Create an HTML <details> Element Online

The HTML Details Generator creates a native disclosure widget with a <details> container and a <summary> label. Enter the summary and additional text, then choose whether the content is initially open; all outputs update together.

The summary remains visible in both states and lets users expand or collapse the additional content. The generated widget uses native browser interaction without requiring JavaScript.



Create HTML <details> and <summary> in C#

The C# panel shows how to create the configured disclosure widget with Aspose.HTML for .NET . The generated code follows this workflow:

  1. Create an HTMLDocument .
  2. Create details and summary elements with CreateElement() .
  3. Assign the summary and additional text through TextContent and CreateTextNode() , then add open when selected.
  4. Connect the nodes with AppendChild() and write details.html with Save() .

Enter the visible summary and disclosure content before copying the C# code.


HTML Details Generator FAQ

1. What is the purpose of the HTML <details> element?

It creates a native disclosure widget that users can expand to reveal additional information or controls and collapse when that content is not needed.

2. Where should <summary> appear inside <details>?

The <summary> that labels the disclosure should be the first <summary> child of <details>. Content after it forms the additional information shown when the disclosure is open.

3. What does the open attribute mean?

It is a boolean attribute. When present, both the summary and additional content are initially visible; when absent, only the summary is initially shown.

4. Does a details widget require JavaScript?

No. Browsers provide native pointer and keyboard interaction for expanding and collapsing it. JavaScript is needed only for additional application behavior, such as responding to its toggle event.

5. When should I use <details> instead of <dialog>?

Use <details> for optional content that expands within the normal document flow. Use <dialog> for a separate dialog interaction that may need modal behavior, focus handling, and explicit close controls.


Get Started with Aspose.HTML for .NET API

Install Aspose.HTML for .NET from NuGet with the .NET CLI:

dotnet add package Aspose.HTML

You can also use the NuGet Package Manager UI or run Install-Package Aspose.HTML in the Package Manager Console. See the installation guide for setup details, or request a temporary license to evaluate the API without evaluation limitations.