Using Dapper in C# MVVM and SQL Server 2019/Visual Studios Pro 2019 - dapper

Question

I am writing an application using C#, WPF, MVVM and SQL Server, and I am using Dapper as an ORM. Below is a snippet of the sample code I am trying to make work:
public List<MAKE THIS GENERIC> ExecuteSQLSPROC(string SPROCName, SqlParameter[] parameters, IEnumerable<MAKE THIS GENERIC> model)
{
using (IDbConnection connection = new System.Data.SqlClient.SqlConnection(DBHelper.CNNVal("MyDatabaseName")))
{
System.Data.SqlClient.SqlCommand command = new System.Data.SqlClient.SqlCommand();
command.Connection = (SqlConnection)connection;
command.CommandText = SPROCName;
DynamicParameters parms = new DynamicParameters();
for (int i = 0; i < parameters.Length; i++)
{
var parmname = parameters[i].ParameterName;
var parmvalue = parameters[i].Value;
// I KNOW I can put DIRECTION as a parameter variable but right now I don't want to!!
parms.Add(parmname, parmvalue);
}
var output = connection.Query<Make THIS GENERIC>(SPROCName, parms, commandType: CommandType.StoredProcedure).ToList();
return output; // return the recordset to the caller - a List<> of one object/model is acceptable - NOT POPULATING EXCEL spreadsheet with
// the results
}
}
I want to call this piece of code (which does not compile right now for obvious reasons) by supplying any ViewModel and be able to execute this code as if the ViewModel is generic within the routine. I need to know how to correctly code the above and also make the call to this routine with generic ViewModels (probably using a Lambda expression of some sort).
Basically, I want to be able to say "execute this SPROC, with these dynamic parameters and map the output to a ViewModel that is generic and return the results to the caller. Next time you're called it will be same logic, different SPROC, different parameters and ViewModel". I do NOT want extraneous comments that DO NOT directly answer this question. I know that I can add the parameter direction in a call the SQL SPROCs; but that knowledge is irrelevant to this question I am asking!

Answer 1

You can put your method in a generic class if you have other methods:
public class DbStuff<T>
{
public IList<T> ExecuteSQLSPROC(string SPROCName, SqlParameter[] parameters, IEnumerable<T> model)
{
using (IDbConnection connection = new System.Data.SqlClient.SqlConnection(DBHelper.CNNVal("MyDatabaseName")))
{
System.Data.SqlClient.SqlCommand command = new System.Data.SqlClient.SqlCommand();
command.Connection = (SqlConnection)connection;
command.CommandText = SPROCName;
DynamicParameters parms = new DynamicParameters();
for (int i = 0; i < parameters.Length; i++)
{
var parmname = parameters[i].ParameterName;
var parmvalue = parameters[i].Value;
// I KNOW I can put DIRECTION as a parameter variable but right now I don't want to!!
parms.Add(parmname, parmvalue);
}
var output = connection.Query<T>(SPROCName, parms, commandType: CommandType.StoredProcedure).ToList();
return output; // return the recordset to the caller - a List<> of one object/model is acceptable - NOT POPULATING EXCEL spreadsheet with
// the results
}
}
}
Then call it via:
var stuff = new DbStuff<MyViewModel>();
var results = stuff.ExecuteSQLSPROC("", blah, blah);
Or just make the method generic:
public IList<T> ExecuteSQLSPROC<T>(string SPROCName, SqlParameter[] parameters, IEnumerable<T> model)