Submitting Requests Synchronously

Work requests can be submitted to a Service synchronously or asynchronously. Let us go through submitting a request synchronously first. Depending on the number of input arguments you have for the Service function, you can use the execute or executeWithArray function.

Both execute functions take in three arguments:

1.

methodName — the name of the method to invoke.

2.

data — the input data.

3.

discriminator — the discriminator used for this request; discriminators are discussed in a later section.

Both return the output data as a string. The input and output arguments are restricted to strings, for reasons of network serialization, and better interoperability between clients and Services of different languages.

The only difference between the two functions is that executeWithArray accepts an array of strings as the input data argument, whereas execute accepts a single string.

For example:

Dim numInMemory As String
numInMemory = service.execute("getMemory", "", Nothing)
Dim sum As String
Dim args(1) As String
args(0) = "25"
args(1) = "75"
sum = service.executeWithArray("add", args, Nothing)

If the Engine-side function being executed takes one or no arguments, it is more convenient to use execute; otherwise, place your arguments in an array, and pass them into executeWithArray. If the function takes no arguments, like the getMemory function, use execute with an empty string.

The execute functions do not return until the Service completes the request and returns the result. To have the function return immediately, use the submit function to submit requests asynchronously, as described below.