AspNetCore.Docs/aspnetcore/diagnostics/asp0015.md

title	description	author	monikerRange	ms.author	ms.date	uid
ASP0015: Suggest using IHeaderDictionary properties	Learn about analysis rule ASP0015: Suggest using IHeaderDictionary properties	tdykstra	>= aspnetcore-8.0	tdykstra	11/23/2022	diagnostics/asp0015

ASP0015: Suggest using IHeaderDictionary properties

	Value
Rule ID	ASP0015
Category	Usage
Fix is breaking or non-breaking	Non-breaking

Cause

IHeaderDictionary properties are the recommended strategy for accessing headers.

Rule description

IHeaderDictionary properties are recommended for accessing headers. Accessing headers using an indexer as in the example below is not recommended.

var app = WebApplication.Create();

app.MapGet("/", (HttpContext context) => context.Request.Headers[""content-type""]);

app.Run();

How to fix violations

To fix a violation of this rule, use the property specified in the analyzer message to access the header specified in the message or apply the associated codefix.

var app = WebApplication.Create();
app.MapGet("/", (HttpContext context) => context.Request.Headers.ContentType);
app.Run();

When to suppress warnings

Do not suppress a warning from this rule.