How to make a shipping method availability dependent on a custom configuration value?

[arvindporiya92 (Aryan)]

Example i have add new custome field COD in “extra_fees” and set value 15…in checkout page How to check COD method in (‘extra_fees’ ==15) { isAvailble= true; } which Plugin/Observer Use in magento2?

[dmitry_fedyuk (Dmitrii Fediuk)]

You can programmatically manage a shipping carrier’s, method’s, or rate’s availability by implementing the following methods:

• \Magento\Shipping\Model\Carrier\AbstractCarrierInterface::isActive()
• \Magento\Shipping\Model\Carrier\CarrierInterface::getAllowedMethods()
• \Magento\Shipping\Model\Carrier\AbstractCarrierInterface::collectRates()