UWP 尝试通过 EFCore 连接到 SQL Server Express 时出错
Error on UWP trying to connect to SQL Server Express via EFCore
团队，
这真让我抓狂。我在启动 UWP 应用程序时总是收到此错误：
Microsoft.Data.SqlClient.SqlException: 'A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Shared Memory Provider, error: 40 - Could not open a connection to SQL Server)'
内部异常：
Microsoft.Data.SqlClient.SqlException
HResult=0x80131904
Message=A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Shared Memory Provider, error: 40 - Could not open a connection to SQL Server)
Source=Core Microsoft SqlClient Data Provider
StackTrace:
at Microsoft.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, SqlCredential credential, Object providerInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString userConnectionOptions, SessionData reconnectSessionData, Boolean applyTransientFaultHandling, String accessToken, DbConnectionPool pool, SqlAuthenticationProviderManager sqlAuthProviderManager)
at Microsoft.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection, DbConnectionOptions userOptions)
at Microsoft.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnectionPool pool, DbConnection owningObject, DbConnectionOptions options, DbConnectionPoolKey poolKey, DbConnectionOptions userOptions)
at Microsoft.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)
at Microsoft.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection)
at Microsoft.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal& connection)
at Microsoft.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection)
at Microsoft.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection)
at Microsoft.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource1 retry, DbConnectionOptions userOptions)
at Microsoft.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource1 retry, DbConnectionOptions userOptions)
at Microsoft.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource1 retry)
at Microsoft.Data.SqlClient.SqlConnection.Open()
at Microsoft.EntityFrameworkCore.Storage.RelationalConnection.OpenDbConnection(Boolean errorsExpected)
at Microsoft.EntityFrameworkCore.Storage.RelationalConnection.Open(Boolean errorsExpected)
at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.ExecuteReader(RelationalCommandParameterObject parameterObject)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryingEnumerable1.Enumerator.InitializeReader(DbContext _, Boolean result)
at Microsoft.EntityFrameworkCore.SqlServer.Storage.Internal.SqlServerExecutionStrategy.Execute[TState,TResult](TState state, Func3 operation, Func3 verifySucceeded)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryingEnumerable1.Enumerator.MoveNext()
at System.Collections.Generic.List1.AddEnumerable(IEnumerable1 enumerable)
at System.Collections.Generic.List1..ctor(IEnumerable1 collection)
at System.Linq.Enumerable.ToList[TSource](IEnumerable1 source)
at UWP_EF_i9.MainPage.Page_Loaded(Object sender, RoutedEventArgs e) in E:\Users\Massimo\OneDrive\Development\Source\UWP EF i9\UWP EF i9\MainPage.xaml.cs:line 35
内部异常 1：
Win32Exception: 访问被拒绝
由于 UWP 中的 EFCore 无法 dbscaffold 数据库，按照此处找到的建议，我做了一个 EF.Core WPF 应用程序，搭建了数据库，创建了 类... 导入了生成的 类 在 UWP 应用程序中（在适用的情况下重命名命名空间）。
在 UWP 应用程序中，我添加了 Microsoft.EntityFrameworkCore 和 Microsoft.EntityFrameworkCore.SQLServer 并添加了企业功能：企业身份验证
所以一切都应该没问题...但是...它不起作用。在 WPF 中运行良好的完全相同的 LINQ 查询在 UWP
中给出了错误
有什么想法吗？我错过了什么？
--- 编辑 1
我什至添加了此页面中的代码：
Use a SQL Server database in a UWP app
connectionString = "Data Source=YourServerName\SQLEXPRESS;Initial Catalog=NORTHWIND;Integrated Security=SSPI";
所以对我来说：
try
{
using (SqlConnection conn = new SqlConnection((App.Current as App).ConnectionString))
{
conn.Open();
if (conn.State == System.Data.ConnectionState.Open)
{
using (SqlCommand cmd = conn.CreateCommand())
{
cmd.CommandText = "Select * from tAPP";
using (SqlDataReader reader = cmd.ExecuteReader())
{
while (reader.Read())
{
}
}
}
}
}
}
但是 conn.Open() 失败并显示相同的消息
默认情况下，UWP 应用没有网络访问权限。参见：
Capabilities
In order to use networking, you must add appropriate
capability elements to your app manifest. If no network capability is
specified in your app's manifest, your app will have no networking
capability, and any attempt to connect to the network will fail.
