This is a fun and easy little mod that displays a thumbnail image with a blog post.  Unlike the mouseover mod I recently added to dbvt.com which pulls a random image from my photo gallery, this mod displays a specific image associated with the post.  The key to the simplicity of the mod is that the image is the post's attachment.

We're adding a new "thumbnail" property to our custom Community Server WeblogData control.  You'll notice that I'm using a custom DBVTConfiguration (as a supplement to CSConfiguration) model to store the default thumbnail for posts that do not include a thumbnail attachment.

case "thumbnail":
    DBVTConfiguration dbvtConfig = DBVTConfiguration.GetConfig();
    string imageUrl = string.Format("<img src=\"{0}\" border=\"0\" />",
         dbvtConfig.DefaultThumbnailUrl);
    if (!post.HasAttachment)
    return imageUrl;

    if (!post.Attachment.ContentType.StartsWith("image"))
    return imageUrl;

    imageUrl = string.Format("<img src=\"{0}\" border=\"0\" />",
            BlogUrls.Instance().AttachmentUrl(post.Weblog, post.Attachment));
    return imageUrl;

Then we modify our postlist page ItemTemplate to display the thumbnail.

<ItemTemplate>
<li class="CommonListRow">
<div class="BlogPostThumbnail">
<DBVTControl:WeblogPostData ID="WeblogPostData3"
         runat="server" Property="Thumbnail"  />
</div>
    <div class="BlogPostArea">
    <h4 class="BlogDirectoryPostHeader">
        <DBVTControl:WeblogPostData ID="WeblogPostData1"
              runat="server" Property="Subject" LinkTo="Post" />
    </h4>
    <div class="BlogPostContent">
        <DBVTControl:WeblogPostData ID="WeblogPostData2"
               Property="Excerpt" runat="server" />
    </div>
    </div>
</li>
</ItemTemplate>