Asp.net identity 通过中间件管道对数据库进行种子设定会引发异常asp.net核心

我的解决方案中有3层。核心层、BLL层和DAL层。除了核心层（WebAPI层）之外，所有的都是类库。DAL层包含上下文、种子、迁移、实体和存储库类。我对核心层使用ASP.NET Core 3.0预览，对类库层使用.NET standard 2.0。seeder类中的Seed方法是异步的，用于返回任务。当核心项目运行时，出现以下异常：

当我删除.Wait方法调用时，没有抛出异常，API工作正常，但数据库没有种子

我该如何解决这个问题？谢谢

Startup.cs中间件管道：

播种机等级：

---

您可以尝试定义播种器类，如下所示：

public static class BlazeMartDbSeeder
{
    public static void Seed(UserManager<ApplicationUser> userMgr, RoleManager<IdentityRole> roleMgr)
    {
        //var user =  userMgr.FindByNameAsync("Raj");

        // Add User
        if (userMgr.FindByNameAsync("Raj").Result == null)
        {
            if (!( roleMgr.RoleExistsAsync("Manager").Result))
            {
                IdentityRole role = new IdentityRole();
                role.Name = "Manager";
                IdentityResult result = roleMgr.CreateAsync(role).Result;
                IdentityResult claim=roleMgr.AddClaimAsync(role, new Claim(type: "IsManager", value: "True")).Result;

                //  role.Claims.Add(new IdentityRoleClaim<string>() { ClaimType = "IsManager", ClaimValue = "True" });

            }

            ApplicationUser user = new ApplicationUser
            {
                UserName = "raj",
                FirstName = "Raj",
                LastName = "Narayanan",
                Email = "raj@raj.com"
            };

            IdentityResult userResult =  userMgr.CreateAsync(user, "Asp3raj#").Result;
            IdentityResult roleResult =  userMgr.AddToRoleAsync(user, "Manager").Result;
            IdentityResult claimResult =  userMgr.AddClaimAsync(user, new Claim("GreenBadge", "True")).Result;

            if (!userResult.Succeeded || !roleResult.Succeeded || !claimResult.Succeeded)
            {
                throw new InvalidOperationException("Failed to build user and roles");
            }
        }

        //user =  userMgr.FindByNameAsync("Shawnw");

        // Add User
        if (userMgr.FindByNameAsync("Shawnw").Result == null)
        {
            if (!(roleMgr.RoleExistsAsync("Employee").Result))
            {
                IdentityRole role = new IdentityRole();
                role.Name = "Employee";
                IdentityResult result=roleMgr.CreateAsync(role).Result;
                IdentityResult claim =roleMgr.AddClaimAsync(role, new Claim(type: "IsEmployee", value: "True")).Result;

                //  role.Claims.Add(new IdentityRoleClaim<string>() { ClaimType = "IsManager", ClaimValue = "True" });

            }

            ApplicationUser user = new ApplicationUser
            {
                UserName = "shawnw",
                FirstName = "Shawn",
                LastName = "Wildermuth",
                Email = "shawnw@s.com"
            };

            IdentityResult userResult = userMgr.CreateAsync(user, "P@ssw0rd!").Result;
            IdentityResult roleResult = userMgr.AddToRoleAsync(user, "Employee").Result;
            IdentityResult claimResult = userMgr.AddClaimAsync(user, new Claim("OrangeBadge", "True")).Result;

            if (!userResult.Succeeded || !roleResult.Succeeded || !claimResult.Succeeded)
            {
                throw new InvalidOperationException("Failed to build user and roles");
            }
        }

        // user =  userMgr.FindByNameAsync("John");

        // Add User
        if (userMgr.FindByNameAsync("John").Result == null)
        {
            if (!(roleMgr.RoleExistsAsync("Vendor").Result))
            {
                IdentityRole role = new IdentityRole();
                role.Name = "Vendor";
                IdentityResult result = roleMgr.CreateAsync(role).Result;
                IdentityResult claim= roleMgr.AddClaimAsync(role, new Claim(type: "IsVendor", value: "True")).Result;

                //  role.Claims.Add(new IdentityRoleClaim<string>() { ClaimType = "IsManager", ClaimValue = "True" });

            }

            ApplicationUser user = new ApplicationUser
            {
                UserName = "johng",
                FirstName = "John",
                LastName = "Galli",
                Email = "gali@gali.com"
            };

            IdentityResult userResult = userMgr.CreateAsync(user, "P@ssw0rd!").Result;
            IdentityResult roleResult = userMgr.AddToRoleAsync(user, "Vendor").Result;
            IdentityResult claimResult = userMgr.AddClaimAsync(user, new Claim("BlueBadge", "True")).Result;

            if (!userResult.Succeeded || !roleResult.Succeeded || !claimResult.Succeeded)
            {
                throw new InvalidOperationException("Failed to build user and roles");
            }
        }

    }
}

Startup.cs

public void Configure(IApplicationBuilder app, IWebHostEnvironment env, UserManager<ApplicationUser> userMgr, RoleManager<IdentityRole> roleMgr)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }

