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docs: updated the documentation
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amyskippy committed Oct 6, 2024
1 parent 51a2a9e commit 79f7de2
Showing 1 changed file with 14 additions and 6 deletions.
20 changes: 14 additions & 6 deletions README.md
Original file line number Diff line number Diff line change
Expand Up @@ -36,14 +36,22 @@ public class MyClass

var dataReader = new SqlCommand("SELECT * FROM MyTable", connection).ExecuteReader();

List<MyClass> results = dataReader.To<MyClass>();
List<MyClass> results = dataReader.To<MyClass>(); // Generic method
// or
List<MyClass> results = dataReader.ToMyClass(); // Direct method
```

Some notes for the above

* The `ToMyClass()` method above - is an `IDataReader` extension method generated at compile time. You can even "go to definition" in Visual Studio and examine its code.
* The naming convention is `ToCLASSNAME()` we can't use generics here, since `<T>` is not part of method signatures in C# (considered in later versions of C#). If you find a prettier way - please contribute!
* Maps properies with public setters only.
* The `To<MyClass>()` method above - is an `IDataReader` extension method generated at compile time.
* The naming convention is `To<T>()` where `T` is your class name marked with `[GenerateDataReaderMapper]`, e.g. `MyClass`.
* Thanks to [@5andr0](https://github.com/5andr0) for the suggestion of how to add the generic version of this method.
* The `ToMyClass()` method is functionally identical to the `To<MyClass>()` method but maintained for backwards compatability.
* The naming convention is `ToCLASSNAME()`
* You can even "go to definition" in Visual Studio and examine the code for either of these two methods.
* Maps properties with public setters only.
* The datareader is being closed after mapping, so don't reuse it.
* Supports `enum` properties based on `int` and other implicit casting (sometimes a DataReader may decide to return `byte` for small integer database value, and it maps to `int` perfectly via some unboxing magic)
* Properly maps `DBNull` to `null`.
Expand Down Expand Up @@ -85,10 +93,10 @@ If you're already using the awesome [Dapper ORM](https://github.com/DapperLib/Da
public static List<T> Query<T>(this SqlConnection cn, string sql, object parameters = null)
{
if (typeof(T) == typeof(MyClass)) //our own class that we marked with attribute?
return cn.ExecuteReader(sql, parameters).ToMyClass() as List<T>; //use MapDataReader
return cn.ExecuteReader(sql, parameters).To<MyClass>() as List<T>; //use MapDataReader
if (typeof(T) == typeof(AnotherClass)) //another class we have enabled?
return cn.ExecuteReader(sql, parameters).ToAnotherClass() as List<T>; //again
return cn.ExecuteReader(sql, parameters).To<AnotherClass>() as List<T>; //again
//fallback to Dapper by default
return SqlMapper.Query<T>(cn, sql, parameters).AsList();
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