aspnet-core-model-binding

Containing the Alias model binder and Delimiting Query String Value Provider

Package	Version
AliasModelBinder Client
AliasModelBinder Web
DelimitingQueryStringValueProvider Web

Alias Model Binder

A model binder for ASP.NET Core. Use multiple alternative property names in your query strings.

For example, you can use this:

api/controller/action?SomePropertyName=1&SomePropertyName=2 ,

api/controller/action?SomeOtherThing=1&SomeOtherThing=2 and

api/controller/action?s=1&s=2

at the same time.

Why might you want to do this?

• Perhaps you've changed your request model property names and want to keep backward compatibility?
• Perhaps you're trying to reduce query string length by using shortened property names.

How do you add this to your project?

Add the web package to your web project.

Then add an attribute to your request class

public class SomeRequest
{
	[BindingAlias("n")]   // btw, this would be an awful property name. Thank goodness for the modelbinder
	public int[] SomeNumbers{ get; set; }
}

and configure your aspnetcore project to use the model binder in Startup.cs

public void ConfigureServices(IServiceCollection services)
{
        services
            .AddMvc()
            .AddMvcOptions(options =>
            {
                AliasModelBinderProvider.Configure(options.ModelBinderProviders);
            });
}

Now you can use both your original query api/controller/action?someNumbers=1&someNumbers=2&someNumbers=3&someNumbers=4&someNumbers=5as well as api/controller/action?n=1&n=2&n=3&n=4&n=5.

Optionally, if you want to define attributes in your client project, you can take the client package, which contains just the attribute definitions and has no dependencies. If you're happy to (re)define your objects with the attributes in your web project, you don't need this package.

Look at the AliasModelBinder.ExampleApp in the test/ folder to see a full example of an application using alias model binding.

Delimiting Query String Value Provider

A Value Provider for ASP.NET Core. Pass less verbose arrays in your query strings.

We've seen queries that look like this: api/controller/action?number=1&number=2&number=3&number=4&number=5. But wouldn't it be simpler if we used the Delimiting Query String Provider to write something like this instead:

api/controller/action?number=1,2,3,5

Why would you want to do this?

• Shorter query strings
• You find this syntax clearer

How do you add this to your project?

Add the web package to your web project.

Then just configure your aspnet core to use it in Startup.cs

public void ConfigureServices(IServiceCollection services)
{
        services
            .AddMvc()
            .AddMvcOptions(options =>
            {
                DelimitingQueryStringValueProviderFactory.Configure(options.ValueProviderFactories);
            });
}

There's an extra argument to pass a custom choice of delimiter. "," is the default.

I could have passed "_" and had query strings like api/controller/action?number=1_2_3 for example.

Now you can use this alternative syntax for all the collections in your query strings.

Look at the DelimitingQueryStringValueProvider.ExampleApp in the test/ folder to see a full example of an application using alias model binding.

compatiblity

All web packages have a dependancy on Microsoft.AspNetCore.Mvc.Core version 2.2.5 (not the abstractions package Microsoft.AspNetCore.Mvc.Abstractions), and so are only compatible with web projects using a version of Microsoft.AspNetCore.Mvc.Core that's binary compatible with 2.2.5.

Client packages have no dependancies.