C# Library for moving CSS to inline style attributes, to gain maximum E-mail client compatibility.

string htmlSource = File.ReadAllText(@"C:\Workspace\testmail.html");

var result = PreMailer.MoveCssInline(htmlSource);

result.Html 		// Resultant HTML, with CSS in-lined.
result.Warnings 	// string[] of any warnings that occurred during processing.

The following options can be passed to the PreMailer.MoveCssInline method to configure it's behaviour:

• removeStyleElements(bool = false) - Removes elements that were used to source CSS (currently, only style is supported).
• ignoreElements(string = null) - CSS selector of element(s) not to inline. Useful for mobile styles (see below).

If you want to apply mobile styles to your e-mail, you should put your mobile specific styles in its own style block that targets the appropriate devices using media queries.

But since you cannot know by the time of sending an e-mail wether or not it will be viewed on a mobile device, the style block that targets mobile devices should not be inlined!

To ignore a style block, you need to specify an ignore selector when calling the MoveCssInline method, like this:

var result = PreMailer.MoveCssInline(input, false, ignoreElements: "#ignore");

And your mobile specific style block should have an ID of ignore:

<style type="text/css" id="ignore">.target { width: 1337px; }</style>

• Pseudo classes/elements are not supported by CsQuery (which PreMailer.Net uses internally). Any that are encountered in your HTML will be ignored and logged to the InlineResult.Warnings collection.

NuGet: PreMailer.Net

• martinnormark
• robcthegeek

Among others

PreMailer.Net is available under the MIT license. See the LICENSE file for more info.