Hacker’s Guide to Visual FoxPro
An irreverent look at how Visual FoxPro really works. Tells you the inside scoop on every command, function, property, event and method of Visual FoxPro.
ALEN()
This function returns the number of elements, rows or columns in an array. For one-dimensional arrays, it returns the number of elements. For two-dimensional arrays, a parameter determines whether it returns elements, rows or columns. We often forget to include the parameter when asking for rows and end up with elements by accident. A better approach is to always pass 1 for the second parameter unless you specifically want the number of columns. With a one-d array, you still get the number of elements, but for a two-d array, you’ll get rows, which is what we almost always want.
Usage
nReturnValue = ALEN( ArrayName [, nElemRowOrCol ] )
|
Parameter |
Value |
Meaning |
|
ArrayName |
Array Name |
The array whose elements, rows or columns are to be counted. Can be either one- or two-dimensional. |
|
nElemRowOrCol |
0 or Omitted |
Returns the number of elements in the array. |
|
1 |
Returns the number of rows in a two-dimensional array. For a one-dimensional array, returns the number of elements. |
|
|
2 |
Returns the number of columns in a two-dimensional array. Returns 0 for a one-dimensional array. |
|
|
nReturnValue |
Numeric |
The number of elements, rows or columns in ArrayName. |
Example
USE Employee
COPY TO ARRAY aEmps FIELDS Last_Name, First_Name
nCount = ALEN(aEmps,1)
* check if an array is two-dimensional
IF ALEN(MyArray, 2) = 0
* one-dimensional
ELSE
* two-dimensional
ENDIF
Also, see the function aColCopy() under ACOPY() for examples of ALEN() in use.
See Also
ACopy(), AElement(), Array Manipulation, ASubscript(), Dimension