JSON-based custom service with parameters (AX 7)

Dynamics 365 for Operations deploys custom web services in two ways: as SOAP-based services and JSON-based services. AX developers are often familiar with SOAP services (which were used in AX 2012), but JSON-based ones are new to them.

One particular challenge is passing arguments to a service. Let’s say we have an Add operation, which can sum two numbers.

public int Add(int a, int b)
{
    return a + b;
} int Add(int a, int b)
{
    return a + b;
}

To call the service, we have to provide values for both arguments, <