 16px;">支払い方法が見つかりません
</code></pre><p data-bm="57" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 4px; padding: revert; -webkit-line-clamp: revert;">💡 <strong style="font-weight: 700;">ポイント</strong></p><ul data-bm="58" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: revert; padding: revert;"><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;"><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">TryGetValue</code> は辞書アクセス時の例外（KeyNotFoundException）を避ける安全な方法。</li><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;"><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">out var</code> は型推論でコードを簡潔にできる。</li><li style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin-top: revert; margin-right: revert; margin-bottom: 8px; margin-left: revert; padding: revert;"><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">!</code> は「見つからなかった場合」を判定するために使われている。</li></ul><p data-bm="59" style="border: 0px; border-collapse: collapse; border-spacing: 0px; list-style-position: initial; list-style-image: initial; list-style-type: revert; margin: 4px; padding: revert; -webkit-line-clamp: revert;">もし必要なら、このコードを<strong style="font-weight: 700;">キーが存在する場合と存在しない場合の両方をテストできるサンプル</strong>としてまとめてお渡しできますが、作りますか？<br>そうすると理解がさらに深まります。</p></div></div></div><div style="color: rgba(0, 0, 0, 0.6); border-top: 0px; margin: 0px 20px; padding: 0px 0px 20px; height: 36px; display: flex; align-items: center; position: relative; font-family: roboto, helvetica, sans-serif; font-size: 14px; font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; white-space: normal; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;"><div style="flex: 1 1 0%; display: flex; gap: 8px; align-items: center;"><button type="button" tabindex="-1" title="Undo" style="box-sizing: border-box; margin: 0px; padding: 0px; font: 700 13px / 20px roboto, helvetica, sans-serif; background-color: rgba(0, 0, 0, 0); border: 1px solid rgba(0, 0, 0, 0); display: grid; color: rgb(0, 0, 0) !important; grid-auto-flow: column; align-items: center; cursor: not-allowed; text-decoration: none !important; opacity: 0.3; block-size: 38px; gap: 4px; padding-inline: 0px; aspect-ratio: 1 / 1; justify-content: center; border-radius: 8px;"><div data-visually-hidden="" style="box-sizing: border-box; margin: 0px; padding: 0px; min-inline-size: 0px; max-inline-size: 100%; white-space: nowrap; text-overflow: ellipsis; overflow: clip; max-block-size: calc(1lh); block-size: 1px; inline-size: 1px; border: 0px; clip-path: inset(50%); position: absolute; padding-inline: 4px;">Undo</div></button><button type="button" tabindex="-1" title="Redo" style="box-sizing: border-box; margin: 0px; padding: 0px; font: 700 13px / 20px roboto, helvetica, sans-serif; background-color: rgba(0, 0, 0, 0); border: 1px solid rgba(0, 0, 0, 0); display: grid; color: rgb(0, 0, 0) !important; grid-auto-flow: column; align-items: center; cursor: not-allowed; text-decoration: none !important; opacity: 0.3; block-size: 38px; gap: 4px; padding-inline: 0px; aspect-ratio: 1 / 1; justify-content: center; border-radius: 8px;"><div data-visually-hidden="" style="box-sizing: border-box; margin: 0px; padding: 0px; min-inline-size: 0px; max-inline-size: 100%; white-space: nowrap; text-overflow: ellipsis; overflow: clip; max-block-size: calc(1lh); block-size: 1px; inline-size: 1px; border: 0px; clip-path: inset(50%); position: absolute; padding-inline: 4px;">Redo</div></button><button type="button" title="Copy" style="box-sizing: border-box; margin: 0px; padding: 0px; font: 700 13px / 20px roboto, helvetica, sans-serif; background-color: rgba(0, 0, 0, 0); border: 1px solid rgba(0, 0, 0, 0); display: grid; color: rgb(0, 0, 0) !important; grid-auto-flow: column; align-items: center; cursor: pointer; text-decoration: none !important; block-size: 38px; gap: 4px; padding-inline: 0px; aspect-ratio: 1 / 1; justify-content: center; border-radius: 8px;"><div data-visually-hidden="" style="box-sizing: border-box; margin: 0px; padding: 0px; min-inline-size: 0px; max-inline-size: 100%; white-space: nowrap; text-overflow: ellipsis; overflow: clip; max-block-size: calc(1lh); block-size: 1px; inline-size: 1px; border: 0px; clip-path: inset(50%); position: absolute; padding-inline: 4px;">Copy</div></button><button type="button" title="Export" style="box-sizing: border-box; margin: 0px; padding: 0px; font: 700 13px / 20px roboto, helvetica, sans-serif; background-color: rgba(0, 0, 0, 0); border: 1px solid rgba(0, 0, 0, 0); display: grid; color: rgb(0, 0, 0) !important; grid-auto-flow: column; align-items: center; cursor: pointer; text-decoration: none !important; block-size: 38px; gap: 4px; padding-inline: 0px; aspect-ratio: 1 / 1; justify-content: center; border-radius: 8px;"><div data-visually-hidden="" style="box-sizing: border-box; margin: 0px; padding: 0px; min-inline-size: 0px; max-inline-size: 100%; white-space: nowrap; text-overflow: ellipsis; overflow: clip; max-block-size: calc(1lh); block-size: 1px; inline-size: 1px; border: 0px; clip-path: inset(50%); position: absolute; padding-inline: 4px;">Export</div></button><div style="display: flex; z-index: 10; align-items: center; gap: 8px; padding: 4px 8px; border-radius: 8px; color: rgba(0, 0, 0, 0.6); width: 300px; min-height: 40px; max-height: 120px; position: absolute; box-sizing: border-box; bottom: 18px; border: 1px solid rgba(0, 0, 0, 0.1); background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255); left: 172px;"><br></div></div></div><p data-f-id="pbf" style="text-align: center; font-size: 14px; margin-top: 30px; opacity: 0.65; font-family: sans-serif;">Powered by <a href="https://www.froala.com/wysiwyg-editor?pb=1" title="Froala Editor">Froala Editor</a></p>

添付画像

画像を変更

Back to List

//検索文：Editor内でHTMLコードをコピーさせる