I'm after a little help with the techniques to use for Databinding. It's been quite a while since I used any proper data binding and want to try and do something with the DataGridView. I'm trying to configure as much as possible so that I can simply designed the DatagridView through the form editor, and then use a custom class that exposes all my information.
The sort of information I've got is as follows:
public class Result
{
public String Name { get; set; }
public Boolean PK { get; set; }
public MyEnum EnumValue { get; set; }
public IList<ResultInfos> { get; set; }
}
public class ResultInfos { get; set; }
{
public class Name { get; set; }
public Int Value { get; set; }
public override String ToString() { return Name + " : " Value.ToString(); }
}
I can bind to the simple information without any problem. I want to bind to the EnumValue with a DataGridViewComboBoxColumn, but when I set the DataPropertyName I get exceptions saying the enum values aren't valid.
Then comes the ResultInfo collection. Currently I can't figure out how to bind to this and display my items, again really I want this to be a combobox, where the 1st Item is selected. Anyone any suggestions on what I'm doing wrong?
Thanks
Before you bind your data to the grid, first set the DataGridViewComboBoxColumn.DataSource like this...
combo.DataSource = Enum.GetValues(typeof(YourEnum));
I generally do this in the constructor after InitializeComponent(). Once this is set up you will not get an exception from the combo column when you bind your data. You can set DataGridViewComboBoxColumn.DataPropertyName at design time as normal.
The reason you get an exception when binding without this step is that the cell tries to select the value from the list that matches the value on the item. Since there are no values in the list... it throws an exception.
Related
I need to implement a way to get the list with the names of all the columns for sorting in the jquery datatables plugin. Currently, this only captures the name of the first column that should be sorted.
var sortingColumnName = Request.Form.GetValues("columns[" + Request.Form.GetValues("order[0][column]")?[0] + "][name]")?[0];
I can not set the string to Request.Form.GetValues.
I need this case, for example.:
"order": [[2, "asc"], [4, "desc"], [3, "desc"]]
When you inspect the elements you can verify that in this example there are three keys to order, but there may be other cases where you have more or fewer keys.
Don't use Request.Form. The issue you're currently having is that you're trying to manually deserialize posted data into some kind of usable data structure. The model binding in ASP.NET MVC already does exactly that.
A model structure that works for DataTables would look something like this:
public class DataTablesRequestViewModel
{
public int draw { get; set; }
public int start { get; set; }
public int length { get; set; }
public IList<DataTablesOrder> order { get; set; } = new List<DataTablesOrder>();
public class DataTablesOrder
{
public int column { get; set; }
public string dir { get; set; }
}
}
You can modify/extend/etc. as you need, but the default posted structure for DataTables should match this. Simply accept this model on your controller action:
public ActionResult YourActionMethod(DataTablesRequestViewModel request)
{
// in here you can get the list of sorted columns from: request.order
}
Here is the problem I need to solve:
I need to display a grid that contains a group of columns that are dynamic, meaning that the number can change depending on the user parameters.
I have attached a sample below as an image to illustrate:
GRID SAME IMAGE
I have these c# POCOs to keep my question simple
public class OrderItem
{
public string ProductName { get; set; }
public string Status { get; set; }
public List<CityOrderInfo> CityOrders { get; set; }
}
public class CityOrderInfo
{
public int OrderCount { get; set; }
}
I have a web api controller that is able to accept the OData request, plus other arguments that the repository accepts. However the problem is that while the parameter $orderby for ProductName and Status works, when I do "$orderby='CityOrders[1]\OrderCount asc' it fails.
public class OrdersControllers : ApiController
{
private readonly IOrdersRepository _repository;
public OrdersControllers(IOrdersRepository repository)
{
this._repository = repository;
}
public IEnumerable<OrderItem> GetOrderItems([FromUri] ODataQueryOptions<OrderItem> oDataQuery)
{
var result = this._repository.GetOrders().ToList();
var queryableData = oDataQuery.ApplyTo(result.AsQueryable());
var transformedData = queryableData as IEnumerable<OrderItem>;
return transformedData;
}
}
The reason I opted to hold the city orders in list is because I thought it would too painful to make a POCO with every city in the USA as a property so instead made it more generic.
The question is how can a sort on a property that holds a list using OData? Is this possible? I keep getting syntax error at position n. As of now I have not found an answer.
I have two domain classes
public class Employee
{
public int Id { get; set; }
public string Name { get; set; }
public Address Address { get; set; }
}
public class Address
{
public string HouseName { get; set; }
public string StreetName { get; set; }
public string PinCode { get; set; }
}
I want to map object of Employee class to another class.
