MVVM Dapper how to save changed collectionitems instantly to database

Question

I've got a question relating the above mentioned topic.

------Using Dapper and Caliburn Micro-----

At the moment im building a mvvm wpf application which displays a list of orders. These orders need some ressources to be allocated so the workprocess can begin.

The list of orders provide a few buttons for each row (order) to start, pause, finish and to set the status of the order like "is material allocated".

Whats a good practise to save changes of the above steps made via the list to database? When creating the order I simply pass the values via a buttonclick to a method in database access project.

For the moment lets just talk about the UIOrderModel and the property IsAllocated

Once the Button (the ugly beige one) is clicked the following method fires:

     public void MatAllocated(UIOrderModel order) {
        order.IsMatAllocated = "Y";
        order.IsAllocated = true;
        order.StatusFlag = MKDataWork.Library.Enums.StatusFlag.allocated;
        OrdersBc.Refresh();
     }

Since it's workig so far as it should be I'm on the question how to store the Information about the changed status of Allocation in my database. By way of example it would be kinda easy just to fire an update query (sp) in the method above.

The collection and the database should always have the same state of data.

The UiOrderModel:

   public class UIOrderModel {
    private UIOrderModel UIorder = null;
    public int Code { get; set; }
    public UIuserModel OrderedByEmp { get; set; }
    public int OrderedByEmpPersId { get; set; }
    public string OrderedByEmpName { get; set; }
    public List<UIAllocationModel> AllocationList {get;set;}
    public DateTime OrderDate { get; set; } 
    public UIDepartmentModel ForDepartment { get; set; }
    public string DepartmentName { get; set; }
    public DateTime ExpectedFinishDate { get; set; }
    public string Project { get; set; }
    public string Commission { get; set; }
    public string IsMatAllocated { get; set; } = "N";
    public bool IsAllocated { get; set; } = false;
    public string Additions { get; set; }
    public StatusFlag StatusFlag { get; set; }
    public decimal? Quantity { get; set; }
    public UnitOfMeasures Unit { get; set; }
    public UIitemModel Item { get; set; }
    public string ItemName { get; set; }
    public string ItemCode { get; set; }
    public DateTime FinishedDateTime { get; set; }
    public UIuserModel FinishedByEmp { get; set; }

    public UIOrderModel() { }

    public UIOrderModel(Dictionary<string,object> entries) {
        int i = 0;

        this.UIorder = this;
        this.Code = int.TryParse(entries["Code"].ToString(), out i) ? i : 0;
        this.OrderedByEmp = (UIuserModel)entries["OrderedByEmp"];
        this.OrderedByEmpPersId = ((UIuserModel)entries["OrderedByEmp"]).PersId;
        this.ForDepartment = (UIDepartmentModel)entries["SelectedDepartment"];
        this.DepartmentName = ((UIDepartmentModel)entries["SelectedDepartment"]).Bezeichnung;
        this.ExpectedFinishDate = (DateTime)entries["ExpectedFinishDate"];
        this.Quantity = (decimal?)entries["Quantity"];
        this.Unit = (UnitOfMeasures)entries["SelectedUnitOfMeasures"];
        this.Item = (UIitemModel)entries["Item"];
        this.ItemName = ((UIitemModel)entries["Item"]).ItemName;
        this.ItemCode = ((UIitemModel)entries["Item"]).ItemCode;
        this.StatusFlag = (StatusFlag)entries["StatusFlag"];
        this.Project = (string)entries["Project"];
        this.Commission = (string)entries["Commission"];
        this.Additions = (string)entries["Additions"];
    }

    public UIOrderModel(int code,string orderedByEmpName, int orderedByEmpPersId, string departmentName, DateTime expectedFinishDate,
                        decimal? quantity, UnitOfMeasures unit, string itemname, string itemcode, string project, string commission,
                        StatusFlag statusFlag, string additions) 
    {
        this.UIorder = this;
        this.Code = code;
        this.OrderedByEmpPersId = orderedByEmpPersId;
        this.OrderedByEmpName = orderedByEmpName;
        this.DepartmentName = departmentName;
        this.ExpectedFinishDate = expectedFinishDate;
        this.Quantity = quantity;
        this.Unit = unit;
        this.ItemName =  itemname;
        this.StatusFlag = statusFlag;
        this.Project = project;
        this.Commission = commission;
        this.Additions = additions;
    }

    public void SaveOrder() {
        OrderModel result = (OrderModel)this;

        result.SaveOrder();
    }

    public static explicit operator OrderModel(UIOrderModel uiOrder) {
        return new OrderModel()
        {
            Code = uiOrder.Code,
            OrderDate = uiOrder.OrderDate,
            OrderedByEmp = (UserModel)uiOrder.OrderedByEmp,
            OrderedByEmpName = $"{uiOrder.OrderedByEmp.FirstName} {uiOrder.OrderedByEmp.LastName}",
            ExpectedFinishDate = uiOrder.ExpectedFinishDate,
            ForDepartment = (DepartmentModel)uiOrder.ForDepartment,
            AllocationList = uiOrder.AllocationList?.Select(am => (AllocationModel)am).ToList(),
            IsMatAllocated = uiOrder.IsMatAllocated,
            Quantity = uiOrder.Quantity,
            Unit = uiOrder.Unit,
            Item = (ItemModel)uiOrder.Item,
            ItemCode = uiOrder.Item.ItemCode,
            ItemName = uiOrder.Item.ItemName,
            Project = uiOrder.Project,
            Commission = uiOrder.Commission,
            StatusFlag = uiOrder.StatusFlag,
            Additions = uiOrder.Additions
        };
    }

    public static explicit operator UIOrderModel(OrderModel order) {
        return new UIOrderModel()
        {
            Code = order.Code,
            OrderDate = order.OrderDate,
            OrderedByEmp = (UIuserModel)order.OrderedByEmp,
            OrderedByEmpName = $"{order.OrderedByEmp.FirstName} {order.OrderedByEmp.LastName}",
            ExpectedFinishDate = order.ExpectedFinishDate,
            ForDepartment = (UIDepartmentModel)order.ForDepartment,
            AllocationList = order.AllocationList?.Select(am => (UIAllocationModel)am).ToList(),
            IsMatAllocated = order.IsMatAllocated,
            Quantity = order.Quantity,
            Unit = order.Unit,
            Item = (UIitemModel)order.Item,
            ItemCode = order.ItemCode,
            ItemName = order.ItemName,
            Project = order.Project,
            Commission = order.Commission,
            StatusFlag = order.StatusFlag,
            Additions = order.Additions
        };
    }
}

But whats the correct MVVM way to accomplish this in a proper manner?

Thanks for an advice!

Answer 1

Well I've been on vacation, returned and had some time and distance to the question above. Yesterday I chose a kinda simple way to solve it.

I've implemented the command pattern and passed the execution through my UI project to the data access. It's just one query for all kinds of statussteps (and the relating table) and updates of the whole order. Therefore I pass an enum value (action), orderNo and Id of the employee as parameter for the method / query.

I'm not completely sure if it's the best mvvm way but its working in a comfortable and fast way.