C# Coding Standard – Position of Attribute in relation to Target

attributesccoding-standardscoding-style

I had thought that this was one of the few solved problems in C# coding standards / style; Attributes always appear on the line above the thing to which they are applied a la

[SomeClassAttribute]
class SomeClass
{
   [SomeFieldAttribute]
   bool someField;

   [SomeEnumAttribute]
   SomeEnum
   { 
     SomeValue
   }

   [SomeMethodAttribute]
   void SomeMethod() 
   { 
   }
}

But recently I've started to see Attributes in-line with the thing to which they are applied:

[SomeClassAttribute] class SomeClass
{
   [SomeFieldAttribute] bool someField;

   [SomeEnumAttribute] SomeEnum
   { 
     SomeValue
   }

   [SomeMethodAttribute] void SomeMethod() 
   { 
   }
}

For example on the Microsoft website and in the FileHelpers open source project. Is this just laziness on the part of the author of example code, or something that people actually use on a day to day basis, and if so why?

Best Answer

You can't put the attribute on the line above if it's being applied to a parameter.

e.g. this example from an ASP.NET MVC book

public ViewResult List([DefaultValue(1)] int page)
{
    // ... 
}

Maybe this has led to some people choosing to write attributes inline?

Also another example involving LINQ to SQL mappings..

[Column] public string Name { get; set; }
[Column] public string Description { get; set; }
[Column] public decimal Price { get; set; }
[Column] public string Category { get; set; }

The [Column] attribute almost feels like another modifier like the public access or the type, I can see how it might feel comfortable to write it inline like that.

Related Solutions

ASP.NET MVC Structure – Correct Way to Implement .NET MVC Website Structure

Based upon the limited description so far, the best answer I can give is "maybe."

Here's my partial take on MVC, which generally aligns with others' takes. But there's always bones of contention to be had. I would recommend Martin Fowler's articles as a good starting point with MVC and the other MVx variants.

The View should not be aware of the Model; it only knows what the Controller feeds it.
The Controller is more than welcome to directly pass a data structure from the Model to the View. But the Controller is on the hook to maintain that contract with the View if the Model should change.

In other words, the Controller may retrieve a List of users from the Model and then pass that List directly to the View. In this case, the structures magically aligned and all three layers are able to utilize the same (or similar) structure.

Should the View need additional details later on, then the Controller will be responsible for accessing the Model as necessary in order to provide those additional details back to the View.

C# – In ASP.NET MVC/Razor, how to add initializer JavaScript to a “control”

I'm not entirely sure I've identified the right problem, but if I have, this may help:

We created a class called ScriptManager which lets us add arbitrary javascript files and/or functions to the bottom of all our pages when they are rendered. Give this a try:

public class ScriptManager
{
    public List<string> scripts = new List<string>();
    public List<string> scriptFiles = new List<string>();
}
public static class HtmlExtensions
{

    [ThreadStatic]
    private static ControllerBase pageDataController;
    [ThreadStatic]
    private static ScriptManager pageData;

    public static ScriptManager ScriptManager(this HtmlHelper html)
    {
        ControllerBase controller = html.ViewContext.Controller;

        // This makes sure we get the top-most controller
        while (controller.ControllerContext.IsChildAction)
        {
            controller = controller.ControllerContext.ParentActionViewContext.Controller;
        }
        if (pageDataController == controller)
        {
            // We've been here before
            return pageData;
        }
        else
        {
            // Initial setup
            pageDataController = controller;
            pageData = new ScriptManager();
            return pageData;
        }
    }
}

Then, at the bottom of your _Layout.cshtml page:

@foreach (var script in Html.ScriptManager().scriptFiles.Distinct())
{
    @Html.Script(script);
}
@foreach (var script in Html.ScriptManager().scripts)
{
    @Html.Raw("<script type='text/javascript'>")
    @Html.Raw(script)
    @Html.Raw("</script>")
}

Finally, you use it in a partial view like:

@{
  Html.ScriptManager().scriptFiles.Add(Url.Content("~/Scripts/jquery.blockUI.js"));
 }

You lose the ability to tell the client about the scripts in the header of the page, but they will be included on all pages you use a partial view that uses the blockUI (for example).

Best Answer

Related Solutions

ASP.NET MVC Structure – Correct Way to Implement .NET MVC Website Structure

C# – In ASP.NET MVC/Razor, how to add initializer JavaScript to a “control”

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