Auto Mapper : how to map Expressions - asp.net-mvc-5

Question

public IEnumerable<CustomBo> FindBy(Expression<Func<CustomBo, bool>> predicate)
{
Mapper.CreateMap<Expression<Func<CustomBo, bool>>, Expression<Func<Entity, bool>>>();
var newPredicate = Mapper.Map<Expression<Func<Entity, bool>>>(predicate);
IQueryable<Entity> query = dbSet.Where(newPredicate);
Mapper.CreateMap<Entity,CustomBo>();
var searchResult = Mapper.Map<List<CustomBo>>(query);
return searchResult;
}
I want to map customBo type to Entity Type..
Here customBo is my model and Entity is Database entity from edmx.
I'm using AutoMapper.
I'm Getting following Error
Could not find type map from destination type Data.Customer to source type Model.CustomerBO. Use CreateMap to create a map from the source to destination types.
Could not find type map from destination type Data.Customer to source type Model.CustomerBO. Use CreateMap to create a map from the source to destination types.
Any Suggession what I'm missiong here..
Thanks

Answer 1

I find a work around. I create my custom methods to map Expression.
public static class MappingHelper
{
public static Expression<Func<TTo, bool>> ConvertExpression<TFrom, TTo>(this Expression<Func<TFrom, bool>> expr)
{
Dictionary<Expression, Expression> substitutues = new Dictionary<Expression, Expression>();
var oldParam = expr.Parameters[0];
var newParam = Expression.Parameter(typeof(TTo), oldParam.Name);
substitutues.Add(oldParam, newParam);
Expression body = ConvertNode(expr.Body, substitutues);
return Expression.Lambda<Func<TTo, bool>>(body, newParam);
}
static Expression ConvertNode(Expression node, IDictionary<Expression, Expression> subst)
{
if (node == null) return null;
if (subst.ContainsKey(node)) return subst[node];
switch (node.NodeType)
{
case ExpressionType.Constant:
return node;
case ExpressionType.MemberAccess:
{
var me = (MemberExpression)node;
var newNode = ConvertNode(me.Expression, subst);
MemberInfo info = null;
foreach (MemberInfo mi in newNode.Type.GetMembers())
{
if (mi.MemberType == MemberTypes.Property)
{
if (mi.Name.ToLower().Contains(me.Member.Name.ToLower()))
{
info = mi;
break;
}
}
}
return Expression.MakeMemberAccess(newNode, info);
}
case ExpressionType.AndAlso:
case ExpressionType.OrElse:
case ExpressionType.LessThan:
case ExpressionType.LessThanOrEqual:
case ExpressionType.GreaterThan:
case ExpressionType.GreaterThanOrEqual:
case ExpressionType.Equal: /* will probably work for a range of common binary-expressions */
{
var be = (BinaryExpression)node;
return Expression.MakeBinary(be.NodeType, ConvertNode(be.Left, subst), ConvertNode(be.Right, subst), be.IsLiftedToNull, be.Method);
}
default:
throw new NotSupportedException(node.NodeType.ToString());
}
}
}
Now I'm calling it like
public CustomBo FindBy(Expression<Func<CustomBo, bool>> predicateId)
{
var newPredicate = predicateId.ConvertExpression<CustomBo, Entity>();
}
Still if anyone know how to do it by automapper then plz let me know.
Thanks

Answer 2

Looks like this was added after your asked your question: Expression Translation (UseAsDataSource)
Now all you have to do is dbSet.UseAsDataSource().For<CustomBo>().Where(expression).ToList();. Much nicer!