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Good practice for DeploymentItem?

I'm fairly rusty when it comes to C#. I've been poking my nose around internet trying to find a solution to my question without success.
I created a test project using MSTest. Some tests use files, that I added to my project test under the folder TestData, and they are copied when executing the test by using the attribute DeploymentItem.
Example: [DeploymentItem(#"TestData\test.txt")]
This copies test.txt at the execution folder and it works. However, when I want to use this file in the test, I then have to work on "test.txt" instead of #"TestData\test.txt". Thus, if I want to factorize my code, I have to have two variables:
const string testFileName = "test.txt";
const string testFilePath = #"TestData\test.txt";
and then use them as
[DeploymentItem(testFilePath)]
public void TestFunction()
{
[...]testFileName[...]
}
Ideally, I want instead to write:
[DeploymentItem(testFilePath)]
public void TestFunction()
{
[...]testFilePath[...]
}
This way I would only need one variable.
It would work if I use the second argument of DeploymentItem as such:
const string testFilesFolder = "TestData";
const string testFilePath = #"TestData\test.txt";
[DeploymentItem(testFilePath, testFilesFolder)]
public void TestFunction()
{
[...]testFilePath[...]
}
However, that forces me and everyone to think about passing the second argument every time we use DeploymentItem. But it has the merit of working.
Here are the different things I tried to do to address the issue:
Inheriting from DeploymentItem to simply add my own constructor: DeploymentItem is sealed so this is not possible.
Creating my own attribute, by copying the code of DeploymentItem. The file is not copied at all:
[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method, AllowMultiple = true)]
class DeployFileAttribute : Attribute
{
public DeployFileAttribute(string path)
{
Path = path;
OutputDirectory = System.IO.Path.GetDirectoryName(path);
}
public string Path { get; }
public string OutputDirectory { get; }
}
[DeployFile(testFilePath)] // testFilePath is not copied at all, even though the constructor is correctly executed.
Creating a method that would return the attribute. It does not seem like it is possible to use the result of a method as an attribute:
public static DeploymentItemAttribute DeployFile(string path)
{
return new DeploymentItemAttribute(path, System.IO.Path.GetDirectoryName(path));
} // No compilation error
[DeployFile(testFilePath)] // DeployFileAttribute type does not exist
Creating something like a C++ style using statement or C style macro, I can't seem to find a syntax that works
using DeployFile(string toto) = DeploymentItemAttribute(toto, System.IO.Path.GetDirectoryName(path)); // Syntax is wrong, could not find one that works
Any hindsight would be welcome!

From my point of view, there are only two possibilities:
You use DeploymentItem in the way it was created by Microsoft.
[DeploymentItem(testFilePath, testFilesFolder)] as you manshioned in your post
You can combine source path:
const string testFileName = "test.txt";
[DeploymentItem(#"TestData\" + testFileName)]
public void TestFunction()
{
[...]testFileName[...]
}
In this case, you'll have just one variable :)
You can write your own extension for MSTest and create an attribute you need. But this is not the easy way. As key words for this approach, you could google for TestExtensionExecution, ITestMethodInvoker and TestClassExtensionAttribute
On the other hand, this is very understandable, why DeploymentItem is implemented as it is. Do not forget, that the source folder can be an absolute path as well. So assume, that you have the following attribute [DeploymentItem(#"S:\Shared\TestFiles\AAA\BBB\test.txt")] What should be the destination folder? But even with relative paths: [DeploymentItem(#"..\..\..\TestFiles\AAA\BBB\test.txt")] - can say the name of the destination folder in this case?

