How do you convert a Razor view to a string? - c#

I would like to use my Razor view as some kind of template for sending emails,
so I would like to "save" my template in a view, read it into controller as a string, do some necessary replacements, and then send it.
I have solution that works: my template is hosted somewhere as an HTML page, but I would like to put it into my application (i.e. in my view). I don't know how to read a view as a string in my controller.

I use the following. Put it on your base controller if you have one, that way you can access it in all controllers.
public static string RenderPartialToString(Controller controller, string viewName, object model)
{
controller.ViewData.Model = model;
using (StringWriter sw = new StringWriter())
{
ViewEngineResult viewResult = ViewEngines.Engines.FindPartialView(controller.ControllerContext, viewName);
ViewContext viewContext = new ViewContext(controller.ControllerContext, viewResult.View, controller.ViewData, controller.TempData, sw);
viewResult.View.Render(viewContext, sw);
return sw.GetStringBuilder().ToString();
}
}

Take a look at the RazorEngine library, which does exactly what you want. I've used it before for email templates, and it works great.
You can just do something like this:
// Read in your template from anywhere (database, file system, etc.)
var bodyTemplate = GetEmailBodyTemplate();
// Substitute variables using Razor
var model = new { Name = "John Doe", OtherVar = "Hello!" };
var emailBody = Razor.Parse(bodytemplate, model);
// Send email
SendEmail(address, emailBody);

Related

Access ViewContext.ViewBag without editing the .cshtml view file

I am trying to render a view to html string using the RenderViewToString method below. When calling the viewResult.View.Render and passing the viewContext, it results in the ViewBag being null in the .cshtml view. Example code of my renderer:
public string RenderViewToString(ControllerContext context, string viewName, object model)
{
if (string.IsNullOrEmpty(viewName))
viewName = context.RouteData.GetRequiredString("action");
ViewDataDictionary viewData = new ViewDataDictionary(model);
using (var sw = new StringWriter())
{
ViewEngineResult viewResult = ViewEngines.Engines.FindView(context, viewName, null);
ViewContext viewContext = new ViewContext(context, viewResult.View, viewData, new TempDataDictionary(), sw);
var thisViewBagHasValues = ViewBag;
var thisViewBagIsNull = viewContext.ViewBag;
viewResult.View.Render(viewContext, sw);
return sw.GetStringBuilder().ToString();
}
}
I think by calling the #ViewContext.Controller.ViewBag in the .cshtml file, we can then access the ViewBag data. However, is there a way to access the ViewBag in the .cshtml file without editing the view file? Such as setting a value to the ViewContext.ViewBag before calling the renderer?

Styling Confirmation Email Identity 2.0 MVC 5 [duplicate]

