For Statements

You use a for statement to create loops based on a counter variable:

for variable = start_value to finish_value [step step_size] do

end

The start_value, finish_value, and step_size must all be numeric. For example:

for i = 1 to 10 do

arr[i] = i * i

end

for j = 20 to 0 step -2.5 do

RunMacro("check distance", j)

end

The contents of the loop are executed once for each value of the looping variable. The looping variable is initialized to start_value and compared to finish_value each time the GISDK macro is about to enter the loop. If the looping variable has passed finish_value, the loop terminates. If start_value is greater than finish_value, therefore, the contents of the loop will not be executed at all (unless the step_size is negative).

You can use a break statement to exit the smallest enclosing loop. For example:

for i = 1 to 10 do

ShowMessage("i="+String(i))

if i = 5 then break // only the first five messages will be displayed

end

You can use a continue statement to go to the next iteration of the smallest enclosing loop. For example:

for i = 1 to 10 do

if i > 5 then continue // the last five messages will not be displayed

ShowMessage("i="+String(i))

end

Iterating over Collections

You can also iterate over a collection, similar to foreach loops in other languages:

for item in collection do

end

where item is a variable name that gets assigned the next element of the collection on each pass through the loop. You should not use this statement when the set of elements contained by the collection changes during the execution of the loop.

The collection can be any of the following:

Collection Type	Items	Notes
Array	Elements
Vector	Elements
String	Characters
File	Lines	Must be opened in text mode
COMObject	Elements	Must have an enumerator property that supports the IEnumVARIANT interface
ManagedObject	Elements	Must implement the IEnumerable interface
DataCursor	Records
MatrixCurrency	Vectors