我发现了问题:(
在这里解释：
Use a SQL Server database in a UWP app
在以下部分：无法连接到您的数据库？
TCP/IP 协议默认禁用，必须启用。
现在 WPF 中的同一个应用程序怎么可能工作，VS2019 能够连接（更不用说 SSMS 了……）而只有 UWP 不连接对我来说是个谜……但现在它可以工作了！
团队， 这真让我抓狂。我在启动 UWP 应用程序时总是收到此错误：
Microsoft.Data.SqlClient.SqlException: 'A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Shared Memory Provider, error: 40 - Could not open a connection to SQL Server)'
内部异常：
Microsoft.Data.SqlClient.SqlException HResult=0x80131904 Message=A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: Shared Memory Provider, error: 40 - Could not open a connection to SQL Server) Source=Core Microsoft SqlClient Data Provider StackTrace: at Microsoft.Data.SqlClient.SqlInternalConnectionTds..ctor(DbConnectionPoolIdentity identity, SqlConnectionString connectionOptions, SqlCredential credential, Object providerInfo, String newPassword, SecureString newSecurePassword, Boolean redirectedUserInstance, SqlConnectionString userConnectionOptions, SessionData reconnectSessionData, Boolean applyTransientFaultHandling, String accessToken, DbConnectionPool pool, SqlAuthenticationProviderManager sqlAuthProviderManager) at Microsoft.Data.SqlClient.SqlConnectionFactory.CreateConnection(DbConnectionOptions options, DbConnectionPoolKey poolKey, Object poolGroupProviderInfo, DbConnectionPool pool, DbConnection owningConnection, DbConnectionOptions userOptions) at Microsoft.Data.ProviderBase.DbConnectionFactory.CreatePooledConnection(DbConnectionPool pool, DbConnection owningObject, DbConnectionOptions options, DbConnectionPoolKey poolKey, DbConnectionOptions userOptions) at Microsoft.Data.ProviderBase.DbConnectionPool.CreateObject(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection) at Microsoft.Data.ProviderBase.DbConnectionPool.UserCreateRequest(DbConnection owningObject, DbConnectionOptions userOptions, DbConnectionInternal oldConnection) at Microsoft.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, UInt32 waitForMultipleObjectsTimeout, Boolean allowCreate, Boolean onlyOneCheckConnection, DbConnectionOptions userOptions, DbConnectionInternal& connection) at Microsoft.Data.ProviderBase.DbConnectionPool.TryGetConnection(DbConnection owningObject, TaskCompletionSource
1 retry, DbConnectionOptions userOptions, DbConnectionInternal& connection) at Microsoft.Data.ProviderBase.DbConnectionFactory.TryGetConnection(DbConnection owningConnection, TaskCompletionSource1 retry, DbConnectionOptions userOptions, DbConnectionInternal oldConnection, DbConnectionInternal& connection) at Microsoft.Data.ProviderBase.DbConnectionInternal.TryOpenConnectionInternal(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource1 retry, DbConnectionOptions userOptions) at Microsoft.Data.ProviderBase.DbConnectionClosed.TryOpenConnection(DbConnection outerConnection, DbConnectionFactory connectionFactory, TaskCompletionSource1 retry, DbConnectionOptions userOptions) at Microsoft.Data.SqlClient.SqlConnection.TryOpen(TaskCompletionSource1 retry) at Microsoft.Data.SqlClient.SqlConnection.Open() at Microsoft.EntityFrameworkCore.Storage.RelationalConnection.OpenDbConnection(Boolean errorsExpected) at Microsoft.EntityFrameworkCore.Storage.RelationalConnection.Open(Boolean errorsExpected) at Microsoft.EntityFrameworkCore.Storage.RelationalCommand.ExecuteReader(RelationalCommandParameterObject parameterObject) at Microsoft.EntityFrameworkCore.Query.Internal.QueryingEnumerable1.Enumerator.InitializeReader(DbContext _, Boolean result) at Microsoft.EntityFrameworkCore.SqlServer.Storage.Internal.SqlServerExecutionStrategy.Execute[TState,TResult](TState state, Func3 operation, Func3 verifySucceeded) at Microsoft.EntityFrameworkCore.Query.Internal.QueryingEnumerable1.Enumerator.MoveNext() at System.Collections.Generic.List1.AddEnumerable(IEnumerable1 enumerable) at System.Collections.Generic.List1..ctor(IEnumerable1 collection) at System.Linq.Enumerable.ToList[TSource](IEnumerable1 source) at UWP_EF_i9.MainPage.Page_Loaded(Object sender, RoutedEventArgs e) in E:\Users\Massimo\OneDrive\Development\Source\UWP EF i9\UWP EF i9\MainPage.xaml.cs:line 35
内部异常 1： Win32Exception: 访问被拒绝
由于 UWP 中的 EFCore 无法 dbscaffold 数据库，按照此处找到的建议，我做了一个 EF.Core WPF 应用程序，搭建了数据库，创建了 类... 导入了生成的 类 在 UWP 应用程序中（在适用的情况下重命名命名空间）。
在 UWP 应用程序中，我添加了 Microsoft.EntityFrameworkCore 和 Microsoft.EntityFrameworkCore.SQLServer 并添加了企业功能：企业身份验证
所以一切都应该没问题...但是...它不起作用。在 WPF 中运行良好的完全相同的 LINQ 查询在 UWP
中给出了错误有什么想法吗？我错过了什么？
--- 编辑 1
我什至添加了此页面中的代码：
Use a SQL Server database in a UWP app connectionString = "Data Source=YourServerName\SQLEXPRESS;Initial Catalog=NORTHWIND;Integrated Security=SSPI";
所以对我来说：
try
{
using (SqlConnection conn = new SqlConnection((App.Current as App).ConnectionString))
{
conn.Open();
if (conn.State == System.Data.ConnectionState.Open)
{
using (SqlCommand cmd = conn.CreateCommand())
{
cmd.CommandText = "Select * from tAPP";
using (SqlDataReader reader = cmd.ExecuteReader())
{
while (reader.Read())
{
}
}
}
}
}
}
但是 conn.Open() 失败并显示相同的消息
默认情况下，UWP 应用没有网络访问权限。参见：
Capabilities
In order to use networking, you must add appropriate capability elements to your app manifest. If no network capability is specified in your app's manifest, your app will have no networking capability, and any attempt to connect to the network will fail.
我发现了问题:( 在这里解释： Use a SQL Server database in a UWP app
在以下部分：无法连接到您的数据库？
TCP/IP 协议默认禁用，必须启用。 现在 WPF 中的同一个应用程序怎么可能工作，VS2019 能够连接（更不用说 SSMS 了……）而只有 UWP 不连接对我来说是个谜……但现在它可以工作了！