protected override Expression VisitMethodCall(MethodCallExpression m)
{
if (m.Method.Name == "Where")
{
_sql.Append(" WHERE ");
SheetType = m.Type.GetGenericArguments()[0];
ReturnType = SheetType;
this.Visit(m.Arguments[1]);
}
else if (IsRowMethodCall(m))
{
if (m.Object.As<MethodCallExpression>().Arguments[0].As<ConstantExpression>().Type == typeof(int))
throw new ArgumentException("Cannot use column indexes in where clause");
string columnName = m.Object.As<MethodCallExpression>().Arguments[0].As<ConstantExpression>().Value.ToString();
_sql.Append(string.Format("[{0}]", columnName));
}
else if (m.Method.Name == "Select")
{
SheetType = m.Method.GetGenericArguments()[0];
ReturnType = m.Method.GetGenericArguments()[1];
if (m.Arguments[0].NodeType != ExpressionType.Constant)
this.Visit(m.Arguments[0]); //Where clause
NewExp = m.Arguments[1].As<UnaryExpression>().Operand;
}
else
{
object methodObject = ((ConstantExpression)m.Object).Value;
object returnValue = m.Invoke();
_params.Add(new OleDbParameter("?", returnValue));
_sql.Append("?");
}
return m;
}