C# programmatically edit my .NET assembly at runtime

I have a .NET assembly that is built by me but would like to be able rewrite the .DLL with some minor but arbitrary attribute change file at runtime. Specifically I would like to be able to change a property of an attribute of a class so that I can customize the binary depending on the situation.
To illustrate, I want to achieve the effect of editing the assembly being generated from the code
[SomeAttribute("Name")]
public class MyClass{
...
such that the new assembly is functionally the same as
[SomeAttribute("Custom Name")]
public class MyClass{
...
And this "Custom Name" could be anything (determined at runtime). Is this possible to do at runtime?
The reason why the actual .DLL needs to be modified is because it will get loaded up by a seperate process which cannot determine the runtime information (I do not control this process).
Experimentation so far has shown that it seems to work if the new "Custom Name" is the same length as the original, but not otherwise (even if you edit the preceding byte that specifies the length; presumably there are offsets stored in the file somewhere).
EDIT: Forgot to mention, solution needs to be under the .NET 2 framework as well.

Unclear what you really want to do (XY problem?)
Still, if you want to modify an assembly, you normally use Mono.Cecil that self-describes as: you can load existing managed assemblies, browse all the contained types, modify them on the fly and save back to the disk the modified assembly. .
Note that an attribute can contain extra data on top of the data that is passed as a parameter:
public class MyAttribute : Attribute
{
public MyAttribute(string str)
{
argument = str;
}
private string argument;
public string Argument { get; }
public string AssemblyName
{
get
{
return Assembly.GetEntryAssembly().FullName;
}
}
}
[MyAttribute("Hello")]
class Program
{
static void Main(string[] args)
{
var attr = typeof(Program).GetCustomAttribute<MyAttribute>();
Console.WriteLine(attr.Argument);
Console.WriteLine(attr.AssemblyName);
}
}

Using the extremely helpful suggestion from #xanatos I have made this solution:
Under .NET 2, you can install package Mono.Cecil 0.9.6.1.
The code then is as follows:
AssemblyDefinition assbDef = AssemblyDefinition.ReadAssembly("x.dll");
TypeDefinition type = assbDef.MainModule.GetType("NameSpace.MyClass").Resolve();
foreach (CustomAttribute attr in type.CustomAttributes)
{
TypeReference argTypeRef = null;
int? index = null;
for (int i = 0; i < attr.ConstructorArguments.Count; i++)
{
CustomAttributeArgument arg = attr.ConstructorArguments[i];
string stringValue = arg.Value as string;
if (stringValue == "Name")
{
argTypeRef = arg.Type;
index = i;
}
}
if (index != null)
{
attr.ConstructorArguments[(int)index] = new CustomAttributeArgument(argTypeRef, newName);
}
}
assbDef.Write("y.dll");
Which will search an assembly for any attribute arguments with value "Name" and replace their value with newName.

Rather than modifying the DLL, you can add attributes at run-time using the TypeDescriptor class; e.g.
TypeDescriptor.AddAttributes(typeof(MyClass), new SomeAttribute("Custom Name"));
The only caveat with this approach is that code which relies purely on reflection will not be able to read the added attribute(s) - you must use TypeDescriptor.GetAttributes(). However, most of the built-in .NET Framework methods that operate on attributes are aware of metadata added at run-time.
https://msdn.microsoft.com/en-us/library/system.componentmodel.typedescriptor_methods(v=vs.110).aspx

Get all #Html.GetResource() in a .cshtml file?

We have a resource file called Resouce.NL.resx. This file contains translations for a specific language. However, alot of the #Html.GetResource() arguments dont yet exists inside the resource file.
I now have to loop through every .cshtml file to manually add all those resources.
Is there any tool or extionsion to get all #Html.GetResource() inside .cshtml files that dont yet exists within a resource file?

You can get all resources as a dictionary using System.Resources.ResourceManager in C#.
Example:
var resorces =new System.Resources.ResourceManager("YourNamespace.YourResourceFileName", Assembly.GetExecutingAssembly())
.GetResourceSet(System.Threading.Thread.CurrentThread.CurrentCulture, true, true)
.OfType<DictionaryEntry>();
Razor: You can create and use custom helper.example:
Helper:
public static class MyClass{
public static string ResourceFor<T>(this HtmlHelper html, object key) {
return new System.Resources.ResourceManager(typeof(T)).GetString(key.ToString());
}
}
Use:
#Html.ResourceFor<MyProject.Resouce.NL>("Test") //where `MyProject.Resouce.NL` is your resource namespace with class name

