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ADD Error on Grid Control

I have been working with the Blazor Grid and Hierachal edits.  I am able to display the hierarch without an issue.

For the parent record, the CRUD operations work.  For the child record, I am getting the following error when I use ADD or EDIT.  I was suspecting a Primary Key issue, but that does not seem to be by case.  I am hoping you can provide a few insights on this error. 

Thanks for any information you can provide on this.  Marc.

Uncaught (in promise) Error: System.InvalidOperationException: Unable to create EditContext from type serverAuthTest.shared.Def.VUserRole, handle object creation or give EditContext using OnActionBegin event. For batch editing use OnBatchAdd and OnCellEdit events to provide new item.
   at Syncfusion.Blazor.Grids.Internal.Edit`1.EnsureDataAndEditContext(Object& data, ActionEventArgs`1 actionArgs, BeforeBatchAddArgs`1 batchAddArgs, CellEditArgs`1 cellEditArgs)
   at Syncfusion.Blazor.Grids.Internal.Edit`1.AddRecord(Object data, Nullable`1 index)
   at Syncfusion.Blazor.Grids.SfGrid`1.AddRecord()
   at Syncfusion.Blazor.Grids.Internal.GridToolbar`1.ToolbarClickHandler(ClickEventArgs args)
   at Microsoft.AspNetCore.Components.ComponentBase.CallStateHasChangedOnAsyncCompletion(Task task)
   at Syncfusion.Blazor.Navigations.SfToolbar.TriggerClickEvent(MouseEventArgs e, Boolean isPopupElement, Boolean isCloseIcon, Nullable`1 trgParentDataIndex, String id, Nullable`1 tabItemIndex)
    at Tt.endInvokeDotNetFromJS (blazor.server.js:1)
    at blazor.server.js:1
    at Array.forEach (<anonymous>)
    at Tt._invokeClientMethod (blazor.server.js:1)
    at Tt._processIncomingData (blazor.server.js:1)
    at bt.Tt.connection.onreceive (blazor.server.js:1)
    at WebSocket.o.onmessage (blazor.server.js:1)
endInvokeDotNetFromJS @ blazor.server.js:1
(anonymous) @ blazor.server.js:1
_invokeClientMethod @ blazor.server.js:1
_processIncomingData @ blazor.server.js:1
Tt.connection.onreceive @ blazor.server.js:1
o.onmessage @ blazor.server.js:1


The HTML for the child portion of the Grid is as follows:

 @*Child table *@
    <GridTemplates>
        <DetailTemplate>
            @{
                var vHdr = (context as User);
                var parentPK = vHdr.Id;

                <SfGrid DataSource="@AllUserRoles"
                    AllowResizing="true"
                    Query="@(new Query().Where("UserId", "equal", vHdr.Id))"
                    Toolbar="@(new List<string>() { "Add","Edit", "Delete", "Update", "Cancel" })">

                    <GridEditSettings AllowAdding="true"
                                  AllowDeleting="true"
                                  AllowEditing="true"
                                  ShowDeleteConfirmDialog="true"
                                  Mode="EditMode.Normal"/>

                    @*GridEvents OnActionBegin="ActionBeginHandlerChild" OnActionComplete="ActionCompleteHandlerChild" TValue="FieldAlias"></GridEvents> *@

                    @*child table col headings*@
                    <GridColumns>
                        <GridColumn Field=@nameof(VUserRole.RoleId) HeaderText="Role ID" TextAlign="TextAlign.Left" LockColumn="true" AllowAdding="true" Width="2"> </GridColumn>
                        <GridColumn Field=@nameof(VUserRole.UserId) HeaderText="UserID" Width="3" TextAlign="TextAlign.Left" />
                        <GridColumn Field=@nameof(VUserRole.RoleUser) HeaderText="RoleUser" Width="4" TextAlign="TextAlign.Left" IsPrimaryKey="true" LockColumn="false" AllowAdding="true" />
                    </GridColumns>

                </SfGrid>
            }
        </DetailTemplate>
    </GridTemplates>

The class used for @AllUserRoles is:

namespace serverAuthTest.shared.Def
{
    public class VUserRole
    {
        public VUserRole() { }

        public VUserRole(string roleid, string userid, string roleuser)
        {
            RoleId = roleid;
            UserId = userid;
            RoleUser = roleuser;
        }

        public string RoleId { get; set; }
        public string UserId { get; set; }
        [Key]
        public string RoleUser { get; set; }
    }
}


5 Replies
RN Rahul Narayanasamy Syncfusion Team November 16, 2021 01:34 PM UTC

Hi Marc, 

Greetings from Syncfusion. 
 
