Image alt Tag & alt Attribute – Check using C#

Your Gateway to Web Accessibility

Aspose.HTML for .NET empowers developers with the ultimate tool for web accessibility – the alt Tag Checker. Validate alt attributes effortlessly, guaranteeing compliance with WCAG standards. Elevate your coding practices and deliver web content that resonates with users of all abilities!

First, make sure you have Aspose.HTML for .NET installed in your project. The installation process of this library is quite simple. Open the NuGet package manager, search for Aspose.HTML, and install. You may also use the following command from the Package Manager Console:

Install-Package Aspose.HTML

How to Check alt Attributes in C#

Aspose.HTML for .NET introduces the Aspose.Html.Accessibility namespace is dedicated to all web accessibility-related manipulations and checks. Our C# library allows developers to implement alt tag checks while meeting accessibility standards. Easily integrate alt attribute checks into your C# projects, ensuring that web content accessibility is at the forefront. Discover the WCAG compliance of your website effortlessly!

using Aspose.Html;
using Aspose.Html.Accessibility;
using Aspose.Html.Accessibility.Results;
...

    // Prepare a path to a source HTML file
    string documentPath = Path.Combine(DataDir, "test-checker.html");

    // Initialize webaccessibility container
    var webAccessibility = new WebAccessibility();

    // Get from the rules list Principle "1. Perceivable" by code "1" and get guideline "1.1 Text Alternatives"
    var guideline = webAccessibility.Rules.GetPrinciple("1").GetGuideline("1.1");

    // Create an accessibility validator – pass the found guideline as parameters and specify the full validation settings
    var validator = webAccessibility.CreateValidator(guideline, ValidationBuilder.All);

    // Initialize an HTMLDocument object
    using (var document = new HTMLDocument(documentPath))
    {
        var validationResult = validator.Validate(document);
        if (!validationResult.Success)
        {
            // Get all the result details 
            foreach (var ruleResult in validationResult.Details)
            {
                // If the result of the rule is unsuccessful
                if (!ruleResult.Success)
                {
                    // Get errors list
                    foreach (var result in ruleResult.Errors)
                    {
                        // Check the type of the erroneous element, in this case, we have an error in the HTML Element
                        if (result.Error.Target.TargetType == TargetTypes.HTMLElement)
                        {
                            var rule = (HTMLElement)result.Error.Target.Item;
                            Console.WriteLine("Error in rule {0} : {1}", result.Rule.Code, result.Error.ErrorMessage);
                            Console.WriteLine("HTML Element: {0}", rule.OuterHTML);
                        }
                    }
                }
            }
        }
    }

Check alt Tag – Key Features

1. Initializing the Web Accessibility Container. Use the WebAccessibility() constructor to create an instance of the WebAccessibility class.
2. Getting Guideline and Criterion. Specify a guideline to focus on a specific aspect of web accessibility. Call the GetPrinciple() method of the AccessibilityRules class and the GetGuideline() method of the Principle class to get the required principle by code from WCAG against which you want to check the document.
3. Creating an Accessibility Validator. Call the CreateValidator() method to create a validator object.
4. HTML Document Validation. Use the HTMLDocument class to initialize an HTML document for validation. You can load HTML from a file or URL. Use the Validate() method to check the HTML content against the selected criterion. The result is stored in the validationResult variable.
5. Comprehensive Validation. The validation process generates detailed results through the ValidationResult class, providing specific information about the success and failure of rule checks. The detailed insights into WCAG compliance enable you to fine-tune your web content for optimal accessibility.

An alt tag (alt attribute) is an alternative text that describes non-text content such as images, graphs, charts, emojis, buttons, links, etc. Be sure to use alt text to make web content accessible to people with low vision, including people who use screen readers or Braille output devices. Additionally, web accessibility is good for SEO. Google and other search engines use alt texts to improve their understanding of a website’s content, which will lead to higher rankings.

Why Choose Aspose.HTML for .NET

1. Aspose.HTML for .NET has a good reputation and is trusted by developers around the world. It consistently provides high-performance solutions, making it a reliable choice for your web development needs.
2. Continuous library updates will keep you ahead of the curve and compliant with regular updates to accessibility standards.
3. Aspose.HTML for .NET integrates seamlessly into your C# projects, allowing you to focus on developing without the need for a steep learning curve or complex setup.
4. Our support team is always ready to assist you. If you have questions, encounter difficulties, or need advice, please contact Free Support , and we will be happy to help.

How to check alt text of an image – Documentation

The Web Accessibility – How to Check documentation chapter offers a detailed guide on validating an HTML document according to WCAG compliance. Having checked your website, web application, or any other HTML document, you can be sure that people with disabilities will be able to use it effectively. You can check website accessibility for all WCAG compliance or only meet specific criteria. Aspose.HTML for .NET helps you pass these checks.

In the Screen Reader Accessibility – C# Examples article, you will learn how to design your website for screen reader accessibility and how to check alternative text against WCAG guidelines using Aspose.HTML for .NET API.

Image alt Tag Checker – Online App

Aspose.HTML offers the Image alt Tag Checker is a free online tool designed to analyze a website and identify images lacking correct alt attributes. The application scans a webpage, finds images without alt tags, and creates a report indicating which images need descriptive alt attributes.