dbContext验证属性模型单元测试

Question

UserViewModel包含使用存储库的验证属性。如何将存储库的DbContext传递到验证属性？

[Test]
public void Test()
{
    MainContext  dbContext = new MainContext();

    UserViewModel user = new UserViewModel()
    {
         UserName = "unit_test"              
    };

    //How to pass dbContext?
    var context = new ValidationContext(user, null, null);
    var results = new List<ValidationResult>();
    Assert.IsTrue(Validator.TryValidateObject(user, context, results, true));
}