public Expression CreateInitExpression()
{
List <MemberBinding> bindings = new List <MemberBinding>();
var modelType = ((PropertyInfo)ModelProperty.Member).PropertyType;
var responseType = ResponseProperty.PropertyType;
var props = responseType.GetProperties(BindingFlags.Instance | BindingFlags.Public).Where(x => x.CanWrite);
foreach (var p in props)
{
IncludeTree include;
Expression bind = null;
if (!Includes.TryGetValue(p.Name, out include))
{
NavigationPropertyAttribute navAttr = p.GetCustomAttribute <NavigationPropertyAttribute>();
if (navAttr != null)
{
var navModelProp = Expression.Property(ModelProperty, modelType.GetProperty(navAttr.NavigationProperty));
var navProp = Expression.Property(navModelProp, ((PropertyInfo)navModelProp.Member).PropertyType.GetProperty(navAttr.Property));
bind = navProp;
}
else if (IsMappeable(p))
{
bind = Expression.Property(ModelProperty, modelType.GetProperty(p.Name));
}
}
else
{
bind = include.CreateInitExpression();
}
if (bind != null)
{
bindings.Add(Expression.Bind(p, bind));
}
}
NewExpression newResponse = Expression.New(responseType);
MemberInitExpression initExpression = Expression.MemberInit(newResponse, bindings);
return(initExpression);
}
public Expression <Func <T, TResponse> > Select <TResponse>(string include = null)
{
List <MemberBinding> bindings = new List <MemberBinding>();
foreach (var p in ResponseType.GetProperties(BindingFlags.Instance | BindingFlags.Public).Where(x => x.CanWrite))
{
NavigationPropertyAttribute navAttr = p.GetCustomAttribute <NavigationPropertyAttribute>();
if (navAttr != null)
{
bindings.Add(Expression.Bind(p, Expression.Property(Expression.Property(Parameter, navAttr.NavigationProperty), navAttr.Property)));
}
else if (IncludeTree.IsMappeable(p))
{
bindings.Add(Expression.Bind(p, Expression.Property(Parameter, p.Name)));
}
}
if (!string.IsNullOrWhiteSpace(include))
{
var incTrees = IncludeTree.Build(include, ResponseType, ModelType, Parameter);
foreach (var item in incTrees)
{
bindings.Add(Expression.Bind(item.ResponseProperty, item.CreateInitExpression()));
}
}
MemberInitExpression initExpression = Expression.MemberInit(Expression.New(typeof(TResponse)), bindings);
Expression current = Parameter;
while (current != null && !(current is ParameterExpression))
{
current = ((MemberExpression)current).Expression;
}
return(Expression.Lambda <Func <T, TResponse> >(initExpression, (ParameterExpression)current));
}