Query: ADD Error on Grid Control 

We have validated your query with the provided details and based on your case we suggest you to assign a custom object in OnActionBegin arguments(for normal and dialog editing) and OnBatchAdd and OnCellEdit events for batch editing. 


Since you have used dialog editing, you can resolve the reported problem by adding the below codes in OnActionBegin event. Find the below code snippets and sample for your reference. 

<SfGrid DataSource="@Orders" Toolbar="@(new List<string>() { "Add", "Edit", "Delete", "Update", "Cancel" })"> 
    <GridEditSettings AllowEditing="true" AllowAdding="true" AllowDeleting="true" Mode="EditMode.Dialog"></GridEditSettings> 
    <GridColumns> 
        . . . 
    </GridColumns> 
    <GridEvents TValue="Order" OnActionBegin="ActionBegin"></GridEvents> 
</SfGrid> 
 
@code { 
 
    . . . 
 
    public void ActionBegin(ActionEventArgs<Order> arg) 
    { 
        //Handles add operation 
        if (arg.RequestType.Equals(Syncfusion.Blazor.Grids.Action.Add)) 
        { 
            arg.Data = new Order(0) { CustomerID = "Customer ID" }; 
        } 
 
        //Handles edit operation. During edit operation, original object will be cloned. 
        if (arg.RequestType.Equals(Syncfusion.Blazor.Grids.Action.BeginEdit)) 
        { 
            arg.Data = new Order(arg.RowData.OrderID) 
            { 
                CustomerID = arg.RowData.CustomerID, 
                Freight = arg.RowData.Freight, 
                OrderDate = arg.RowData.OrderDate 
            }; 
        } 
    } 
 
    // This class does not contain any parameter-less constructor, hence this cannot be instantiated using Activator.CreateInstance. 
    public class Order 
    { 
        public Order(int? orderid) => OrderID = orderid; 
 
        public int? OrderID { get; set; } 
        public string CustomerID { get; set; } 
        public DateTime? OrderDate { get; set; } 
        public double? Freight { get; set; } 
    } 
} 

Please let us know if you have any concerns. 

Regards, 
Rahul 


MA Marc November 16, 2021 02:58 PM UTC

Thanks. 

Your suggestion worked, but I do not understand why.  If you look at the original thread

In the link you provided, it states the following - namely I should not need the onAction begin event .    For the VUserRole class, I defined a parameterless constructor.  Should this be enough not to require explicitly declaring it?  

Grid uses Activator.CreateInstance<TValue>() to create or clone new record instance during add and edit operations, so it is must to have parameterless constructor defined for the model class.

There are cases where custom logic is required for creating new object or new object instance cannot be created using Activator.CreateInstance<TValue>(). In such cases you can provide model object instance manually using events.


My next question is for the following block of code.  If I put a debug stop event on the highlighted line, it does not seem to be hit.  Thoughts.


public async Task ActionBeginHandlerChild(ActionEventArgs<VUserRole> Args)
        {
            if (Args.RequestType.Equals(Syncfusion.Blazor.Grids.Action.Save))
            {
                if (Args.Action == "Add")
                {
                    Args.Data = new VUserRole("r1", "u1", "r1u1");
                    //Args.Data = new VUserRole(0) { RoleId = "r1", UserId = "u1", RoleUser = "r1u1" };
                    //InjUserDataSvc.AddNew(Args.Data);
                }
                else


RN Rahul Narayanasamy Syncfusion Team November 17, 2021 02:04 PM UTC

Hi Marc, 

Query: In the link you provided, it states the following - namely I should not need the onAction begin event .    For the VUserRole class, I defined a parameterless constructor.  Should this be enough not to require explicitly declaring it? 

We have validated your query and checked the reported case at our end. While defining a parameter-less constructor, we don’t need to define the mentioned codes in OnActionBegin event as mentioned by previous update.  

Here, we have defined a parameter-less constructor and have not added the codes in OnActionBegin event. Now while editing/adding the record, the error was not thrown. Find the below sample for your reference. 


If you are still facing the problem, then could you please share the below details. It will be helpful to validate and provide a better solution. 

  • Reproduce the problem in the provided sample and revert back to us.
  • Share a simple reproduceable sample if possible.

Query: My next question is for the following block of code.  If I put a debug stop event on the highlighted line, it does not seem to be hit.  Thoughts. 

We have validated your query and in your code snippets you have checked the condition while RequestType as Save. So the mentioned line will be hit while saving the record. It will not hit start editing. 

Regards, 
Rahul 


MA Marc November 17, 2021 06:52 PM UTC

Thanks for your help..  I think I am good.  Marc.


RN Rahul Narayanasamy Syncfusion Team November 18, 2021 04:57 AM UTC

Hi Marc, 
 
Thanks for the update.  Please get back to us if you need further assistance. 
 
Regards, 
Rahul 


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