Message - Request\Response code analysis

Guest User

Hi

Im working from an existing code base in order to replicate and implement the Message based Request\Response architecture and wondered if I could be corrected (if needed) on the below code snippet next to my comments please.

// Method declaration which Returns the CustomerResponse type and accepts an input arguement of type CustomerRequest.

public CustomerResponse GetCustomers(CustomerRequest request)

// Local variable declaration which creates an instance of the CustomerReponse and stores the object in the local variable named response.

var response = new CustomerResponse(request.RequestId);

// Sets or Sets the Criteria and which stores it in the local variable criteria?

var criteria = request.Criteria as CustomerCriteria;

// Gets the SortExpression property and stores it in the sort local variable

string sort = criteria.SortExpression;

// Checks if the LoadOptions property contains a string name Customers.

if (request.LoadOptions.Contains("Customers"))

// Creates an enumerable of type Customer called customers.

IEnumerable customers;

// If the Criteria does not use the IncludeOrderStatistics property

if (!criteria.IncludeOrderStatistics)

// Invoke the GetCustomers and store the return value in the local variable named customers

customers = _customerDao.GetCustomers(sort);

// Otherise store the GetCustomersWithOrderStatistics in the customers local variable instead

customers = _customerDao.GetCustomersWithOrderStatistics(sort);

/ Set the response Customer property to the customers local variable and run a lambda which will translate to the correct DTO object.

response.Customers = customers.Select(c => Mapper.ToDataTransferObject(c)).ToList();

// Get and store the return value of the Getcustomer method into the local variable named customer.

var customer = _customerDao.GetCustomer(criteria.CustomerId);

// Check if the request LoadOptions property holds the string Orders

if (request.LoadOptions.Contains("Orders"))

// Set the customer Orders property to the GetOrdersByCustomer method.

customer.Orders = _orderDao.GetOrdersByCustomer(customer.CustomerId);

// Set the ToDTO method to the response Customer property.

response.Customer = Mapper.ToDataTransferObject(customer);

// Return the value of the response object.

return response;

Thanks!

5 Replies

Know the answer? Post it — somebody with the same question will find it here.

Vulpes14y ago
Accepted answer
Just a few minor changes to the descriptions as I think you've essentially understood it:

// Method declaration which Returns the CustomerResponse type and accepts an input arguement of type CustomerRequest.

public CustomerResponse GetCustomers(CustomerRequest request)

// Local variable declaration which creates an instance of the CustomerReponse and stores the object in the local variable named response.

var response = new CustomerResponse(request.RequestId);

// Gets the Criteria property, casts it to the CustomerCriteria type, and stores it in the local variable named criteria.

var criteria = request.Criteria as CustomerCriteria;

// Gets the SortExpression property and stores it in the sort local variable

string sort = criteria.SortExpression;

// Checks if the LoadOptions property contains a string name Customers.

if (request.LoadOptions.Contains("Customers"))

// Creates a local variable of type IEnumerable called customers.

IEnumerable customers;

// If the Criteria does not use the IncludeOrderStatistics property

if (!criteria.IncludeOrderStatistics)

// Invoke the GetCustomers method and store the return value in the local variable named customers

customers = _customerDao.GetCustomers(sort);

// Otherwise invoke the GetCustomersWithOrderStatistics method and store the return value in the customers local variable instead.

customers = _customerDao.GetCustomersWithOrderStatistics(sort);

// Set the response Customers property to the result, expressed as a List, of running a lambda on the customers collection which will translate to the correct DTO object.

response.Customers = customers.Select(c => Mapper.ToDataTransferObject(c)).ToList();

// Get and store the return value of the Getcustomer method into the local variable named customer.

var customer = _customerDao.GetCustomer(criteria.CustomerId);

// Check if the request LoadOptions property holds the string Orders

if (request.LoadOptions.Contains("Orders"))

// Set the customer Orders property to the return value of the GetOrdersByCustomer method.

customer.Orders = _orderDao.GetOrdersByCustomer(customer.CustomerId);

// Set the response.Customer property to the return value of the ToDTO method.

response.Customer = Mapper.ToDataTransferObject(customer);

// Return the value of the response object.

return response;
Vulpes14y ago
That would make sense, Amit, as the .NET GridView does have a SortExpression property which probably operates in a similar fashion:

http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.gridview.sortexpression.aspx
Amit Choudhary14y ago
The code looks like you're using Dev Express AspxGridView ...
Vulpes14y ago
Well, these don't appear to be .NET Framework types so I can only guess what they're doing from the names of the members.

But, I'd expect a SortExpression property to be expressing how some table (perhaps 'criteria' here) is automatically sorted as elements are added to it.

I'd also expect it to take this sort of form:

"Column1 Asc, Column2 Desc"

which means sort first by Column1 in ascending order and then (if two rows have the same value for Column1) by Column2 in descending order.

It might also be as simple as this:

"Column3"

which means sort by Column3 in ascending order (usually the default).
Guest User14y ago
Hi Vulpes

Given the expression declaration

string sort = criteria.SortExpression;
// Gets the SortExpression property and stores it in the sort local variable

There is no logic defined in the SortExpression its just simply an Automatic property, so what exactly would the local variable sort be storing? I dont see what the benefit would be of storing this property, what is to be had from it?

Thanks

Steven