Aspnetcore: Console.WriteLine produces strange text in Blazor 0.8.0

Created on 30 Jan 2019 · 6Comments · Source: dotnet/aspnetcore

Repro steps:

dotnet new -i Microsoft.AspNetCore.Blazor.Templates::0.8.0-preview-19075-0444
dotnet new blazor -o BlazorApp1
Edit Program.cs to add Console.WriteLine("Hello, world!"); in Program.Main

Expected result:

Browser dev console shows: "Hello, world!"

Actual result:

WASM: mono_pe_file_map: Error opening file mscorlib.dll (3): No such file or directorymono_pe_file_map: Error opening file Mono.WebAssembly.Interop.dll (3): No such file or directorymono_pe_file_map: Error opening file Microsoft.JSInterop.dll (3): No such file or directorymono_pe_file_map: Error opening file BlazorApp1.dll (3): No such file or directorymono_pe_file_map: Error opening file Microsoft.AspNetCore.Blazor.dll (3): No such file or directorymono_pe_file_map: Error opening file Microsoft.Extensions.DependencyInjection.Abstractions.dll (3): No such file or directoryHello, world

area-blazor

Source

danroth27

Most helpful comment

@tezine Console.WriteLine will only write to the browser console when you're running client-side in the browser. For a Razor Components app Console.WriteLine will write to the console on the server.

For anyone who doesn't know, you can see the server console in the Output window in Visual Studio, just select 'ASP.NET Core Web Server in the select list:

tomRedox on 25 May 2019

👍3 😄1

All 6 comments

@SteveSandersonMS @lewing

danroth27 on 30 Jan 2019

I think this was a temporary logging regression in mono right around the hash you pulled. See https://github.com/mono/mono/pull/12588

lewing on 30 Jan 2019

In my case, Console.WriteLine simply doesn't write anything. I can hit a breakpoint while debugging razor components, but nothing is displayed in chrome console.

tezine on 11 Feb 2019

@tezine Console.WriteLine will only write to the browser console when you're running client-side in the browser. For a Razor Components app Console.WriteLine will write to the console on the server.

danroth27 on 11 Feb 2019

@tezine Console.WriteLine will only write to the browser console when you're running client-side in the browser. For a Razor Components app Console.WriteLine will write to the console on the server.

For anyone who doesn't know, you can see the server console in the Output window in Visual Studio, just select 'ASP.NET Core Web Server in the select list:

tomRedox on 25 May 2019

👍3 😄1

@tezine Console.WriteLine will only write to the browser console when you're running client-side in the browser. For a Razor Components app Console.WriteLine will write to the console on the server.

For anyone who doesn't know, you can see the server console in the Output window in Visual Studio, just select 'ASP.NET Core Web Server in the select list:

So many thanks for that... I was stuck on Debug log... 😄