IdentityServer4的介绍将不再叙述，百度下可以找到，且官网的快速入门例子也有翻译的版本。这里主要从Client应用场景方面介绍对IdentityServer4的应用，资料主要来源于官网。
二、Client应用场景介绍
Client类是为OpenID Connect或OAuth 2.0 协议建模的。
我们先看官网快速入门中给的Client例子
public static IEnumerable<Client> GetClients() { // client credentials client return new List<Client> { new Client { ClientId = "Client", AllowedGrantTypes = GrantTypes.ClientCredentials, ClientSecrets = { new Secret("secret".Sha256()) }, AllowedScopes = { "api1" } }, // resource owner password grant client new Client { ClientId = "ro.client", AllowedGrantTypes = GrantTypes.ResourceOwnerPassword, ClientSecrets = { new Secret("secret".Sha256()) }, AllowedScopes = { "api1" } }, // OpenID Connect hybrid flow and client credentials client (MVC) new Client { ClientId = "mvc", ClientName = "MVC Client", AllowedGrantTypes = GrantTypes.HybridAndClientCredentials, ClientSecrets = { new Secret("secret".Sha256()) }, RedirectUris = { ":5002/signin-oidc" }, PostLogoutRedirectUris = { ":5002/signout-callback-oidc" }, AllowedScopes = { IdentityServerConstants.StandardScopes.OpenId, IdentityServerConstants.StandardScopes.Profile, "api1" }, AllowOfflineAccess = true }, // JavaScript Client new Client { ClientId = "js", ClientName = "JavaScript Client", AllowedGrantTypes = GrantTypes.Implicit, AllowAccessTokensViaBrowser = true, RedirectUris = { ":5003/callback.html" }, PostLogoutRedirectUris = { ":5003/index.html" }, AllowedCorsOrigins = { ":5003" }, AllowedScopes = { IdentityServerConstants.StandardScopes.OpenId, IdentityServerConstants.StandardScopes.Profile, "api1" }, } }; }