We use cookies to give you the best experience on our website. If you continue to browse, then you agree to our privacy policy and cookie policy. Image for the cookie policy date
Unfortunately, activation email could not send to your email. Please try again.
Syncfusion Feedback

ColumnTemplate InvalidCastException GUID type property

Thread ID:





146278 Jul 29,2019 01:21 PM UTC Jul 31,2019 11:28 AM UTC Blazor 3
Tags: Grid
Karl Posch
Asked On July 29, 2019 01:41 PM UTC

Hello everyone,

I am running into an InvalidCastException when using a class with a property of type GUID. I believe that the at Syncfusion.EJ2.Blazor.BaseComponent.ChangeType method has problems converting a string value into a GUID object. 

System.InvalidCastException: Invalid cast from 'System.String' to 'System.Guid'.
   at System.Convert.DefaultToType(IConvertible value, Type targetType, IFormatProvider provider)
   at System.String.System.IConvertible.ToType(Type type, IFormatProvider provider)
   at System.Convert.ChangeType(Object value, Type conversionType, IFormatProvider provider)
   at System.Convert.ChangeType(Object value, Type conversionType)
   at Syncfusion.EJ2.Blazor.BaseComponent.ChangeType(Object value, Type conversionType)
   at Syncfusion.EJ2.Blazor.BaseComponent.GetObject(Dictionary`2 Data, Type ModelType)
   at Syncfusion.EJ2.Blazor.Grids.GridColumn.BuildRenderTree(RenderTreeBuilder builder)
   at Microsoft.AspNetCore.Components.ComponentBase.<.ctor>b__5_0(RenderTreeBuilder builder)
   at Microsoft.AspNetCore.Components.Rendering.ComponentState.RenderIntoBatch(RenderBatchBuilder batchBuilder, RenderFragment renderFragment)
   at Microsoft.AspNetCore.Components.Rendering.Renderer.RenderInExistingBatch(RenderQueueEntry renderQueueEntry)
   at Microsoft.AspNetCore.Components.Rendering.Renderer.ProcessRenderQueue()
Microsoft.AspNetCore.Routing.EndpointMiddleware: Information: Executed endpoint '/_blazor'
Microsoft.AspNetCore.Hosting.Diagnostics: Information: Request finished in 6272.542600000001ms 101 

I am trying to dynamically create the columns for the grid, as these are basically dependent on a Dictionary inside my DynamicEntity class. 
For this I do overwrite the column template, to define how the grid can access the dictionary values.

Below my code for the grid. I did include it as link to PasteBin, as I could not find anything to include code directly into the forum thread.

@code section of the component:

And within my DynamicEntity class there exists a property of type Guid. As Guid does not implement the IConvertible interface, I think here lies the problem.

Is there some kind of possibility to attach a convertor to the Grid ? The only other solution for this problem which comes to my mind would be to implement something like a custom ConvertibleGuid-Type which does implement IConvertible.

Thank you for your help.

Best Regards,


Renjith Singh Rajendran [Syncfusion]
Replied On July 30, 2019 01:31 PM UTC

Hi Karl,  

We have validated the defect you have initiated with us. Thank you for taking the time to report this issue “Script error : Invalid cast from 'System.String' to 'System.Guid'.” and helping us improve our product. At Syncfusion, we are committed to fixing all validated defects (subject to technological feasibility and Product Development Life Cycle ) and including the defect fix in our subsequent Nuget release which is expected to be roll out on or before August 19th 2019. 
You can now track the current status of your request, review the proposed resolution timeline, and contact us for any further inquiries through this link. 

Till then we appreciate your patience. 

Renjith Singh Rajendran. 

Karl Posch
Replied On July 30, 2019 02:48 PM UTC

Hello Renjith,

thank you for your reply. I am looking forward for the next release. Would it be possible for me to fix this issue in the meantime by creating my own CustomGridColumn, which does derive from the Syncfusion.EJ2.Blazor.Grids.GridColumn? This class would then simply have its own ChangeType Method, which does some own conversion logic if the type happens to be a Guid. Otherwise it would call the method of the base class.

Best Regards,


Vignesh Natarajan [Syncfusion]
Replied On July 31, 2019 11:28 AM UTC

Hi Karl,  

Thanks for your update.  

Query: “Would it be possible for me to fix this issue in the meantime by creating my own CustomGridColumn, which does derive from the Syncfusion.EJ2.Blazor.Grids.GridColumn? 

No. Because we have used Blazor’s renderFragment concept to render the templates in Blazor Grid. So while using this concept, we will serialize the model class during the rendering which will contain the GUID property and exception will occur at that time itself even if we extend and use CustomGridColumn. Hence it is not feasible to achieve through any workaround. So we appreciate your patience until then. 

We will get back to you once the reported issue is fixed.    

Vignesh Natarajan. 


This post will be permanently deleted. Are you sure you want to continue?

Sorry, An error occured while processing your request. Please try again later.

Please sign in to access our forum

This page will automatically be redirected to the sign-in page in 10 seconds.

Warning Icon You are using an outdated version of Internet Explorer that may not display all features of this and other websites. Upgrade to Internet Explorer 8 or newer for a better experience.Close Icon

Live Chat Icon For mobile
Live Chat Icon