In a page I invoked a data source getTblImployeeByEmployeeID, then create a parameter Employee_ID, then run my project, it inform error ".....razor.designer.cs(310,95): error CS0103: The name 'Employee_ID' does not exist in the current context". I have not understood the logic of Radzen then I can not fix it.
How is that page open? Does it have such a parameter defined when it is open (either via dialog or navigation)? Shows us the event which opens the page.
I am confused. The original error you reported is about Employee_ID. The screenshots you paste are about NhanVien_ID. Is that the same case? What is the code generated for that page? The *.designer.cs file contains code for all parameters in the form: