Optional Arguments

Normally you must call a GISDK function with values for all of its arguments. However, some functions have optional arguments. If they are not included in the function call, the code will still be allowed by the resource compiler and null will automatically be passed for the missing arguments. This allows Caliper Corporation to add new arguments to existing functions without affecting your code.

Optional arguments are indicated in the syntax by square brackets, as follows:

result = FunctionName(string required [, string optional1[, string optional2][, string optional3]])

There will never be non-optional arguments after optional arguments. You must have the proper number of commas if arguments are left null before an optional argument, but you do not have to have commas after the last optional argument that you use. Using the above example, these syntaxes would all be valid:

result = FunctionName(string required)

result = FunctionName(string required, string optional1)

result = FunctionName(string required, , string optional2)

result = FunctionName(string required, string optional1, , string optional3)

result = FunctionName(string required, , , string optional3)