After Deploying to IIS, Swagger UI page is not displayed

Question

After deploying an ASP.NET Core Web API to IIS, Swagger UI page is not displayed.

Configure section:

app.UseSwaggerUI(c =>
        {
            if (env.IsDevelopment() || env.IsProduction())

            {
                c.SwaggerEndpoint("/swagger/v1/swagger.json", "My Test1 Api v1");
            }
        });

Configure service:

services.AddSwaggerGen( );

Answer 1

Add c.RoutePrefix = string.Empty;, will change the start page.

By default the url should be https://ip?port/swagger/index.html. And after you delpoyed this app, you will get 404 error, don't worry, you can append swagger in the url, it will show the index.html.

public void ConfigureServices(IServiceCollection services)
{
    services.AddControllers();
    ...
    services.AddSwaggerGen();
}

// This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
    ...
    app.UseSwagger();
    app.UseSwaggerUI(c =>
    {
        if (env.IsDevelopment() || env.IsProduction())

        {
            c.SwaggerEndpoint("/swagger/v1/swagger.json", "My Test1 Api v1");
            // Add this line, it will work for you
            c.RoutePrefix = string.Empty;
        }
    });

    app.UseHttpsRedirection();

    app.UseRouting();

    app.UseAuthorization();

    app.UseEndpoints(endpoints =>
    {
        endpoints.MapControllers();
    });
}