From Xojo Documentation
Returns the number of characters in the specified string.
|result||Integer||The number of characters in string.|
|stringVariable||String||Any variable of type String.|
Technically, Length returns the number of code points rather than the number of characters. For example, if two code points are presented visually as a single character, its length will be reported as "2", not "1".
This example uses the Length function to return the number of characters in a string.
String for a complete list of functions.