How can I decode HTML characters in C#?

You can use HttpUtility.HtmlDecode

If you are using .NET 4.0+ you can also use WebUtility.HtmlDecode which does not require an extra assembly reference as it is available in the System.Net namespace.

As @CQ says, you need to use HttpUtility.HtmlDecode, but it's not available in a non-ASP .NET project by default.

For a non-ASP .NET application, you need to add a reference to System.Web.dll. Right-click your project in Solution Explorer, select "Add Reference", then browse the list for System.Web.dll.

Now that the reference is added, you should be able to access the method using the fully-qualified name System.Web.HttpUtility.HtmlDecode or insert a using statement for System.Web to make things easier.

If there is no Server context (i.e your running offline), you can use HttpUtility.HtmlDecode.

Use Server.HtmlDecode to decode the HTML entities. If you want to escape the HTML, i.e. display the < and > character to the user, use Server.HtmlEncode.

Write static a method into some utility class, which accept string as parameter and return the decoded html string.

Include the using System.Web.HttpUtility into your class

public static string HtmlEncode(string text)
    {
        if(text.length > 0){

           return HttpUtility.HtmlDecode(text);
        }else{

         return text;
        }

    }

For .net 4.0

Add a reference to System.net.dll to the project with using System.Net; then use the following extensions

// Html encode/decode
    public static string HtmDecode(this string htmlEncodedString)
    {
        if(htmlEncodedString.Length > 0)
        {
            return System.Net.WebUtility.HtmlDecode(htmlEncodedString);
        }
        else
        {
            return htmlEncodedString;
        }
    }

    public static string HtmEncode(this string htmlDecodedString)
    {
        if(htmlDecodedString.Length > 0)
        {
            return System.Net.WebUtility.HtmlEncode(htmlDecodedString);
        }
        else
        {
            return htmlDecodedString;
        }
    }

For strings containing   I've had to double-decode the string. First decode would turn it into the second pass would correctly decode it to the expected character.