Skip to content

mgravell/fast-member

Repository files navigation

Fast access to .net fields/properties

In .NET reflection is slow... well, kinda slow. If you need access to the members of an arbitrary type, with the type and member-names known only at runtime - then it is frankly hard (especially for DLR types). This library makes such access easy and fast.

An introduction to the reasons behind fast-member can be found on my blog; example usage is simply:

var accessor = TypeAccessor.Create(type); 
string propName = // something known only at runtime 
while( /* some loop of data */ )
{ 
  accessor[obj, propName] = rowValue; 
}

or

// obj could be static or DLR 
var wrapped = ObjectAccessor.Create(obj);
string propName = // something known only at runtime 
Console.WriteLine(wrapped[propName]);

Ever needed an IDataReader?

This is pretty common if you are doing object-mapping between an object model and ADO.NET concepts such as DataTable or SqlBulkCopy; loading a DataTable (yes, some people still use it) from a sequence of typed objects can now be as easy as:

IEnumerable<SomeType> data = ... 
var table = new DataTable(); 
using(var reader = ObjectReader.Create(data)) 
{ 
  table.Load(reader); 
}

(the Create method offers parameters to control the specific members, if needed)

Or if you want to throw the data into a database as fast as humanly possible:

using(var bcp = new SqlBulkCopy(connection)) 
using(var reader = ObjectReader.Create(data, "Id", "Name", "Description")) 
{ 
  bcp.DestinationTableName = "SomeTable"; 
  bcp.WriteToServer(reader); 
}

Ahead of Time

Library emits IL code during runtime. Will not work in constrained Ahead of Time environments. Xamarin iOS and Unity IL2CPP are such.