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<p data-bm="50" 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; color: rgb(10, 12, 15); font-family: Roboto, Helvetica, sans-serif; font-size: 16px; 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">はい、ASP.NET Core MVC で&nbsp;<strong style="font-weight: 700;">wwwroot/Images</strong> フォルダー内のファイル名を取得し、<br><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">SelectList</code> に変換して View に渡すサンプルコードを作成できます。</p><p 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: 4px; padding: revert; -webkit-line-clamp: revert; color: rgb(10, 12, 15); font-family: Roboto, Helvetica, sans-serif; font-size: 16px; 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;">以下は&nbsp;<strong style="font-weight: 700;">完全に動作するサンプル</strong> です。</p><h2 data-bm="52" 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; color: rgb(10, 12, 15); 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;">Controller サンプル</h2><pre data-priority="2" data-bm="53" style="background: none 0% 0% / auto repeat scroll padding-box border-box rgb(245, 245, 245); border-color: rgba(0, 0, 0, 0.1); border-style: solid; border-width: 1px; border-image: none 100% / 1 / 0 stretch; border-radius: 8px; overflow: hidden; color: rgb(10, 12, 15); font-size: 16px; 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; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;"><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(252, 250, 247);"><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(60, 81, 180);">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(217, 223, 251); border-color: rgba(0, 0, 0, 0); border-style: solid; border-width: 1px; border-image: none 100% / 1 / 0 stretch; display: grid; grid-auto-flow: column; align-items: center; cursor: pointer; color: rgb(60, 81, 180) !important; 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);">using</span> Microsoft.AspNetCore.Mvc;
<span style="color: rgb(215, 58, 73);">using</span> Microsoft.AspNetCore.Mvc.Rendering;
<span style="color: rgb(215, 58, 73);">using</span> System.IO;
<span style="color: rgb(215, 58, 73);">using</span> System.Linq;

<span style="color: rgb(215, 58, 73);">namespace</span> <span style="color: rgb(111, 66, 193);">YourApp.Controllers</span>
{
    <span style="color: rgb(215, 58, 73);">public</span> <span style="color: rgb(215, 58, 73);">class</span> <span style="color: rgb(111, 66, 193);">ImageController</span> : <span style="color: rgb(111, 66, 193);">Controller</span>
    {
        <span style="color: rgb(215, 58, 73);">private</span> <span style="color: rgb(215, 58, 73);">readonly</span> IWebHostEnvironment _env;

        <span style="color: rgb(215, 58, 73);">public</span> <span style="color: rgb(111, 66, 193);">ImageController</span>(IWebHostEnvironment env)
        {
            _env = env;
        }

        <span style="color: rgb(215, 58, 73);">public</span> IActionResult <span style="color: rgb(111, 66, 193);">Index</span>()
        {
            <span style="color: rgb(106, 115, 125);">// wwwroot/Images フォルダーの絶対パスを取得</span>
            <span style="color: rgb(227, 98, 9);">string</span> imagesPath = Path.Combine(_env.WebRootPath, <span style="color: rgb(3, 47, 98);">&quot;Images&quot;</span>);

            <span style="color: rgb(106, 115, 125);">// フォルダーが存在しない場合は空のリストを返す</span>
            <span style="color: rgb(215, 58, 73);">if</span> (!Directory.Exists(imagesPath))
            {
                ViewBag.ImageList = <span style="color: rgb(215, 58, 73);">new</span> SelectList(Enumerable.Empty&lt;<span style="color: rgb(227, 98, 9);">string</span>&gt;());
                <span style="color: rgb(215, 58, 73);">return</span> View();
            }

            <span style="color: rgb(106, 115, 125);">// 対象拡張子のファイルを取得（jpg, png, gif）</span>
            <span style="color: rgb(215, 58, 73);">var</span> files = Directory.EnumerateFiles(imagesPath)
                                 .Where(f =&gt; <span style="color: rgb(215, 58, 73);">new</span>[] { <span style="color: rgb(3, 47, 98);">&quot;.jpg&quot;</span>, <span style="color: rgb(3, 47, 98);">&quot;.jpeg&quot;</span>, <span style="color: rgb(3, 47, 98);">&quot;.png&quot;</span>, <span style="color: rgb(3, 47, 98);">&quot;.gif&quot;</span> }
                                 .Contains(Path.GetExtension(f).ToLower()))
                                 .Select(f =&gt; Path.GetFileName(f)) <span style="color: rgb(106, 115, 125);">// ファイル名のみ</span>
                                 .ToList();

            <span style="color: rgb(106, 115, 125);">// SelectList を作成（Value と Text を同じにする例）</span>
            ViewBag.ImageList = <span style="color: rgb(215, 58, 73);">new</span> SelectList(files);

