Thank you for sharing with us your experience, I am glad to help you.
Unfortunately we currently do not support frontend editing and inserting on dynamic items. These operations and the validation logic should be implemented by custom logic. Instead of hardcoding validation in C# code I can suggest you to add validation controls in the ascx file. Here
is a blog post describing how to create User Controls and add validation. The DynamicModulesConfig.config is designed to be used in the backend and if you make any changes they will reflect only the backend form. Please keep in mind that every change to the DynamicModulesConfig.config file will be overwritten when a dynamic content type is updated.
Once you have created your user control you can use Thunder for registering it following these
I hope this information will help you. Please do not hesitate to contact me again if you have any questions or issues.
the Telerik team
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