Dapper Tutorial Dapper - Anonymous Result
Description
Extension methods can be used to execute a query and map the result using dynamic.
The anonymous result can be mapped from following extension methods:
These extension methods can be called from any object of type IDbConnection.
Example - Query
Query method can execute a query and map the result to a dynamic list.
string sql = "SELECT TOP 10 * FROM OrderDetails"; using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools())) { var orderDetails = connection.QueryFirstOrDefault(sql); FiddleHelper.WriteTable(orderDetails); }
Try it: .NET Core | .NET Framework
Example - QueryFirst
QueryFirst method can execute a query and map the first result to a dynamic list.
string sql = "SELECT * FROM OrderDetails WHERE OrderDetailID = @OrderDetailID;"; using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools())) { var orderDetail = connection.QueryFirst(sql, new {OrderDetailID = 1}); FiddleHelper.WriteTable(orderDetail); }
Try it: .NET Core | .NET Framework
Example - QueryFirstOrDefault
QueryFirstOrDefault method can execute a query and map the first result to a dynamic list, or a default value if the sequence contains no elements.
string sql = "SELECT * FROM OrderDetails WHERE OrderDetailID = @OrderDetailID;"; using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools())) { var orderDetail = connection.QueryFirstOrDefault(sql, new {OrderDetailID = 1}); FiddleHelper.WriteTable(orderDetail); }
Try it: .NET Core | .NET Framework
Example - QuerySingle
QuerySingle method can execute a query and map the first result to a dynamic list and throws an exception if there is not exactly one element in the sequence.
string sql = "SELECT * FROM OrderDetails WHERE OrderDetailID = @OrderDetailID;"; using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools())) { var orderDetail = connection.QuerySingle(sql, new {OrderDetailID = 1}); FiddleHelper.WriteTable(orderDetail); }
Try it: .NET Core | .NET Framework
Example - QuerySingleOrDefault
QuerySingleOrDefault method can execute a query and map the first result to a dynamic list, or a default value if the sequence is empty; this method throws an exception if there is more than one element in the sequence.
string sql = "SELECT * FROM OrderDetails WHERE OrderDetailID = @OrderDetailID;"; using (var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServerW3Schools())) { var orderDetail = connection.QuerySingleOrDefault(sql, new {OrderDetailID = 1}); FiddleHelper.WriteTable(orderDetail); }
Try it: .NET Core | .NET Framework