How to use CLR function at SQL Server?

Creating a CLR function in SQL Server involves the following steps:
1. Define the function as a static method of a class in a language supported by the .NET Framework
2. Register the assembly in SQL Server by using the CREATE ASSEMBLY statement
3. Create the function that references the registered assembly by using the CREATE FUNCTION statement

1. a. Create a SQL Server Project using Visual Studio 2019 or Higher, Named the Project SQLExternalMethods
b. Create a Class MySQLFunctions
c. Add a static Method with SQL function Attribute
namespace SQLExternalMethods
public static class MySQLFunctions
public static SqlString Test(string myString )
return myString .ToUpper();

2. a. Build the Above project and copy the SQLExternalMethods .dll to SQL server Installed Server.
b. Open SSMS and Register the assembly
FROM 'C:\Program Files (x86)\LLM\ SQLExternalMethods .dll ';

3. Now create a SQL function to use the c# methods
CREATE FUNCTION MyToUpper(@myString nvarchar(max)) RETURNS nvarchar(max)
EXTERNAL NAME SQLExternalMethods . MySQLFunctions .Test ;

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