PreMailer.Net 2.7.0

dotnet add package PreMailer.Net --version 2.7.0
                    
NuGet\Install-Package PreMailer.Net -Version 2.7.0
                    
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.
<PackageReference Include="PreMailer.Net" Version="2.7.0" />
                    
For projects that support PackageReference, copy this XML node into the project file to reference the package.
<PackageVersion Include="PreMailer.Net" Version="2.7.0" />
                    
Directory.Packages.props
<PackageReference Include="PreMailer.Net" />
                    
Project file
For projects that support Central Package Management (CPM), copy this XML node into the solution Directory.Packages.props file to version the package.
paket add PreMailer.Net --version 2.7.0
                    
#r "nuget: PreMailer.Net, 2.7.0"
                    
#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package.
#addin nuget:?package=PreMailer.Net&version=2.7.0
                    
Install PreMailer.Net as a Cake Addin
#tool nuget:?package=PreMailer.Net&version=2.7.0
                    
Install PreMailer.Net as a Cake Tool

PreMailer.Net .NET Core build Nuget count

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

Usage

Static method on PreMailer class

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.

Set up PreMailer instance

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

var pm = new PreMailer(htmlSource);
// Optional to add analytics tags
pm.AddAnalyticsTags(source, medium, campaign, content, domain = null);

var result = pm.MoveCssInline(
    removeStyleElements: false,
    ignoreElements: "#ignore",
    preserveMediaQueries: true
);

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

Options

The following options can be passed to the PreMailer.MoveCssInline method to configure its behavior:

  • baseUri(Uri = null) - Base URL to apply to link elements with href values ending with .css.
  • 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).
  • css(string = null) - A string containing a style-sheet for inlining.
  • stripIdAndClassAttributes(bool = false) - True to strip ID and class attributes.
  • removeComments(bool = false) - True to remove comments, false to leave them intact.
  • customFormatter(IMarkupFormatter = null) - Custom formatter to use for the HTML output.
  • preserveMediaQueries(bool = false) - If true and removeStyleElements is true, it will preserve media queries in the style node while removing other CSS, instead of removing the entire style node.
  • useEmailFormatter(bool = false) - If true, empty HTML tags will be preserved as full tags instead of being converted to self-closing tags, and HTML entities like © will be preserved.

External style sheets

Sometimes it's handy to reference external style sheets with a <link href="..." /> element. PreMailer will download and use external style sheets as long as the value of href ends with .css.

Both absolute and relative URLs are supported. If the URL is relative, you must specify the baseUri parameter in either the constructor, or when calling the static MoveCssInline method.

<link /> elements that match the ignoreElements selector won't be downloaded.

Media queries

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 whether 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");

Alternatively, you can use the preserveMediaQueries parameter to keep your media queries while removing other styles:

var result = PreMailer.MoveCssInline(input, removeStyleElements: true, preserveMediaQueries: true);

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

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

Premailer specific CSS becomes HTML attributes

Premailer looks for the use of CSS attributes prefixed with -premailer and will proxy the value through to the DOM element as an attribute.

For example

table {
    -premailer-cellspacing: 5;
    -premailer-width: 500;
}

will make a table element render as

<table cellspacing="5" width="500">

Analytics Tags

The AddAnalyticsTags method can be used to add Google Analytics tracking parameters to links in your HTML:

var pm = new PreMailer(htmlSource);
pm.AddAnalyticsTags(
    source: "newsletter",       // utm_source parameter
    medium: "email",            // utm_medium parameter
    campaign: "summer_sale",    // utm_campaign parameter
    content: "logo_link",       // utm_content parameter
    domain: "example.com"       // Optional: only add tags to links matching this domain
);

This will append ?utm_source=newsletter&utm_medium=email&utm_campaign=summer_sale&utm_content=logo_link to all links, or to links matching the specified domain if provided.

Custom DOM Processing

The Document property provides access to the underlying IHtmlDocument object, allowing you to perform custom DOM manipulation before inlining CSS:

using(var pm = new PreMailer(html)){
  var document = pm.Document;

  // Use AngleSharp to process document before moving css inline...
  
  var result = pm.MoveCssInline();
}

This is useful for advanced scenarios where you need to modify the HTML structure before applying CSS.

Notes

  • Pseudo classes/elements which not supported by external dependencies, or doesn't make sense in email, will be ignored and logged to the InlineResult.Warnings collection.

