Network Programming in .NET

Templating is extremely common, and is used to separate the data (often in JSON) from the presentation layer, which can either be on the client side (Mustache, Angular, Vue, React) , or on the server side (ASP.NET, Razor, etc.)

The template is typically hard-coded so that the data changes, but the template used to render that data in a presentable way is fixed. However, in certain circumstances, you may want to offer the ability to the user to change the template.

This could be in a situation where you want to offer full flexibility in presentation to the end-customer. Perhaps you want them to be able to style their own webpage, user portal, or report, or pdf. In this case, allowing both a dynamic template applied to dynamic data can offer much more flexibility.

This approach demonstrates the use of Razor, which is used commonly in modern .NET web apps, although it requires a very technical user, and could potentially cause some security issues, if the end user were to inject malicious code into the template.

So, without further Ado, let’s take a look at this project.

First, I’ll define some data as follows;

{
  "Company": "Microsoft",
  "Directors": [
    "Bill Gates",
    "Steve Ballmer"
  ]
}

Which I save as data.json, and set the property to “Copy always” in Visual Studio.

Then I define a template like so;

@Model.Company, has @Model.Directors.Count directors which are: @foreach (var Director in Model.Directors) { @String.Concat(Director," ") }

Which is designed to read “Microsoft has 2 directors which are Bill Gates Steve Ballmer”, this would be saved as “template.html” in the project.

Now, I Install the relevant NuGet packages, and usings;

using Newtonsoft.Json.Linq;  // Install-Package Newtonsoft.JSON
using RazorEngine; // Install-Package RazorEngine.NetCore
using RazorEngine.Templating;

And finally, put it all together as follows;

var data = File.ReadAllText("data.json");
var template = File.ReadAllText("template.html");
dynamic model = JObject.Parse(data);
var result =
Engine.Razor.RunCompile(
    template,
    "template",
    null,
    (object)model);
Console.WriteLine(result);

Viola!

The github repo for this project is available here: https://github.com/infiniteloopltd/RazorTemplating