            <span style="color: rgb(215, 58, 73);">return</span> View();
        }
    }
}
</code></pre><h2 data-bm="54" 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; color: rgb(10, 12, 15); 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;">View (Index.cshtml) サンプル</h2><pre data-priority="2" data-bm="55" style="background: none 0% 0% / auto repeat scroll padding-box border-box rgb(245, 245, 245); border-color: rgba(0, 0, 0, 0.1); border-style: solid; border-width: 1px; border-image: none 100% / 1 / 0 stretch; border-radius: 8px; overflow: hidden; color: rgb(10, 12, 15); font-size: 16px; 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; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;"><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(252, 250, 247);"><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(60, 81, 180);">Razor</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(217, 223, 251); border-color: rgba(0, 0, 0, 0); border-style: solid; border-width: 1px; border-image: none 100% / 1 / 0 stretch; display: grid; grid-auto-flow: column; align-items: center; cursor: pointer; color: rgb(60, 81, 180) !important; 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;">@{
    ViewData[&quot;Title&quot;] = &quot;Image Select&quot;;
}

&lt;h2&gt;画像選択&lt;/h2&gt;

&lt;form method=&quot;post&quot;&gt;
    &lt;select asp-items=&quot;ViewBag.ImageList&quot; name=&quot;selectedImage&quot;&gt;&lt;/select&gt;
    &lt;button type=&quot;submit&quot;&gt;送信&lt;/button&gt;
&lt;/form&gt;
</code></pre><h2 data-bm="56" 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; color: rgb(10, 12, 15); 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;">ポイント</h2><ol 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: revert; padding: revert; color: rgb(10, 12, 15); font-family: Roboto, Helvetica, sans-serif; font-size: 16px; 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;"><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;"><strong style="font-weight: 700;"><code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">IWebHostEnvironment.WebRootPath</code></strong> を使うことで&nbsp;<code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">wwwroot</code> の物理パスを取得できます。</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);">Directory.EnumerateFiles()</code> でファイル一覧を取得し、拡張子フィルタをかけています。</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);">Path.GetFileName()</code> でファイル名だけを抽出し、<code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">SelectList</code> に変換しています。</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;">View 側では&nbsp;<code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">asp-items</code> を使って簡単に&nbsp;<code style="border-radius: 8px; background: none 0% 0% / auto repeat scroll padding-box border-box rgb(255, 255, 255);">&lt;select&gt;</code> を生成できます。</li></ol><p 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: 4px; padding: revert; -webkit-line-clamp: revert; color: rgb(10, 12, 15); font-family: Roboto, Helvetica, sans-serif; font-size: 16px; 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;">もし&nbsp;<strong style="font-weight: 700;">ファイル名だけでなく画像のURLも Value にしたい</strong> 場合は、<br>以下のように変更できます。</p><pre data-priority="2" data-bm="59" style="background: none 0% 0% / auto repeat scroll padding-box border-box rgb(245, 245, 245); border-color: rgba(0, 0, 0, 0.1); border-style: solid; border-width: 1px; border-image: none 100% / 1 / 0 stretch; border-radius: 8px; overflow: hidden; color: rgb(10, 12, 15); font-size: 16px; 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; text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;"><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(252, 250, 247);"><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(60, 81, 180);">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(217, 223, 251); border-color: rgba(0, 0, 0, 0); border-style: solid; border-width: 1px; border-image: none 100% / 1 / 0 stretch; display: grid; grid-auto-flow: column; align-items: center; cursor: pointer; color: rgb(60, 81, 180) !important; 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> files = Directory.EnumerateFiles(imagesPath)
                     .Where(f =&gt; <span style="color: rgb(215, 58, 73);">new</span>[] { <span style="color: rgb(3, 47, 98);">&quot;.jpg&quot;</span>, <span style="color: rgb(3, 47, 98);">&quot;.jpeg&quot;</span>, <span style="color: rgb(3, 47, 98);">&quot;.png&quot;</span>, <span style="color: rgb(3, 47, 98);">&quot;.gif&quot;</span> }
                     .Contains(Path.GetExtension(f).ToLower()))
                     .Select(f =&gt; <span style="color: rgb(215, 58, 73);">new</span> {
                         FileName = Path.GetFileName(f),
                         Url = <span style="color: rgb(3, 47, 98);">&quot;/Images/&quot;</span> + Path.GetFileName(f)
                     })
                     .ToList();

ViewBag.ImageList = <span style="color: rgb(215, 58, 73);">new</span> SelectList(files, <span style="color: rgb(3, 47, 98);">&quot;Url&quot;</span>, <span style="color: rgb(3, 47, 98);">&quot;FileName&quot;</span>);
</code></pre><p data-bm="60" 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; color: rgb(10, 12, 15); font-family: Roboto, Helvetica, sans-serif; font-size: 16px; 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;">このコードを使えば、<strong style="font-weight: 700;">wwwroot/Images 内のファイル名を動的に取得してドロップダウンに表示</strong>できます。<br>必要なら、このまま選択した画像をプレビュー表示する機能も追加できます。</p><p data-bm="61" 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; color: rgb(10, 12, 15); font-family: Roboto, Helvetica, sans-serif; font-size: 16px; 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;">もしご希望なら、このサンプルに&nbsp;<strong style="font-weight: 700;">選択した画像を即時プレビューする JavaScript 付きバージョン</strong> を作成できますが、作りますか？</p><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>

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