protected override Expression VisitMethodCall(MethodCallExpression m)
{
switch (m.Method.Name)
{
case "Where":
// ??? this.Visit(m.Arguments[0]);
LambdaExpression lambda = (LambdaExpression)MojioTranslate.StripQuotes(m.Arguments[1]);
this.Visit(lambda.Body);
return(m);
case "Equals":
AddCriteria(m.Object, m.Arguments[0]);
return(m);
case "In":
AddCriteria(m.Arguments[0], m.Arguments[1]);
return(m);
case "Contains":
AddCriteria(m.Arguments[0], m.Object);
return(m);
}
throw new NotSupportedException(string.Format("The method '{0}' is not supported", m.Method.Name));
}
public object Execute(Expression expression)
{
if (expression == null)
{
throw new ArgumentNullException("expression");
}
var callExpression = expression as MethodCallExpression;
if (callExpression != null)
{
Execute(callExpression.Arguments[0]);
switch (callExpression.Method.Name)
{
case "Skip":
_offset = (int)((ConstantExpression)callExpression.Arguments[1]).Value;
break;
case "Take":
_limit = (int)((ConstantExpression)callExpression.Arguments[1]).Value;
break;
case "Where":
_criteria = new MojioCriteriaTranslator().Translate(callExpression, _criteria);
break;
case "OrderByDescending":
_order = MojioTranslate.GetMemberName(callExpression.Arguments[1]);
_desc = true;
break;
case "OrderByAscending":
case "OrderBy":
_order = MojioTranslate.GetMemberName(callExpression.Arguments[1]);
_desc = false;
break;
case "First":
_offset = 0;
_limit = 1;
return(Fetch().First());
case "FirstOrDefault":
_offset = 0;
_limit = 1;
return(Fetch().FirstOrDefault());
case "Count":
return(Count());
case "Any":
return(Count() > 0);
}
}
return(this);
}
private void AddCriteria(Expression left, Expression right, ExpressionType type = ExpressionType.Equal)
{
var memberExpression = MojioTranslate.GetMember(left);
if (memberExpression == null)
{
throw new Exception("Cannot do this?");
}
var key = memberExpression.Member.Name;
var constant = MojioTranslate.EvaluateSubtree(right);
if (type == ExpressionType.Equal)
{
string value = MojioTranslate.GetValue(constant, memberExpression.Type);
criteria.Add(key, value);
}
else if (constant.Value is DateTime)
{
AddDateRange(key, constant, type);
}
}