Installation

NuGet: PreMailer.Net

Contributors

Among others

License

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

Product Compatible and additional computed target framework versions.
.NET net5.0 was computed.  net5.0-windows was computed.  net6.0 was computed.  net6.0-android was computed.  net6.0-ios was computed.  net6.0-maccatalyst was computed.  net6.0-macos was computed.  net6.0-tvos was computed.  net6.0-windows was computed.  net7.0 was computed.  net7.0-android was computed.  net7.0-ios was computed.  net7.0-maccatalyst was computed.  net7.0-macos was computed.  net7.0-tvos was computed.  net7.0-windows was computed.  net8.0 was computed.  net8.0-android was computed.  net8.0-browser was computed.  net8.0-ios was computed.  net8.0-maccatalyst was computed.  net8.0-macos was computed.  net8.0-tvos was computed.  net8.0-windows was computed.  net9.0 was computed.  net9.0-android was computed.  net9.0-browser was computed.  net9.0-ios was computed.  net9.0-maccatalyst was computed.  net9.0-macos was computed.  net9.0-tvos was computed.  net9.0-windows was computed.  net10.0 was computed.  net10.0-android was computed.  net10.0-browser was computed.  net10.0-ios was computed.  net10.0-maccatalyst was computed.  net10.0-macos was computed.  net10.0-tvos was computed.  net10.0-windows was computed. 
.NET Core netcoreapp2.0 was computed.  netcoreapp2.1 was computed.  netcoreapp2.2 was computed.  netcoreapp3.0 was computed.  netcoreapp3.1 was computed. 
.NET Standard netstandard2.0 is compatible.  netstandard2.1 was computed. 
.NET Framework net461 is compatible.  net462 was computed.  net463 was computed.  net47 was computed.  net471 was computed.  net472 was computed.  net48 was computed.  net481 was computed. 
MonoAndroid monoandroid was computed. 
MonoMac monomac was computed. 
MonoTouch monotouch was computed. 
Tizen tizen40 was computed.  tizen60 was computed. 
Xamarin.iOS xamarinios was computed. 
Xamarin.Mac xamarinmac was computed. 
Xamarin.TVOS xamarintvos was computed. 
Xamarin.WatchOS xamarinwatchos was computed. 
Compatible target framework(s)
Included target framework(s) (in package)
Learn more about Target Frameworks and .NET Standard.

NuGet packages (29)

Showing the top 5 NuGet packages that depend on PreMailer.Net:

Package Downloads
Kentico.Xperience.Libraries

The runtime assemblies for libraries and applications that use Kentico Xperience API.

ImmediaC.SimpleCms

ASP.NET Core based CMS

evernote-cloud-sdk-windows

Evernote Cloud SDK for Windows

ActionMailerNext

Package Description

FenixAlliance.ACL.SDK

Application Component for the Alliance Business Suite.

GitHub repositories (6)

Showing the top 6 popular GitHub repositories that depend on PreMailer.Net:

Repository Stars
smartstore/SmartStoreNET
Open Source ASP.NET MVC Enterprise eCommerce Shopping Cart Solution
smartstore/Smartstore
A modular, scalable and ultra-fast open-source all-in-one eCommerce platform built on ASP.NET Core 7
SparkDevNetwork/Rock
An open source CMS, Relationship Management System (RMS) and Church Management System (ChMS) all rolled into one.
TerribleDev/OwinOAuthProviders
OAuth providers for Owin
CervantesSec/cervantes
Cervantes is an open-source, collaborative platform designed specifically for pentesters and red teams. It serves as a comprehensive management tool, streamlining the organization of projects, clients, vulnerabilities, and reports in a single, centralized location.
DigitalRuby/MailDemon
Smtp server for mass emailing, managing email lists and more. Built on .NET Core. Linux, MAC and Windows compatible.
Version Downloads Last updated
2.7.0 3,052 6/5/2025
2.6.0 664,056 5/22/2024
2.5.0 457,953 11/24/2023
2.4.0 3,625,797 11/2/2021
2.3.0 79,482 10/8/2021
2.2.0 3,399,014 4/8/2020
2.1.3 572,489 10/30/2019
2.1.1 74,717 9/16/2019
2.1.0 50,409 9/6/2019
2.0.1 667,610 12/7/2018
2.0.0 993,876 7/18/2018
2.0.0-beta2 97,221 3/21/2017
2.0.0-beta1 2,975 3/21/2017
1.5.5 999,411 11/7/2016
1.5.4 142,666 8/2/2016
1.5.3 83,141 4/15/2016
1.5.2 22,799 4/12/2016
1.5.1 42,932 3/29/2016
1.5.0 26,044 2/23/2016
1.4.3 53,152 12/16/2015
1.4.2 274,599 7/29/2015
1.4.1 45,483 5/22/2015
1.4.0 4,831 5/3/2015
1.3.1 75,851 3/22/2015
1.3.0 70,905 3/1/2015
1.2.9 168,755 11/19/2014
1.2.8 18,453 10/28/2014
1.2.7 292,623 7/28/2014
1.2.6 40,201 5/22/2014
1.2.5 2,551 5/22/2014
1.2.4 120,971 2/18/2014
1.2.3 9,014 11/25/2013
1.2.2 2,815 11/13/2013
1.2.1 2,578 11/12/2013
1.2.0 2,599 11/11/2013
1.1.3 2,982 11/7/2013
1.1.2 17,201 6/5/2012
1.1.1 20,380 11/5/2011
1.1.0 3,926 9/29/2011
1.0.0 6,175 9/12/2011

