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?

3/26/2013 12:17:11 PM

Accepted Answer

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).

2/7/2009 8:46:07 PM

Using the style="white-space:pre-wrap;" worked for me. Per this article.

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