I have designed an Email Template from Razor Syntax. When I send this template as Email using C# code and SMTP protocol, I get bare Razor and HTML markups as Email Body. Am I wrong in this approach? Are Razor Pages allowed as Email Template?
Here is my Page
#inherits ViewPage
#{
Layout = "_Layout";
ViewBag.Title = "";
}
<div class="container w-420 p-15 bg-white mt-40">
<div style="border-top:3px solid #22BCE5"> </div>
<span style="font-family:Arial;font-size:10pt">
Hello <b>{UserName}</b>,<br /><br />
Thanks for Registering to XYZ Portal<br /><br />
<a style="color:#22BCE5" href="{Url}">Click to Confirm Email</a><br />
<br /><br />
Thanks<br />
Admin (XYZ)
</span>
Update..
using (StreamReader reader = new StreamReader(HttpContext.Current.Server.MapPath("~/ContentPages/EmailConfTemplate.cshtml")))
{
body = reader.ReadToEnd();
//Replace UserName and Other variables available in body Stream
body = body.Replace("{UserName}", FirstName);
}
Later On I am replacing the SMTP Code as ..
MailMessage message = new MailMessage(
ApplicationWideData.fromEmailId, // From field
ToEmailId, // Recipient field
"Click On HyperLink To Verify Email Id", // Subject of the email message
body
);
You do not need any special libraries to render a Razor view to a string in an ASP.NET MVC application.
Here is how you do it in MVC Core 3
public static class ViewToStringRenderer
{
public static async Task<string> RenderViewToStringAsync<TModel>(IServiceProvider requestServices, string viewName, TModel model)
{
var viewEngine = requestServices.GetRequiredService(typeof(IRazorViewEngine)) as IRazorViewEngine;
ViewEngineResult viewEngineResult = viewEngine.GetView(null, viewName, false);
if (viewEngineResult.View == null)
{
throw new Exception("Could not find the View file. Searched locations:\r\n" + string.Join("\r\n", viewEngineResult.SearchedLocations));
}
else
{
IView view = viewEngineResult.View;
var httpContextAccessor = (IHttpContextAccessor)requestServices.GetRequiredService(typeof(IHttpContextAccessor));
var actionContext = new ActionContext(httpContextAccessor.HttpContext, new RouteData(), new ActionDescriptor());
var tempDataProvider = requestServices.GetRequiredService(typeof(ITempDataProvider)) as ITempDataProvider;
using var outputStringWriter = new StringWriter();
var viewContext = new ViewContext(
actionContext,
view,
new ViewDataDictionary<TModel>(new EmptyModelMetadataProvider(), new ModelStateDictionary()) { Model = model },
new TempDataDictionary(actionContext.HttpContext, tempDataProvider),
outputStringWriter,
new HtmlHelperOptions());
await view.RenderAsync(viewContext);
return outputStringWriter.ToString();
}
}
}
In the controller
string str = await ViewToStringRenderer.RenderViewToStringAsync(HttpContext.RequestServices, $"~/Views/Emails/MyEmailTemplate.cshtml", new MyEmailModel { Prop1 = "Hello", Prop2 = 23 });
In ConfigureServices() in Startup.cs
services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
Here is how you do it in MVC 5
public static class ViewToStringRenderer
{
public static string RenderViewToString<TModel>(ControllerContext controllerContext, string viewName, TModel model)
{
ViewEngineResult viewEngineResult = ViewEngines.Engines.FindView(controllerContext, viewName, null);
if (viewEngineResult.View == null)
{
throw new Exception("Could not find the View file. Searched locations:\r\n" + viewEngineResult.SearchedLocations);
}
else
{
IView view = viewEngineResult.View;
using (var stringWriter = new StringWriter())
{
var viewContext = new ViewContext(controllerContext, view, new ViewDataDictionary<TModel>(model), new TempDataDictionary(), stringWriter);
view.Render(viewContext, stringWriter);
return stringWriter.ToString();
}
}
}
}
Then, from the controller
ViewToStringRenderer.RenderViewToString(this.ControllerContext, "~/Views/Emails/MyEmailTemplate.cshtml", model);
After you have the email content, it is easy to send the email using MailMessage and SmtpClient.
Email messages only understand two formats: plain text and HTML. Since Razor is neither, it will need to be processed by some engine, so that it gives you back the generated HTML.
That's exactly what happens when you use Razor in ASP.NET MVC, behind the scenes. The Razor file is compiled into a internal C# class, that gets executed, and the result of the execution is the string content of the HTML, that gets sent to the client.
Your problem is that you want and need that processing to run, only to get the HTML back as a string, instead of being sent to the browser. After that you can do whatever you want with the HTML string, including sending it as an e-mail.
There are several packages that include this power, and I've used Westwind.RazorHosting successfully, but you can also use RazorEngine with similar results. I would prefer RazorHosting for standalone non-web applications, and RazorEngine for web applications
Here is a (sanitized) version of some of my code - I'm using Westwind.RazorHosting to send razor-formatted emails from a windows service, using a strongly typed view.
RazorFolderHostContainer host = = new RazorFolderHostContainer();
host.ReferencedAssemblies.Add("NotificationsManagement.dll");
host.TemplatePath = templatePath;
host.Start();
string output = host.RenderTemplate(template.Filename, model);
MailMessage mm = new MailMessage { Subject = subject, IsBodyHtml = true };
mm.Body = output;
mm.To.Add(email);
var smtpClient = new SmtpClient();
await smtpClient.SendMailAsync(mm);
Have you took a look at MVC Mailer?
It's a free package available from GitHub (https://github.com/smsohan/MvcMailer)
There is a step by step guide for it too https://github.com/smsohan/MvcMailer/wiki/MvcMailer-Step-by-Step-Guide
It's also on Nuget too. https://www.nuget.org/packages/MvcMailer
Essentially it will parse your razor view into html.
Check out a razor processor like RazorEngine (https://razorengine.codeplex.com/) which is available on NuGet. It processes razor to create an output, which is what you'd then use as the body of your email.
The Mailzory project is a valuable and convenient choice for sending emails which have Razor templates.
// template path
var viewPath = Path.Combine("Views/Emails", "hello.cshtml");
// read the content of template and pass it to the Email constructor
var template = File.ReadAllText(viewPath);
var email = new Email(template);
// set ViewBag properties
email.ViewBag.Name = "Johnny";
email.ViewBag.Content = "Mailzory Is Funny";
// send email
var task = email.SendAsync("mailzory#outlook.com", "subject");
task.Wait()
this project is hosted at Github. Also there is a nuget package available for Mailzory.