BundleTransformer.Less inject variables depending on context/request

We would like the use the bundling mechanism of System.Web.Optimization in combination with the Less transformer.
The problem is that the same application/server serves pages for different branded websites. So depending on the 'SiteContext' the same .less files are used but different values should be used by the .less variables. So we want the (re)use the same less files but with different variables depending on the context of the request.
I tried a couple of different theories:
In all 3 cases I setup different bundles depending on the SiteContext.
1 inject an #import directive with the themed variables by using a custom VirtualPathProvider that intercepts the variables.less file.
So I have:
the styling file eg: header.less (imports the variables file)
the variables file: variables.less
a themed variables file: variables-theme.less (injected in variables.less via the VirtualPathProvider)
This is not working because the BundleTransformer cache sees this as the same file and doesn't know about the SiteContext. The cache key is based on the Url of the IAsset and we cannot influence this behavior.
2 Replace the variables.less import by variables-themed.less with an custom transformer that runs before the Less transformer.
Again no luck, same caching issues.
And as a side effect, the extra transformer was not called in debug because the assets are not bundled but called individually by the LessAssetHandler. This could be solved by writing your own AssetHandler that calls all required transformers.
3 create themed Asset names that are resolved by a custom VirtualPathProvider
Eg. Add header-themeX.less to the bundle, this file doesn't exist but you resolve this file to header.less and use method 2 to set the correct variables file import. (replace the import of the variables.less to the themed version).
Once again no luck. I think this could solve the caching issue if it wasn't for the Bundle.Include(string virtualPath) that does a File.Exists(path) internally. It doesn't pass via the CustomVirtualPathProvider.
Am I looking to deep to solve this?
All ideas are welcome, I can imagine that this will become a problem to more and more people as the System.Web.Optimization library gets more popular...
Keep in mind that:
we have a lot of .less/css files
we will have 5 or so themes
we like to keep things working in visual studio (that is why header.less has a ref. to variables.less)
Thanks for any feedback.

Michael!
You use the Microsoft ASP.NET Web Optimization Framework and the Bundle Transformer in multi-tenant environment, so you need to replace some components of the System.Web.Optimization and create own versions of the debugging HTTP-handlers (see «Problem: LESS file imports are added to BundleResponse.Files collection» discussion). As far as I know, Murat Cakir solve all these problems in the SmartStore.NET project.
In the Bundle Transformer there are 2 ways to inject of LESS-variables:
Look a properties GlobalVariables and ModifyVariables of LESS-translator:
using System.Collections.Generic;
using System.Web.Optimization;
using BundleTransformer.Core.Builders;
using BundleTransformer.Core.Orderers;
using BundleTransformer.Core.Transformers;
using BundleTransformer.Core.Translators;
using BundleTransformer.Less.Translators;
public class BundleConfig
{
public static void RegisterBundles(BundleCollection bundles)
{
var nullBuilder = new NullBuilder();
var nullOrderer = new NullOrderer();
var lessTranslator = new LessTranslator
{
GlobalVariables = "my-variable='Hurrah!'",
ModifyVariables = "font-family-base='Comic Sans MS';body-bg=lime;font-size-h1=50px"
};
var cssTransformer = new CssTransformer(new List<ITranslator>{ lessTranslator });
var commonStylesBundle = new Bundle("~/Bundles/BootstrapStyles");
commonStylesBundle.Include(
"~/Content/less/bootstrap-3.1.1/bootstrap.less");
commonStylesBundle.Builder = nullBuilder;
commonStylesBundle.Transforms.Add(cssTransformer);
commonStylesBundle.Orderer = nullOrderer;
bundles.Add(commonStylesBundle);
}
}
Create a custom item transformation:
using System.Text;
using System.Web.Optimization;
public sealed class InjectContentItemTransform : IItemTransform
{
private readonly string _beforeContent;
private readonly string _afterContent;
public InjectContentItemTransform(string beforeContent, string afterContent)
{
_beforeContent = beforeContent ?? string.Empty;
_afterContent = afterContent ?? string.Empty;
}
public string Process(string includedVirtualPath, string input)
{
if (_beforeContent.Length == 0 && _afterContent.Length == 0)
{
return input;
}
var contentBuilder = new StringBuilder();
if (_beforeContent.Length > 0)
{
contentBuilder.AppendLine(_beforeContent);
}
contentBuilder.AppendLine(input);
if (_afterContent.Length > 0)
{
contentBuilder.AppendLine(_afterContent);
}
return contentBuilder.ToString();
}
}
And register this transformation as follows:
using System.Web.Optimization;
using BundleTransformer.Core.Orderers;
using BundleTransformer.Core.Bundles;
public class BundleConfig
{
public static void RegisterBundles(BundleCollection bundles)
{
var nullOrderer = new NullOrderer();
const string beforeLessCodeToInject = #"#my-variable: 'Hurrah!';";
const string afterLessCodeToInject = #"#font-family-base: 'Comic Sans MS';
#body-bg: lime;
#font-size-h1: 50px;";
var commonStylesBundle = new CustomStyleBundle("~/Bundles/BootstrapStyles");
commonStylesBundle.Include(
"~/Content/less/bootstrap-3.1.1/bootstrap.less",
new InjectContentItemTransform(beforeLessCodeToInject, afterLessCodeToInject));
commonStylesBundle.Orderer = nullOrderer;
bundles.Add(commonStylesBundle);
}
}
Both ways have disadvantage: the injection of LESS-variables does not work in debug mode.