        BlazeMartDbSeeder.Seed(userMgr, roleMgr);

        app.UseHttpsRedirection();

        app.UseRouting();

        app.UseAuthorization();

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

注意：密码的组成部分包括大小写字母、数字和特殊符号

---

关于ASP.NET核心标识中的种子用户和角色数据，您可以参考。

这很有效。谢谢我需要指出的是，我在这一行打错了：role.Name=ManEmployeeager；。它应该是员工而不是员工经理。它抛出了一个异常，但在我纠正了错误后，一切都正常了。我编辑了你的答案以反映这一更正。

public static class BlazeMartDbSeeder
{
    public static void Seed(UserManager<ApplicationUser> userMgr, RoleManager<IdentityRole> roleMgr)
    {
        //var user =  userMgr.FindByNameAsync("Raj");

        // Add User
        if (userMgr.FindByNameAsync("Raj").Result == null)
        {
            if (!( roleMgr.RoleExistsAsync("Manager").Result))
            {
                IdentityRole role = new IdentityRole();
                role.Name = "Manager";
                IdentityResult result = roleMgr.CreateAsync(role).Result;
                IdentityResult claim=roleMgr.AddClaimAsync(role, new Claim(type: "IsManager", value: "True")).Result;

                //  role.Claims.Add(new IdentityRoleClaim<string>() { ClaimType = "IsManager", ClaimValue = "True" });

            }

            ApplicationUser user = new ApplicationUser
            {
                UserName = "raj",
                FirstName = "Raj",
                LastName = "Narayanan",
                Email = "raj@raj.com"
            };

            IdentityResult userResult =  userMgr.CreateAsync(user, "Asp3raj#").Result;
            IdentityResult roleResult =  userMgr.AddToRoleAsync(user, "Manager").Result;
            IdentityResult claimResult =  userMgr.AddClaimAsync(user, new Claim("GreenBadge", "True")).Result;

            if (!userResult.Succeeded || !roleResult.Succeeded || !claimResult.Succeeded)
            {
                throw new InvalidOperationException("Failed to build user and roles");
            }
        }

        //user =  userMgr.FindByNameAsync("Shawnw");

        // Add User
        if (userMgr.FindByNameAsync("Shawnw").Result == null)
        {
            if (!(roleMgr.RoleExistsAsync("Employee").Result))
            {
                IdentityRole role = new IdentityRole();
                role.Name = "Employee";
                IdentityResult result=roleMgr.CreateAsync(role).Result;
                IdentityResult claim =roleMgr.AddClaimAsync(role, new Claim(type: "IsEmployee", value: "True")).Result;

                //  role.Claims.Add(new IdentityRoleClaim<string>() { ClaimType = "IsManager", ClaimValue = "True" });

            }

            ApplicationUser user = new ApplicationUser
            {
                UserName = "shawnw",
                FirstName = "Shawn",
                LastName = "Wildermuth",
                Email = "shawnw@s.com"
            };

            IdentityResult userResult = userMgr.CreateAsync(user, "P@ssw0rd!").Result;
            IdentityResult roleResult = userMgr.AddToRoleAsync(user, "Employee").Result;
            IdentityResult claimResult = userMgr.AddClaimAsync(user, new Claim("OrangeBadge", "True")).Result;

            if (!userResult.Succeeded || !roleResult.Succeeded || !claimResult.Succeeded)
            {
                throw new InvalidOperationException("Failed to build user and roles");
            }
        }

        // user =  userMgr.FindByNameAsync("John");

        // Add User
        if (userMgr.FindByNameAsync("John").Result == null)
        {
            if (!(roleMgr.RoleExistsAsync("Vendor").Result))
            {
                IdentityRole role = new IdentityRole();
                role.Name = "Vendor";
                IdentityResult result = roleMgr.CreateAsync(role).Result;
                IdentityResult claim= roleMgr.AddClaimAsync(role, new Claim(type: "IsVendor", value: "True")).Result;

                //  role.Claims.Add(new IdentityRoleClaim<string>() { ClaimType = "IsManager", ClaimValue = "True" });

            }

            ApplicationUser user = new ApplicationUser
            {
                UserName = "johng",
                FirstName = "John",
                LastName = "Galli",
                Email = "gali@gali.com"
            };

            IdentityResult userResult = userMgr.CreateAsync(user, "P@ssw0rd!").Result;
            IdentityResult roleResult = userMgr.AddToRoleAsync(user, "Vendor").Result;
            IdentityResult claimResult = userMgr.AddClaimAsync(user, new Claim("BlueBadge", "True")).Result;

            if (!userResult.Succeeded || !roleResult.Succeeded || !claimResult.Succeeded)
            {
                throw new InvalidOperationException("Failed to build user and roles");
            }
        }

    }
}

public void Configure(IApplicationBuilder app, IWebHostEnvironment env, UserManager<ApplicationUser> userMgr, RoleManager<IdentityRole> roleMgr)
    {
        if (env.IsDevelopment())
        {
            app.UseDeveloperExceptionPage();
        }

        BlazeMartDbSeeder.Seed(userMgr, roleMgr);

        app.UseHttpsRedirection();

        app.UseRouting();

        app.UseAuthorization();

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