Render View as String

Am trying to render a view as a string to be used as an email template. Am currently trying to implement this example:
https://weblog.west-wind.com/posts/2012/May/30/Rendering-ASPNET-MVC-Views-to-String
However am having difficulty with this section of code:
public ViewRenderer(ControllerContext controllerContext = null)
{
// Create a known controller from HttpContext if no context is passed
if (controllerContext == null)
{
if (HttpContext.Current != null)
controllerContext = CreateController<ErrorController>().ControllerContext;
else
throw new InvalidOperationException(
"ViewRenderer must run in the context of an ASP.NET " +
"Application and requires HttpContext.Current to be present.");
}
Context = controllerContext;
}
Visual Studio is giving me the following error:
"The type or namespace name 'ErrorController' could not be found (are you missing a using directive or an assembly reference?)"
Am probably missing something obvious but can't see what it is. Any ideas?
If you need to Render your view as a string, here is an extension method for the controller I wrote.
NB: I will try and find the exact link I used to help me with this, and update my answer when I find it.
Here is another link, describing this method.
This should do the trick:
public static string RenderViewToString(this Controller controller, string viewName, object model)
{
var context = controller.ControllerContext;
if (string.IsNullOrEmpty(viewName))
viewName = context.RouteData.GetRequiredString("action");
var viewData = new ViewDataDictionary(model);
using (var sw = new StringWriter())
{
var viewResult = ViewEngines.Engines.FindPartialView(context, viewName);
var viewContext = new ViewContext(context, viewResult.View, viewData, new TempDataDictionary(), sw);
viewResult.View.Render(viewContext, sw);
return sw.GetStringBuilder().ToString();
}
}
If you want to call this from a controller, you simply do the following:
var strView = this.RenderViewToString("YourViewName", yourModel);

