Scribbles for my bad memory

Create a middleware to do that task

 public static void SetCurrentCulture(this IApplicationBuilder app)
 {
     app.Use(async (context, next) =>
     {
         var cultureQuery = context.Request.Headers["lang"] == "en" ? "en-US" : "zh-CN";
         if (!string.IsNullOrWhiteSpace(cultureQuery))
         {
             var culture = new CultureInfo(cultureQuery);
             CultureInfo.CurrentCulture = culture;
             CultureInfo.CurrentUICulture = culture;
         }
         await next();
     });
 }

Use the middleware in Startup.cs

 public void Configure(IApplicationBuilder app, IWebHostEnvironment env, ILog logger,
     IExceptionEntityService exceptionEntityService)
 {
     ...
     app.SetCurrentCulture();
     ...
 }