I am using reflection to map empData object to another object. The code i used is
private void GetValues(object empData)
{
System.Type type = empData.GetType();
foreach (PropertyInfo pInfo in type.GetProperties())
{
//do some stuff using this pInfo.
}
}
I could easily map all the properties except the Address property in the emp object which is an object of another class.
So how can i map all the properties irrespective of its type ? i.e, if address contains object of another class it should also get mapped.
Can't you use AutoMapper for mapping classes?
You can know the type of property you are mapping by
if (propertyInfo.PropertyType == typeof(Address))
{ // do now get all properties of this object and map them}
Assuming that you want to be able to do this on any type of object and not just this specific one, you should use some sort of recursive solution. However if it's just for this object - why are you even using reflection? To me it just adds unnecessary complexity to something as simple as mapping six properties to another set of objects.
If you want to get more concrete help with code examples, you'll have to give us some more context. Why does a method named "GetValues" has a return type of void? I have a hard time coding up an example with that in mind. :)
I have something like this in my code and I am getting error: Exception Details: System.ArgumentException: Value cannot be null or empty.
Parameter name: name . What am I doing wrong ? Thanks for help
#model IEnumerable<NHibernateFluentProject.Patient>
#Html.ListBoxFor(model => model, new SelectList(Model,"ID", "FirstName"));
#Html.ListBoxFor is used for your strong typed viewmodel. which could help to bind to your property. First part will take a lambda expression for a single item as a default seleced for your listbox, second part will take the item collections to dispaly all the listbox items.
For example: you have following two classes.
public class HospitalViewModel
{
public string SelectedPatient { get; set; }
public IEnumerable<Patient> AllPatients { get; set; }
}
public class Patient
{
public int Id { get; set; }
public string FirstName { get; set; }
}
From you view, you should do something like
#model HospitalViewModel
#Html.ListBoxFor(model => model.SelectedPatient, new SelectList(Model.AllPatients,"Id", "FirstName"));
OR if you only want to bind all your patients to a listbox, then use Html.ListBox instead
#model IEnumerable<Patient>
#Html.ListBox("ListBoxName", new SelectList(Model,"Id", "FirstName"));
You need to pass a lambda expression containing the property to bind the listbox to.
I am trying to develop a simple MVC 2 timesheet application for my small business.
I have a sort of mock model for now until I have a database in place, just to make things simpler while I develop the functionality. It consists of the following:
public class CustomersRepository
{
public CustomersRepository()
{
Customers = new List<Customer>();
}
public List<Customer> Customers { get; set; }
}
public class Task
{
public Task()
{
Customer = new Customer();
TimeSegments = new List<TimeSegment>();
}
public override string ToString()
{
return Name;
}
public string Name { get; set; }
public Customer Customer { get; set; }
public List<TimeSegment> TimeSegments { get; set; }
}
public class TimeSegment
{
public string Id { get; set; }
public string Date { get; set; }
public int Hours { get; set; }
}
public class Customer
{
//To show the name in the combobox instead of the object name.
public override string ToString()
{
return Name;
}
public Customer()
{
Tasks = new List<Task>();
}
public List<Task> Tasks { get; set; }
public string Name { get; set; }
}
I initialize the repository in the controller, and pass the "model" to the view:
CustomersRepository model = new CustomersRepository();
public ActionResult Index()
{
InitializeRepository();
return View(model);
}
Now, in the view I populate a dropdownlist with the customers:
<div>
<%:Html.DropDownListFor(m => m.Customers, new SelectList(Model.Customers), new {#id="customerDropDownList"}) %>
</div>
But then I need to populate a second dropdownlist (taskDropDownList for the tasks associated with a particular customer) based on the selection the user chooses in the customer dropdownlist.
But how do I do this exactly? I have seen examples with jQuery, but I'm not sure how to apply them to this situation. Also, the examples seem to just populate the lists with string values. I need to be able to access the objects with all their properties. Because the next thing I need to do is to be able to populate the TimeSegments list of the selected task with values from input fields (i.e. the hours worked for particular dates). And for that to be saved to the "model" (eventually to the database) in the controller, how do I get it there, unless the objects are all part of the same model bound to the View?
I'm on rather thin ice with this since I still find the connection between the View and the Controller hard to handle, compared with e.g. Windows development, where these things are rather easy to do. So I would really appreciate a good step by step example if anyone would be so kind as to provide that!
I found the answer here:
http://www.pieterg.com/post/2010/04/12/Cascading-DropDownList-with-ASPNET-MVC-and-JQuery.aspx
It needed some tweaks, and I got help here from CGK. See this post:
Cascading dropdownlist with mvc and jQuery not working