C# IAuthorizationPolicy接口代碼示例

public class MyAuthorizationPolicy : IAuthorizationPolicy
{
    string id;

    public MyAuthorizationPolicy()
    {
        id =  Guid.NewGuid().ToString();
    }

    public bool Evaluate(EvaluationContext evaluationContext, ref object state)
    {
        bool bRet = false;
        CustomAuthState customstate = null;

        // If state is null, then this method has not been called before, so 
        // set up a custom state.
        if (state == null)
        {
            customstate = new CustomAuthState();
            state = customstate;
        }
        else
        {
            customstate = (CustomAuthState)state;
        }

        Console.WriteLine("Inside MyAuthorizationPolicy::Evaluate");

        // If claims have not been added yet...
        if (!customstate.ClaimsAdded)
        {
            // Create an empty list of Claims.
            IList<Claim> claims = new List<Claim>();

            // Iterate through each of the claim sets in the evaluation context.
            foreach (ClaimSet cs in evaluationContext.ClaimSets)
                // Look for Name claims in the current claim set.
                foreach (Claim c in cs.FindClaims(ClaimTypes.Name, Rights.PossessProperty))
                    // Get the list of operations the given username is allowed to call.
                    foreach (string s in GetAllowedOpList(c.Resource.ToString()))
                    {
                        // Add claims to the list.
                        claims.Add(new Claim("http://example.org/claims/allowedoperation", s, Rights.PossessProperty));
                        Console.WriteLine("Claim added {0}", s);
                    }

            // Add claims to the evaluation context.
            evaluationContext.AddClaimSet(this, new DefaultClaimSet(this.Issuer,claims));

            // Record that claims have been added.
            customstate.ClaimsAdded = true;

            // Return true, which indicates this need not be called again.
            bRet = true;
        }
        else
        {
            // This point should not be reached, but just in case...
            bRet = true;
        }

        return bRet;
    }
    public ClaimSet Issuer
    {
        get { return ClaimSet.System; }
    }

    public string Id
    {
        get { return id; }
    }

    // This method returns a collection of action strings that indicate the 
    // operations that the specified username is allowed to call.
    private IEnumerable<string> GetAllowedOpList(string username)
    {
        IList<string> ret = new List<string>();
    
        if (username == "test1")
        {
            ret.Add ( "http://Microsoft.ServiceModel.Samples/ICalculator/Add");
            ret.Add ("http://Microsoft.ServiceModel.Samples/ICalculator/Multiply");
            ret.Add("http://Microsoft.ServiceModel.Samples/ICalculator/Subtract");
        }
        else if (username == "test2")
        {
            ret.Add ( "http://Microsoft.ServiceModel.Samples/ICalculator/Add");
            ret.Add ("http://Microsoft.ServiceModel.Samples/ICalculator/Subtract");
        }
        return ret;
    }

    // internal class for state
    class CustomAuthState
    {
        bool bClaimsAdded;

        public CustomAuthState()
        {
            bClaimsAdded = false;
        }

        public bool ClaimsAdded { get { return bClaimsAdded; } 
                                  set {  bClaimsAdded = value; } }
    }
}