protected override LambdaExpression CreateGroupByExpression()
{
var memberAccessBuilder = ExpressionBuilderFactoryEx.MemberAccess(this.Queryable, this.groupDescriptor.MemberType, this.groupDescriptor.Member);
memberAccessBuilder.ParameterExpression = this.ParameterExpression;
return(memberAccessBuilder.CreateLambdaExpression());
}
public MethodCallExpression GetSortExpression()
{
MethodCallExpression mce = null;
bool isFirst = true;
foreach (var descriptor in this.sortDescriptors)
{
Type memberType = typeof(object);
var descriptorBuilder = ExpressionBuilderFactoryEx.MemberAccess(this.parentExpression, memberType, descriptor.Member);
var expression = descriptorBuilder.CreateLambdaExpression();
string methodName = "";
if (isFirst)
{
methodName = descriptor.SortDirection == ListSortDirection.Ascending ?
"OrderBy" : "OrderByDescending";
}
else
{
methodName = descriptor.SortDirection == ListSortDirection.Ascending ?
"ThenBy" : "ThenByDescending";
}
mce = Expression.Call(
typeof(Queryable),
methodName,
new[] { parentExpression.GetUnderlyingElementType(), expression.Body.Type },
isFirst ? parentExpression : mce,
Expression.Quote(expression));
isFirst = false;
}
return(mce);
}
