它非常简单，只需添加即可

 MultipleActiveResultSets=true; 

所以在web.config中以这种方式更改连接字符串：

 connectionString="Data Source=MATT-PCSQLEXPRESS;" + "Initial Catalog=Raise;Integrated Security=True;" + "MultipleActiveResultSets=true;" 

试试这个代码

必须参考这篇Msdn文章

  public static class ConfigurationService { static public string ConnectionString { get { try { // Specify the provider name, server and database. string providerName = "System.Data.SqlClient"; string serverName = @"192.168.1.106SQLEXPRESS"; string databaseName = "MyDatabaseName"; // Initialize the connection string builder for the // underlying provider. var sqlBuilder = new SqlConnectionStringBuilder(); // Set the properties for the data source. sqlBuilder.DataSource = serverName; sqlBuilder.InitialCatalog = databaseName; sqlBuilder.IntegratedSecurity = false; sqlBuilder.UserID = "Bob"; sqlBuilder.Password = "Bob1234"; sqlBuilder.MultipleActiveResultSets = true; sqlBuilder.ApplicationName = "EntityFramework"; // Build the SqlConnection connection string. string providerString = sqlBuilder.ToString(); // Initialize the EntityConnectionStringBuilder. var entityBuilder = new EntityConnectionStringBuilder(); //Set the provider name. entityBuilder.Provider = providerName; // Set the provider-specific connection string. entityBuilder.ProviderConnectionString = providerString; // Set the Metadata location. entityBuilder.Metadata = @"res://*/Models.MyDatabaseNameModel.csdl|res://*/Models.MyDatabaseNameModel.ssdl|res://*/Models.MyDatabaseNameModel.msl"; var result = entityBuilder.ToString(); return result; } catch (Exception) { } return string.Empty; } } } 

请注意， Models.MyDatabaseNameModel中的模型是VS项目的文件夹名称。

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