Execute Set of ValidationRule-C# Class Design - Better Approach

Question

I have a case there I need to execute set of validation rules for different companies. There will be multiple validation rules against one Company.

So I have following table Structure

Company

ID      CompanyName  
1       ABC   
2       DEF  

ValidationRule

RuleID      Name  
1           Rule1   
2           Rule2 

CompanyValidationRuleMapping

MappingID      CompanyId    RuleID
1              1             1
2              1             2
3              2             2

I have separate stored procedures for every validation rule.

So from my c# code, I will find all validation rule corresponding to a company and need to execute the validation stored procedure associated with that rule.

So I am planning to keep one Interface 'IValidation' which is having different validation methods.

Or

Can i have to create different classes for each validation which implements an interface

Can anyone please suggest a better approach on this.

Answer 1

Your first level of generic validation interface which gives the flexibility of providing both result type and the model to be validated:

public interface IValidate<T, R>
    where T : class
    where R : class // where T is any custom result and R is your custom model
{
    T Validate(R model);
}

Let's say, I need to validate company policies which would be handled by a different sp altogether:

public interface IValidateCompanyPolicies : IValidate<ValidationResult1, Company>
{
  ValidationResult1 Validate(Company model);
}

Again, I also need to check for company monetary accounts, taxes, audits etc:

public interface IValidateCompanyAccounts : IValidate<ValidationResult2, Company>
{
  ValidationResult2 Validate(Company model);
  bool HasAuditPassed(Company model);
}

Resp. classes handling both kinds of IValidate interface

public class ValidateCompanyPolicies : IValidateCompanyPolicies
{
    ValidationResult1 Validate(Company model)
    {
        // Hit stored procedure corresponding to company policies validation
    }
}

public class ValidateCompanyAccounts : IValidateCompanyAccounts
{
    ValidationResult2 Validate(Company model)
    {
        // Hit stored procedure corresponding to company's monetary accounts validation
    }

    bool HasAuditPassed(Company model)
    {
        // Hit stored procedure corresponding to get company audit results
    }
}

My end class which needs to perform all business intensive operations after performing validation:

public class XYZCompany
{
    private IValidateCompanyPolicies companyPoliciesValidation;

    private IValidateCompanyAccounts companyAccountsValidation;

    public XYZCompany(
        IValidateCompanyPolicies companyPoliciesValidation,
        IValidateCompanyAccounts companyAccountsValidation)
    {
        // Perform DI
    }

    public bool UpdateCompany(Company model)
    {
        var checkPolicies = this.companyPoliciesValidation.Validate(model);

        if (checkPolicies.Success)
        {
            var checkAccounts = this.companyAccountsValidation.Validate(model);

            var auditSuccess = this.companyAccountsValidation.HasAuditPassed(model);

            if (checkAccounts.Success && auditSuccess)
            {
                // Perform DB save
            }
        }
    }
}