// Define the plan and attach the payment definitions and merchant preferences.
// More Information: https://developer.paypal.com/webapps/developer/docs/api/#create-a-plan
var billingPlan = new Plan
{
name = "Tuts+ Plus",
description = "Monthly plan for courses.",
type = "fixed",
// Define the merchant preferences.
// More Information: https://developer.paypal.com/webapps/developer/docs/api/#merchantpreferences-object
merchant_preferences = new MerchantPreferences()
{
setup_fee = GetCurrency("0"), // $0
return_url = "returnURL", // Retrieve from config
cancel_url = "cancelURL", // Retrieve from config
auto_bill_amount = "YES",
initial_fail_amount_action = "CONTINUE",
max_fail_attempts = "0"
},
payment_definitions = new List<PaymentDefinition>
{
// Define a trial plan that will only charge $9.99 for the first
// month. After that, the standard plan will take over for the
// remaining 11 months of the year.
new PaymentDefinition()
{
name = "Trial Plan",
type = "TRIAL",
frequency = "MONTH",
frequency_interval = "1",
amount = GetCurrency("0"), // Free for the 1st month
cycles = "1",
charge_models = new List<ChargeModel>
{
new ChargeModel()
{
type = "TAX",
amount = GetCurrency("1.65") // If we need to charge Tax
},
new ChargeModel()
{
type = "SHIPPING",
amount = GetCurrency("9.99") // If we need to charge for Shipping
}
}
},
// Define the standard payment plan. It will represent a monthly
// plan for $19.99 USD that charges once month for 11 months.
new PaymentDefinition
{
name = "Standard Plan",
type = "REGULAR",
frequency = "MONTH",
frequency_interval = "1",
amount = GetCurrency("15.00"),
// > NOTE: For `IFNINITE` type plans, `cycles` should be 0 for a `REGULAR` `PaymentDefinition` object.
cycles = "11",
charge_models = new List<ChargeModel>
{
new ChargeModel
{
type = "TAX",
amount = GetCurrency("2.47")
},
new ChargeModel()
{
type = "SHIPPING",
amount = GetCurrency("9.99")
}
}
}
}
};
// Get PayPal Config
var apiContext = PayPalConfiguration.GetAPIContext();
// Create Plan
plan.Create(apiContext);
新创建的结算计划处于 CREATED 状态。将其激活为“活动”状态，以便您的客户可以订阅该计划。要激活该计划，我们需要发出 PATCH 请求：
// Activate the plan
var patchRequest = new PatchRequest()
{
new Patch()
{
op = "replace",
path = "/",
value = new Plan() { state = "ACTIVE" }
}
};
plan.Update(apiContext, patchRequest);
如您所见，PayPal 库是其 REST API 的直接包装器，这很好，但与 Stripe 等其他 API 相比，该 API 也非常复杂。因此，将所有 PayPal 通信包装在对象中，为我们的应用程序提供更清晰、更简单的 API，这确实是一个不错的选择。在这里您可以看到封装在多个带有参数的函数中的代码的样子：
public static Plan CreatePlanObject(string planName, string planDescription, string returnUrl, string cancelUrl,
string frequency, int frequencyInterval, decimal planPrice,
decimal shippingAmount = 0, decimal taxPercentage = 0, bool trial = false, int trialLength = 0, decimal trialPrice = 0)
{
// Define the plan and attach the payment definitions and merchant preferences.
// More Information: https://developer.paypal.com/docs/rest/api/payments.billing-plans/
return new Plan
{
name = planName,
description = planDescription,
type = PlanType.Fixed,
// Define the merchant preferences.
