如何使用数据注释将int ID转换为字符串ID

I am using Entity Framework code first approach and would like to have a class with a string that increments as my Id. I have the following code in my sql server that will do this for me but I cannot do the update-database in Package Manager, if I do it will erase the class attribute for the incrementing string. Here is the Sql code:I am using Entity Framework code first approach