What's Changed

     * Build(deps): Bump actions/checkout from 4.1.6 to 4.1.7 by @dependabot in https://github.com/milkshakesoftware/PreMailer.Net/pull/409
     * Build(deps): Bump actions/setup-dotnet from 4.0.0 to 4.0.1 by @dependabot in https://github.com/milkshakesoftware/PreMailer.Net/pull/411
     * Build(deps): Bump pascalgn/automerge-action from 0.16.3 to 0.16.4 by @dependabot in https://github.com/milkshakesoftware/PreMailer.Net/pull/412
     * Build(deps): Bump actions/checkout from 4.1.7 to 4.2.0 by @dependabot in https://github.com/milkshakesoftware/PreMailer.Net/pull/413
     * Build(deps): Bump actions/checkout from 4.2.0 to 4.2.1 by @dependabot in https://github.com/milkshakesoftware/PreMailer.Net/pull/414
     * Build(deps): Bump actions/checkout from 4.2.1 to 4.2.2 by @dependabot in https://github.com/milkshakesoftware/PreMailer.Net/pull/415
     * Build(deps): Bump actions/setup-dotnet from 4.0.1 to 4.1.0 by @dependabot in https://github.com/milkshakesoftware/PreMailer.Net/pull/416
     * Build(deps): Bump actions/setup-dotnet from 4.1.0 to 4.2.0 by @dependabot in https://github.com/milkshakesoftware/PreMailer.Net/pull/418
     * Update target frameworks of test and benchmark projects by @martinnormark in https://github.com/milkshakesoftware/PreMailer.Net/pull/420
     * LinkTagCssSource now also downloads content from @import declarations. by @whorchner in https://github.com/milkshakesoftware/PreMailer.Net/pull/419
     * Build(deps): Bump actions/setup-dotnet from 4.2.0 to 4.3.0 by @dependabot in https://github.com/milkshakesoftware/PreMailer.Net/pull/421
     * Build(deps): Bump actions/setup-dotnet from 4.3.0 to 4.3.1 by @dependabot in https://github.com/milkshakesoftware/PreMailer.Net/pull/423
     * Fix #410: Preserve !important tag in inlined styles by @devin-ai-integration in https://github.com/milkshakesoftware/PreMailer.Net/pull/424
     * Fix #347: Preserve HTML entities like &copy; during processing by @devin-ai-integration in https://github.com/milkshakesoftware/PreMailer.Net/pull/425
     * Update README to accurately document PreMailer API by @devin-ai-integration in https://github.com/milkshakesoftware/PreMailer.Net/pull/426
     * Fix #171: Preserve empty HTML tags during serialization by @devin-ai-integration in https://github.com/milkshakesoftware/PreMailer.Net/pull/427
     * Fix CSS comment regex to handle protocol-agnostic URLs in premailer attributes by @devin-ai-integration in https://github.com/milkshakesoftware/PreMailer.Net/pull/428
     * Fix issue #235: Preserve base64 encoded images and URLs during CSS parsing and style application by @devin-ai-integration in https://github.com/milkshakesoftware/PreMailer.Net/pull/429
     
     Full Changelog: https://github.com/milkshakesoftware/PreMailer.Net/compare/v2.6.0...v2.7.0