// More Information: https://developer.paypal.com/webapps/developer/docs/api/#merchantpreferences-object
merchant_preferences = new MerchantPreferences()
{
setup_fee = GetCurrency("1"),
return_url = returnUrl,
cancel_url = cancelUrl,
auto_bill_amount = "YES",
initial_fail_amount_action = "CONTINUE",
max_fail_attempts = "0"
},
payment_definitions = GetPaymentDefinitions(trial, trialLength, trialPrice, frequency, frequencyInterval, planPrice, shippingAmount, taxPercentage)
};
}
private static List<PaymentDefinition> GetPaymentDefinitions(bool trial, int trialLength, decimal trialPrice,
string frequency, int frequencyInterval, decimal planPrice, decimal shippingAmount, decimal taxPercentage)
{
var paymentDefinitions = new List<PaymentDefinition>();
if (trial)
{
// Define a trial plan that will charge 'trialPrice' for 'trialLength'
// After that, the standard plan will take over.
paymentDefinitions.Add(
new PaymentDefinition()
{
name = "Trial",
type = "TRIAL",
frequency = frequency,
frequency_interval = frequencyInterval.ToString(),
amount = GetCurrency(trialPrice.ToString()),
cycles = trialLength.ToString(),
charge_models = GetChargeModels(trialPrice, shippingAmount, taxPercentage)
});
}
// Define the standard payment plan. It will represent a 'frequency' (monthly, etc)
// plan for 'planPrice' that charges 'planPrice' (once a month) for #cycles.
var regularPayment = new PaymentDefinition
{
name = "Standard Plan",
type = "REGULAR",
frequency = frequency,
frequency_interval = frequencyInterval.ToString(),
amount = GetCurrency(planPrice.ToString()),
// > NOTE: For `IFNINITE` type plans, `cycles` should be 0 for a `REGULAR` `PaymentDefinition` object.
cycles = "11",
charge_models = GetChargeModels(trialPrice, shippingAmount, taxPercentage)
};
paymentDefinitions.Add(regularPayment);
return paymentDefinitions;
}
private static List<ChargeModel> GetChargeModels(decimal planPrice, decimal shippingAmount, decimal taxPercentage)
{
// Create the Billing Plan
var chargeModels = new List<ChargeModel>();
if (shippingAmount > 0)
{
chargeModels.Add(new ChargeModel()
{
type = "SHIPPING",
amount = GetCurrency(shippingAmount.ToString())
});
}
if (taxPercentage > 0)
{
chargeModels.Add(new ChargeModel()
{
type = "TAX",
amount = GetCurrency(String.Format("{0:f2}", planPrice * taxPercentage / 100))
});
}
return chargeModels;
}
更新结算计划
您可以通过提出“PATCH”请求来更新现有结算方案的信息。这是一个包装该调用的函数：
public static void UpdateBillingPlan(string planId, string path, object value)
{
// PayPal Authentication tokens
var apiContext = PayPalConfiguration.GetAPIContext();
// Retrieve Plan
var plan = Plan.Get(apiContext, planId);
// Activate the plan
var patchRequest = new PatchRequest()
{
new Patch()
{
op = "replace",
path = path,
value = value
}
};
plan.Update(apiContext, patchRequest);
}
要更新计费计划描述，我们可以调用此函数并传递正确的参数：
UpdateBillingPlan(
planId: "P-5FY40070P6526045UHFWUVEI",
path: "/",
value: new Plan { description = "new description" });
public static void ExecuteBillingAgreement(string token)
{
// PayPal Authentication tokens
var apiContext = PayPalConfiguration.GetAPIContext();
var agreement = new Agreement() { token = token };
var executedAgreement = agreement.Execute(apiContext);
}
暂停计费协议
使用此方法暂停协议：
public static void SuspendBillingAgreement(string agreementId)
{
var apiContext = PayPalConfiguration.GetAPIContext();
var agreement = new Agreement() { id = agreementId };
agreement.Suspend(apiContext, new AgreementStateDescriptor()
{ note = "Suspending the agreement" });
}
重新激活计费协议
这个与上一个非常相似：
public static void ReactivateBillingAgreement(string agreementId)
{
var apiContext = PayPalConfiguration.GetAPIContext();
var agreement = new Agreement() { id = agreementId };
agreement.ReActivate(apiContext, new AgreementStateDescriptor()
{ note = "Reactivating the agreement" });
}
取消计费协议
使用此功能取消计划：
public static void CancelBillingAgreement(string agreementId)
{
var apiContext = PayPalConfiguration.GetAPIContext();
var agreement = new Agreement() { id = agreementId };
agreement.Cancel(apiContext, new AgreementStateDescriptor()
{ note = "Cancelling the agreement" });
}
以下のスクリーンショットに示すように、clientId トークンと clientSecret トークンを 
アカウントの作成] をクリックしてください。