Purchase() public method

Purchases the specified username.
public Purchase ( string username, string password, int packageId, string &errorResponse ) : PurchaseResponse
username string The username.
password string The password.
packageId int The package identifier.
errorResponse string The error response.
return PurchaseResponse
        protected void btnInstall_Click( object sender, EventArgs e )
        {
            StoreService storeService = new StoreService();

            string errorResponse = string.Empty;
            var installResponse = storeService.Purchase( txtUsername.Text, txtPassword.Text, packageId, out errorResponse );
            if ( installResponse != null )
            {
                switch ( installResponse.PurchaseResult )
                {
                    case PurchaseResult.AuthenticationFailed:
                        lMessages.Text = string.Format( "<div class='alert alert-warning margin-t-md'><strong>Could Not Authenticate</strong> {0}</div>", installResponse.Message );
                        break;
                    case PurchaseResult.Error:
                        lMessages.Text = string.Format( "<div class='alert alert-warning margin-t-md'><strong>An Error Occurred</strong> {0}</div>", installResponse.Message );
                        break;
                    case PurchaseResult.NoCardOnFile:
                        lMessages.Text = string.Format( "<div class='alert alert-warning margin-t-md'><strong>No Card On File</strong> No credit card is on file for your organization. Please add a card from your <a href='{0}'>Account Page</a>.</div>", ResolveRockUrl( "~/RockShop/Account" ) );
                        break;
                    case PurchaseResult.NotAuthorized:
                        lMessages.Text = string.Format( "<div class='alert alert-warning margin-t-md'><strong>Unauthorized</strong> You are not currently authorized to make purchases for this organization. Please see your organization's primary contact to enable your account for purchases.</div>" );
                        break;
                    case PurchaseResult.PaymentFailed:
                        lMessages.Text = string.Format( "<div class='alert alert-warning margin-t-md'><strong>Payment Error</strong> An error occurred while processing the credit card on file for your organization. The error was: {0}. Please update your card's information from your <a href='{1}'>Account Page</a>.</div>", installResponse.Message, ResolveRockUrl( "~/RockShop/Account" ) );
                        break;
                    case PurchaseResult.Success:
                        ProcessInstall( installResponse );
                        break;
                }
            }
            else
            {
                lMessages.Text = string.Format( "<div class='alert alert-danger margin-t-md'><strong>Install Error</strong> An error occurred while attempting to authenticate your install of this package. The error was: {0}.</div>", ( string.IsNullOrWhiteSpace( errorResponse ) ? "Unknown" : errorResponse ) );
            }
        }