MvvmCross ViewTypeResolver doesn't resolve Tag (fragment or custom type)

Actual situation is, that I added to the MvxViewTypeResolver class the "Fragment"-Case, so it does look like this:
#region Copyright
// <copyright file="MvxViewTypeResolver.cs" company="Cirrious">
// (c) Copyright Cirrious. http://www.cirrious.com
// This source is subject to the Microsoft Public License (Ms-PL)
// Please see license.txt on http://opensource.org/licenses/ms-pl.html
// All other rights reserved.
// </copyright>
//
// Project Lead - Stuart Lodge, Cirrious. http://www.cirrious.com
#endregion
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Android.Views;
using Cirrious.MvvmCross.Binding.Android.Interfaces.Binders;
namespace Cirrious.MvvmCross.Binding.Android.Binders
{
public class MvxViewTypeResolver : IMvxViewTypeResolver
{
private Dictionary<string, Type> _cache = new Dictionary<string, Type>();
public IDictionary<string, string> ViewNamespaceAbbreviations { get; set; }
#region IMvxViewTypeResolver Members
public virtual Type Resolve(string tagName)
{
Type toReturn;
if (_cache.TryGetValue(tagName, out toReturn))
return toReturn;
var unabbreviatedTagName = UnabbreviateTagName(tagName);
var longLowerCaseName = GetLookupName(unabbreviatedTagName);
var viewType = typeof(View);
#warning AppDomain.CurrentDomain.GetAssemblies is only the loaded assemblies - so we might miss controls if not already loaded
var query = from assembly in AppDomain.CurrentDomain.GetAssemblies()
from type in assembly.GetTypes()
where viewType.IsAssignableFrom(type)
where (type.FullName ?? "-").ToLowerInvariant() == longLowerCaseName
select type;
toReturn = query.FirstOrDefault();
_cache[tagName] = toReturn;
return toReturn;
}
private string UnabbreviateTagName(string tagName)
{
var filteredTagName = tagName;
if (ViewNamespaceAbbreviations != null)
{
var split = tagName.Split(new char[] {'.'}, 2, StringSplitOptions.RemoveEmptyEntries);
if (split.Length == 2)
{
var abbreviate = split[0];
string fullName;
if (ViewNamespaceAbbreviations.TryGetValue(abbreviate, out fullName))
{
filteredTagName = fullName + "." + split[1];
}
}
}
return filteredTagName;
}
#endregion
protected string GetLookupName(string tagName)
{
var nameBuilder = new StringBuilder();
switch (tagName)
{
case "View":
case "ViewGroup":
nameBuilder.Append("android.view.");
break;
case "fragment":
nameBuilder.Append("android.app.");
break;
default:
if (!IsFullyQualified(tagName))
nameBuilder.Append("android.widget.");
break;
}
nameBuilder.Append(tagName);
return nameBuilder.ToString().ToLowerInvariant();
}
private static bool IsFullyQualified(string tagName)
{
return tagName.Contains(".");
}
}
}
Now it is submitting the correct longLowerCaseTagName (android.app.fragment) but in the query it isn't able to resolve the type.
My suggestion is, that the fragment-control isn't loaded when the type should be resolved. Maybe there is an other way to get the type resolved?
Also if I add a custom type (giving the tag Mvx.MyCustomType in the axml) it doesn't get resolved. Do I have to add something in the MvxBindingAttributes.xml in this case?
Thanks for the help!

