I have this class, in which I am wrapping dapper calls in order to do something like
var results = SqlWrapper.ExecuteQuery<Product,Customer>("SELECT id FROM Products; SELECT id FROM Customers;");
Where
results[0] = List<Product>
results[1] = List<Customer>
I support 1,2,3 output objects, but would like arbitrary. The class is also ugly and full of copy and pasted code. I account for if I want to reuse a connection by optionally passing a connection but the code just seems unclean. What I would really like is a way to define params T[]
but as I understand that doesnt work. Is this any way this code can be cleaned/shortened?
using System.Collections.Generic;
using System.Data.SqlClient;
using System.Linq;
using Dapper;
namespace SqlWrapper
{
public static class SqlWrapper
{
private const string SqlConnectionString = "Server=localhost;Database=TTDS;User Id=sa;Password=sa;";
public static List<T> ExecuteQuery<T>(string sql, object param = null, SqlConnection sqlConnection = null)
{
if (sqlConnection != null)
{
return sqlConnection.Query<T>(sql, param).ToList();
}
using (var tempSqlConnection = new SqlConnection(SqlConnectionString))
{
tempSqlConnection.Open();
return tempSqlConnection.Query<T>(sql, param).ToList();
}
}
public static List<dynamic> ExecuteQuery<T1, T2>(string sql, object param = null, SqlConnection sqlConnection = null)
{
if (sqlConnection != null)
{
return MultiQuery<T1, T2>(sqlConnection, sql, param);
}
using (var tempSqlConnection = new SqlConnection(SqlConnectionString))
{
return MultiQuery<T1, T2>(tempSqlConnection, sql, param);
}
}
public static List<dynamic> ExecuteQuery<T1, T2, T3>(string sql, object param = null,
SqlConnection sqlConnection = null)
{
if (sqlConnection != null)
{
return MultiQuery<T1, T2, T3>(sqlConnection, sql, param);
}
using (var tempSqlConnection = new SqlConnection(SqlConnectionString))
{
return MultiQuery<T1, T2, T3>(tempSqlConnection, sql, param);
}
}
private static List<dynamic> MultiQuery<T1, T2>(SqlConnection sqlConnection, string sql, object param = null)
{
var rv = new List<dynamic>();
using (var grid = sqlConnection.QueryMultiple(sql, param))
{
rv.Add(grid.Read<T1>().ToList());
rv.Add(grid.Read<T2>().ToList());
}
return rv;
}
private static List<dynamic> MultiQuery<T1, T2, T3>(SqlConnection sqlConnection, string sql, object param = null)
{
var rv = new List<dynamic>();
using (var grid = sqlConnection.QueryMultiple(sql, param))
{
rv.Add(grid.Read<T1>().ToList());
rv.Add(grid.Read<T2>().ToList());
rv.Add(grid.Read<T3>().ToList());
}
return rv;
}
public static void ExecuteNonQuery(SqlConnection sqlConnection, string sql, object param, int? timeout = null)
{
if (sqlConnection != null)
{
sqlConnection.Execute(sql, param, commandTimeout: timeout);
}
else
{
using (var tempSqlConnection = new SqlConnection(SqlConnectionString))
{
tempSqlConnection.Open();
tempSqlConnection.Execute(sql, param, commandTimeout: timeout);
}
}
}
}
}
Here is some untested code that demonstrates a couple of ideas that I had.
Tuple<List<T>,List<U>,List<V>>
you can have strongly typed return values that you can easily usepublic static class SqlWrapper
{
private const string SqlConnectionString = "Server=localhost;Database=TTDS;User Id=sa;Password=sa;";
private class NoResult { }
public static List<T1> ExecuteQuery<T1>(string sql, object param = null, SqlConnection sqlConnection = null)
{
return ExecuteQuery<T1, NoResult, NoResult>(sql, param, sqlConnection).Item1;
}
public static Tuple<List<T1>, List<T2>> ExecuteQuery<T1, T2>(string sql, object param = null, SqlConnection sqlConnection = null)
{
var result = ExecuteQuery<T1, T2, NoResult>(sql, param, sqlConnection);
return Tuple.Create(result.Item1, result.Item2);
}
public static Tuple<List<T1>, List<T2>, List<T3>> ExecuteQuery<T1, T2, T3>(string sql, object param = null, SqlConnection sqlConnection = null)
{
List<T1> list1;
List<T2> list2 = null;
List<T3> list3 = null;
bool needsDisposed = false;
if (sqlConnection == null)
{
sqlConnection = new SqlConnection(SqlConnectionString);
sqlConnection.Open();
needsDisposed = true;
}
try
{
using (var grid = sqlConnection.QueryMultiple(sql, param))
{
list1 = grid.Read<T1>().ToList();
if (typeof(T2) != typeof(NoResult))
{
list2 = grid.Read<T2>().ToList();
}
if (typeof(T3) != typeof(NoResult))
{
list3 = grid.Read<T3>().ToList();
}
return Tuple.Create(list1, list2, list3);
}
}
finally { if (needsDisposed) sqlConnection.Dispose(); }
}
public static void ExecuteNonQuery(SqlConnection sqlConnection, string sql, object param, int? timeout = null)
{
bool needsDisposed = false;
if (sqlConnection == null)
{
sqlConnection = new SqlConnection(SqlConnectionString);
sqlConnection.Open();
needsDisposed = true;
}
try { sqlConnection.Execute(sql, param, commandTimeout: timeout); }
finally { if (needsDisposed) sqlConnection.Dispose(); }
}
}