UseWhen works instead of Mapwhen

[ashishonce]

regarding this line

app.MapWhen(
        context => context.Request.Path.ToString().EndsWith(".report"),
        appBranch => {
            // ... optionally add more middleware to this branch
            appBranch.UseMyHandler();
        });

while creating a list of multiple middlewares. app.MapWhen is not forwarding the request to further pipeline, instead app.UseWhen is working properly

Edit by @Rick-Anderson
2.5K PV

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Document Details

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• ID: 60f81f11-5621-b581-69f5-60093946b8ed
• Version Independent ID: 886858c7-29eb-714a-22ff-c30973d889e1
• Content: Migrate HTTP handlers and modules to ASP.NET Core middleware
• Content Source: aspnetcore/migration/http-modules.md
• Product: aspnet-core
• GitHub Login: @Rick-Anderson
• Microsoft Alias: tdykstra

[Rick-Anderson]

@mperdeck please review

[Rick-Anderson]

Have @Tratcher review after .NET 8 RTW

• app.MapWhen creates a new branch in the middleware pipeline, and only middleware registered on the new branch is executed if the predicate passed to app.MapWhen returns true. Middleware registered on the main branch isn't executed.
• app.UseWhen doesn't create a new branch in the middleware pipeline. All middleware registered after app.UseWhen is executed, regardless of whether the predicate passed to app.UseWhen returns true or false.