First an explanation of the code:
The custom XML inflater factory used by the MvvmCross Binder tries to load Views in a very similar way to the standard 2.x Android XML inflater.
The default code for the view type resolution is indeed in: https://github.com/slodge/MvvmCross/blob/master/Cirrious/Cirrious.MvvmCross.Binding/Android/Binders/MvxViewTypeResolver.cs
If your xml contains a name such as <MyCompany.MyProject.MyViews.MyFirstView /> then the view type resolver:
first checks for abbreviations and expands these into full namespaces - by default the only known abbreviation is Mvx. which is expanded to: Cirrious.MvvmCross.Binding.Android.Views.. If you want to add more abbrevations then override ViewNamespaceAbbreviations in https://github.com/slodge/MvvmCross/blob/master/Cirrious/Cirrious.MvvmCross.Binding/Android/MvxBaseAndroidBindingSetup.cs
then checks to see if the unabbreviated name is a non-namespaced name. If it is, then it assumes that the class is the Android namespace and prepends it with android.view. or android.widget.
then converts the fully namespaced name to all lowercase as a case-insensitive lookup key
uses that lowercase key to search all Types which derive from View in all loaded assemblies.
caches the result (whether its null or not) in order to speed up subsequent inflations.
All of this behaviour was designed to match the default Android xml view inflation code in http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/2.3.6_r1/android/view/LayoutInflater.java#LayoutInflater.createViewFromTag%28java.lang.String%2Candroid.util.AttributeSet%29
With that explanation out of the way - here's an answer to your questions:
MvvmCross does not yet currently contain any Fragment support. The official MonoDroid fragment support itself was only released last week, and I've not yet had anybody request fragments - Android "fragmentation" seems to have kept most people back on Activity and Dialog based code.
Briefly ;ooking at the documentation, fragment isn't an Android View - it looks like Fragment inherits directly from Java.Lang.Object - see http://developer.android.com/reference/android/app/Fragment.html
Because of this, there's no way that the MvvmCross ViewTypeResolver will currently work with fragments.
I would suggest that if you need both mvvmcross and fragments today, then your best bet is to replace the default resolver (using IoC) with your own resolver - but I can't offer much advice on this as I haven't yet fully read and understood the droid docs on http://developer.android.com/guide/topics/fundamentals/fragments.html
From my experience in creating the current inflation code, then I think you will find the source essential reading when you do this - e.g. see : http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/4.0.1_r1/android/view/LayoutInflater.java#LayoutInflater.createViewFromTag%28android.view.View%2Cjava.lang.String%2Candroid.util.AttributeSet%29
I can't give you any information on when official mvvmcross fragment support will be available - it's not something that is currently scheduled.
Custom views are supported, but will not normally live in the Mvx. abbreviated namespace.
They are much more likely to live in your UI application namespace, or in some shared library.
To see a custom view in action, see the PullToRefresh example in the tutorial - https://github.com/slodge/MvvmCross/blob/master/Sample%20-%20Tutorial/Tutorial/Tutorial.UI.Droid/Resources/Layout/Page_PullToRefreshView.axml