Razor View Page as Email Template

I have designed an Email Template from Razor Syntax. When I send this template as Email using C# code and SMTP protocol, I get bare Razor and HTML markups as Email Body. Am I wrong in this approach? Are Razor Pages allowed as Email Template?
Here is my Page
#inherits ViewPage
#{
Layout = "_Layout";
ViewBag.Title = "";
}
<div class="container w-420 p-15 bg-white mt-40">
<div style="border-top:3px solid #22BCE5"> </div>
<span style="font-family:Arial;font-size:10pt">
Hello <b>{UserName}</b>,<br /><br />
Thanks for Registering to XYZ Portal<br /><br />
<a style="color:#22BCE5" href="{Url}">Click to Confirm Email</a><br />
<br /><br />
Thanks<br />
Admin (XYZ)
</span>
Update..
using (StreamReader reader = new StreamReader(HttpContext.Current.Server.MapPath("~/ContentPages/EmailConfTemplate.cshtml")))
{
body = reader.ReadToEnd();
//Replace UserName and Other variables available in body Stream
body = body.Replace("{UserName}", FirstName);
}
Later On I am replacing the SMTP Code as ..
MailMessage message = new MailMessage(
ApplicationWideData.fromEmailId, // From field
ToEmailId, // Recipient field
"Click On HyperLink To Verify Email Id", // Subject of the email message
body
);
You do not need any special libraries to render a Razor view to a string in an ASP.NET MVC application.
Here is how you do it in MVC Core 3
public static class ViewToStringRenderer
{
public static async Task<string> RenderViewToStringAsync<TModel>(IServiceProvider requestServices, string viewName, TModel model)
{
var viewEngine = requestServices.GetRequiredService(typeof(IRazorViewEngine)) as IRazorViewEngine;
ViewEngineResult viewEngineResult = viewEngine.GetView(null, viewName, false);
if (viewEngineResult.View == null)
{
throw new Exception("Could not find the View file. Searched locations:\r\n" + string.Join("\r\n", viewEngineResult.SearchedLocations));
}
else
{
IView view = viewEngineResult.View;
var httpContextAccessor = (IHttpContextAccessor)requestServices.GetRequiredService(typeof(IHttpContextAccessor));
var actionContext = new ActionContext(httpContextAccessor.HttpContext, new RouteData(), new ActionDescriptor());
var tempDataProvider = requestServices.GetRequiredService(typeof(ITempDataProvider)) as ITempDataProvider;
using var outputStringWriter = new StringWriter();
var viewContext = new ViewContext(
actionContext,
view,
new ViewDataDictionary<TModel>(new EmptyModelMetadataProvider(), new ModelStateDictionary()) { Model = model },
new TempDataDictionary(actionContext.HttpContext, tempDataProvider),
outputStringWriter,
new HtmlHelperOptions());
await view.RenderAsync(viewContext);
return outputStringWriter.ToString();
}
}
}
In the controller
string str = await ViewToStringRenderer.RenderViewToStringAsync(HttpContext.RequestServices, $"~/Views/Emails/MyEmailTemplate.cshtml", new MyEmailModel { Prop1 = "Hello", Prop2 = 23 });
In ConfigureServices() in Startup.cs
services.AddSingleton<IHttpContextAccessor, HttpContextAccessor>();
Here is how you do it in MVC 5
public static class ViewToStringRenderer
{
public static string RenderViewToString<TModel>(ControllerContext controllerContext, string viewName, TModel model)
{
ViewEngineResult viewEngineResult = ViewEngines.Engines.FindView(controllerContext, viewName, null);
if (viewEngineResult.View == null)
{
throw new Exception("Could not find the View file. Searched locations:\r\n" + viewEngineResult.SearchedLocations);
}
else
{
IView view = viewEngineResult.View;
using (var stringWriter = new StringWriter())
{
var viewContext = new ViewContext(controllerContext, view, new ViewDataDictionary<TModel>(model), new TempDataDictionary(), stringWriter);
view.Render(viewContext, stringWriter);
return stringWriter.ToString();
}
}
}
}
Then, from the controller
ViewToStringRenderer.RenderViewToString(this.ControllerContext, "~/Views/Emails/MyEmailTemplate.cshtml", model);
After you have the email content, it is easy to send the email using MailMessage and SmtpClient.
Email messages only understand two formats: plain text and HTML. Since Razor is neither, it will need to be processed by some engine, so that it gives you back the generated HTML.
That's exactly what happens when you use Razor in ASP.NET MVC, behind the scenes. The Razor file is compiled into a internal C# class, that gets executed, and the result of the execution is the string content of the HTML, that gets sent to the client.
Your problem is that you want and need that processing to run, only to get the HTML back as a string, instead of being sent to the browser. After that you can do whatever you want with the HTML string, including sending it as an e-mail.
There are several packages that include this power, and I've used Westwind.RazorHosting successfully, but you can also use RazorEngine with similar results. I would prefer RazorHosting for standalone non-web applications, and RazorEngine for web applications
Here is a (sanitized) version of some of my code - I'm using Westwind.RazorHosting to send razor-formatted emails from a windows service, using a strongly typed view.
RazorFolderHostContainer host = = new RazorFolderHostContainer();
host.ReferencedAssemblies.Add("NotificationsManagement.dll");
host.TemplatePath = templatePath;
host.Start();
string output = host.RenderTemplate(template.Filename, model);
MailMessage mm = new MailMessage { Subject = subject, IsBodyHtml = true };
mm.Body = output;
mm.To.Add(email);
var smtpClient = new SmtpClient();
await smtpClient.SendMailAsync(mm);
Have you took a look at MVC Mailer?
It's a free package available from GitHub (https://github.com/smsohan/MvcMailer)
There is a step by step guide for it too https://github.com/smsohan/MvcMailer/wiki/MvcMailer-Step-by-Step-Guide
It's also on Nuget too. https://www.nuget.org/packages/MvcMailer
Essentially it will parse your razor view into html.
Check out a razor processor like RazorEngine (https://razorengine.codeplex.com/) which is available on NuGet. It processes razor to create an output, which is what you'd then use as the body of your email.
The Mailzory project is a valuable and convenient choice for sending emails which have Razor templates.
// template path
var viewPath = Path.Combine("Views/Emails", "hello.cshtml");
// read the content of template and pass it to the Email constructor
var template = File.ReadAllText(viewPath);
var email = new Email(template);
// set ViewBag properties
email.ViewBag.Name = "Johnny";
email.ViewBag.Content = "Mailzory Is Funny";
// send email
var task = email.SendAsync("mailzory#outlook.com", "subject");
task.Wait()
this project is hosted at Github. Also there is a nuget package available for Mailzory.

