C# – ASP.NET MVC Html.Encode – New lines


Html.Encode seems to simply call HttpUtility.HtmlEncode to replace a few html specific characters with their escape sequences.

However this doesn't provide any consideration for how new lines and multiple spaces will be interpretted (markup whitespace). So I provide a text area for the a user to enter a plain text block of information, and then later display that data on another screen (using Html.Encode), the new lines and spacing will not be preserved.

I think there are 2 options, but maybe there is a better 3rd someone can suggest.

One option would be to just write a static method that uses HtmlEncode, and then replaces new lines in the resulting string with <br> and groups of multiple spaces with &nbsp;

Another option would be to mess about with the white-space: pre attribute in my style sheets – however I'm not sure if this would produce side effects when Html helper methods include new lines and tabbing to make the page source pretty.

Is there a third option, like a global flag, event or method override I can use to change how html encoding is done without having to redo the html helper methods?

Best Solution

HtmlEncode is only meant to encode characters for display in HTML. It specifically does not encode whitespace characters.

I would go with your first option, and make it an extension method for HtmlHelper. Something like:

public static string HtmlEncode(this HtmlHelper htmlHelper,
                                string text, 
                                bool preserveWhitespace)
    // ...

You could use String.Replace() to encode the newlines and spaces (or Regex.Replace if you need better matching).