Arrays

Arrays make it possible for you to refer to a series of variables by the same name and to use an index to tell them apart. This helps you create smaller and simpler code in many situations, because you can set up loops that deal efficiently with any number of cases by using the index number. Arrays are useful when you must store a number of values, but you do not know how many, or you do not want to create individual variables to store them all.

For example, suppose you must store a numeric value for every day of the year. You could declare 365 separate numeric variables, but that would be a lot of work. Instead, you can create an array to store all the data in one variable. The array itself is a single variable with multiple elements; each element can contain one piece of data.

You can use loops, together with a couple of special functions for working with arrays, to assign values to or retrieve values from the various elements of an array.

Creating array

To declare an array variable use the following statement:

array A

All arrays are dynamically resizable. So you don't have to worry about the size of array.

Assigning array variable

The following example creates 30 elements in the array A and assigns the values to array elements

array A

inti

for (i=0; i<30; i++)

    A[i] = i

endfor

Accessing array variables

The following example demonstrates how array variable can be accessed:

array A

inti

for (i=0; i<30; i++)

    A[i] = i

endfor

for (i=0; i<30; i++)

    Println(A[i])

endfor

When the size of array is unknown the size can be obtained using GetArraySize() function:

array A

inti

for (i=0; i<30; i++)

    A[i] = i

endfor

intnSize = GetArraySize(A)

for (i=0; i<nSize; i++)

    Println(A[i])

endfor

Unknown arrays can be traversed. The following example demonstrate such technique:

arrayA = GetArray() # some function that returns array

intnSize = GetArraySize(A)

intnPosition = 0

stringsIndex

for(nPosition = 0; nPosition < nSize; nPosition ++)

# Position represents the phisical location of the array element

# sIndex is the real index of the array element

sIndex = GetArrayIndex(A, nPosition)

Println(A[sIndex])

endfor

Using multidimensional arrays

You can create multidimensional arrays. A multidimensional array uses more than one index to access data. Multidimensional arrays are arrays of arrays, where each sub-array can have a different length.

For example, two-dimensional array presents the table. The following example demonstrates how to use two-dimensional arrays to query the database. There is table 'Person' in the database that contains the following data:

stringsConnectionString = "DSN=PRESIDENTS"

intnID = DBOpen(sConnectionString)

if( nID > 0)

    array Result = DBSelect(nID, "select * from Person")

if (DBGetSQLStatus(nID) != SQLOK)

    Println(DBGetSQLErrorString(nID))

else

    int nPosition

    string sIndex

    for(nPosition=0; nPosition < GetArraySize(Result),; nPosition++)

        sIndex = GetArrayIndex(Result, nPosition)

        Println(Result[sIndex]["FirstName"], " ", Result[sIndex]["LastName"])

endfor

endif

endif

DBClose(nID)

The output of the script:

George Washington

John Kennedy