Render Razor view to string in ASP.NET 5

In previous versions of ASP.NET it was possible, although not very simple, to render Razor views as strings. The methods I've seem are to use a fake controller, or also to use some external engine like RazorEngine.
Now, many things are changed with ASP.NET 5 and I was wondering whether or not this is now simpler than before. So in the new version of the framework is there one straightforward way to render Razor views as strings or we still need to use the methods from the previous versions?
I use the following types injected from the IServiceProvider:
ICompositeViewEngine viewEngine;
ITempDataProvider tempDataProvider;
IHttpContextAccessor httpContextAccessor;
I render the content using the following method:
private async Task<string> RenderView(string path, ViewDataDictionary viewDataDictionary, ActionContext actionContext)
{
using (var sw = new System.IO.StringWriter())
{
var viewResult = viewEngine.FindView(actionContext, path);
var viewContext = new ViewContext(actionContext, viewResult.View, viewDataDictionary, new TempDataDictionary(httpContextAccessor, tempDataProvider), sw);
await viewResult.View.RenderAsync(viewContext);
sw.Flush();
if (viewContext.ViewData != viewDataDictionary)
{
var keys = viewContext.ViewData.Keys.ToArray();
foreach (var key in keys)
{
viewDataDictionary[key] = viewContext.ViewData[key];
}
}
return sw.ToString();
}
}
I call it like this:
var path = "~/Views/Home/Index.cshtml";
var viewDataDictionary = new ViewDataDictionary(new Microsoft.AspNet.Mvc.ModelBinding.EmptyModelMetadataProvider(), new Microsoft.AspNet.Mvc.ModelBinding.ModelStateDictionary());
var actionContext = new ActionContext(httpContextAccessor.HttpContext, new Microsoft.AspNet.Routing.RouteData(), new ActionDescriptor());
viewDataDictionary.Model = null;
var text = await RenderView(path, viewDataDictionary, actionContext);
Of course, my viewDataDictionary and actionContext variables are set by another method for encapsulation. A modification to the new ViewDataDictionary line can result in a typed Model being bound to your View if you choose.
This code uses heavy usings, I think I've listed them below. Otherwise, VS2015 is pretty good about finding them.
using Microsoft.AspNet.Mvc;
using Microsoft.AspNet.Mvc.Rendering;
This was written under beta-3; it still builds, but some things may change. I'll try to come back here to update if it does.
There is a solution that I've used an year ago. I'm not sure if there is a new/better way to do, but it solves the problem.
public string RenderViewToString(string viewName, object model)
{
ViewData.Model = model;
using (var sw = new StringWriter())
{
var viewResult = ViewEngines.Engines.FindPartialView(ControllerContext, viewName);
var viewContext = new ViewContext(ControllerContext, viewResult.View, ViewData, TempData, sw);
viewResult.View.Render(viewContext, sw);
viewResult.ViewEngine.ReleaseView(ControllerContext, viewResult.View);
return sw.GetStringBuilder().ToString();
}
}

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