asp.net core输出中文乱码的问题

摘要

在学习asp.net core的时候，尝试在控制台，或者页面上输出中文，会出现乱码的问题。

问题重现

新建控制台和站点

    public class Program
    {
        public static void Main(string[] args)
        {           
            Console.WriteLine("您好，北京欢迎你");
            Console.Read();
        }
    }

站点

    public class Startup
    {
        // This method gets called by the runtime. Use this method to add services to the container.
        // For more information on how to configure your application, visit http://go.microsoft.com/fwlink/?LinkID=398940
        public void ConfigureServices(IServiceCollection services)
        {
        }

        // This method gets called by the runtime. Use this method to configure the HTTP request pipeline.
        public void Configure(IApplicationBuilder app, IHostingEnvironment env, ILoggerFactory loggerFactory)
        {
            loggerFactory.AddConsole();

            if (env.IsDevelopment())
            {
                app.UseDeveloperExceptionPage();
            }

            app.Run(async (context) =>
            {
                await context.Response.WriteAsync("您好，北京欢迎你");
            });
        }
    }

那么我们获取“GB2312”编码，然后对其编码呢？

        public static void Main(string[] args)
        {
            Console.WriteLine("您好，北京欢迎你");
            try
            {
                Console.WriteLine(Encoding.GetEncoding("GB2312"));
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            Console.Read();
        }
    }

'GB2312' is not a supported encoding name. For information on defining a custom encoding, see the documentation for the Encoding.RegisterProvider method.
Parameter name: name

上面的大概意思是Encoding 不支持GB2312编码，需要使用Encoding.RegisterProvider方法进行注册Provider。

            try
            {
                Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);
                Console.WriteLine(Encoding.GetEncoding("GB2312"));
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
            Console.Read();

CodePagesEncodingProvider在包System.Text.Encoding.CodePages中

      "System.Text.Encoding.CodePages/4.0.1": {
        "type": "package",
        "dependencies": {
          "Microsoft.NETCore.Platforms": "1.0.1",
          "System.Collections": "4.0.11",
          "System.Globalization": "4.0.11",
          "System.IO": "4.1.0",
          "System.Reflection": "4.1.0",
          "System.Resources.ResourceManager": "4.0.1",
          "System.Runtime": "4.1.0",
          "System.Runtime.Extensions": "4.1.0",
          "System.Runtime.Handles": "4.0.1",
          "System.Runtime.InteropServices": "4.1.0",
          "System.Text.Encoding": "4.0.11",
          "System.Threading": "4.0.11"
        },
        "compile": {
          "ref/netstandard1.3/System.Text.Encoding.CodePages.dll": {}
        },
        "runtimeTargets": {
          "runtimes/unix/lib/netstandard1.3/System.Text.Encoding.CodePages.dll": {
            "assetType": "runtime",
            "rid": "unix"
          },
          "runtimes/win/lib/netstandard1.3/System.Text.Encoding.CodePages.dll": {
            "assetType": "runtime",
            "rid": "win"
          }
        }
      },

好了，我们修改下代码，先注册，然后输出中文

    try
            {
                Encoding.RegisterProvider(CodePagesEncodingProvider.Instance);
                Console.WriteLine(Encoding.GetEncoding("GB2312"));
                Console.WriteLine("您好，北京欢迎你");
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }

结语

所以在页面上输出，或者在控制台输出中文的时候，要注意进行注册Provider。

参考

https://msdn.microsoft.com/zh-cn/library/system.text.encoding.registerprovider(v=vs.110).aspx