chk()

Syntax

chk(string1,string2,string3)

Description

Returns true or false depending on a character-by-character comparison of string1 with string2 and string3 using the ASCII value of each character for the basis of the comparison.

Firstly, each character of string2 is compared with the corresponding character of string1 to ensure that, for each character, string2<=string1. A character is said to be less than or greater than another character if its ASCII code is less than or greater than the ASCII code of the corresponding character. Secondly and provided string2<=string1, each character of string1 is compared with the corresponding character of string3 to ensure that, for each character, string1<=string3. If both conditions are true, that is string2<=string1 and string1<=string3 are both satisfied, the function returns true, otherwise it returns false.

Example

Calculate lStatus as  chk('b',' ','c')
# returns true because b>' ' and b<c 

Calculate lStatus as  chk('B','B','C')
# returns true because B=B and B<C 

Calculate lStatus as  chk('SD04','AA00','ZZ99')
# returns true, since for each character of the respective strings, 
# it is true that SD04>AA00 and SD04<ZZ99 
# that is, S>=A, D>=A, 0>=0, 4>=0 
# and S<=Z, D<=Z, 0<=9, 4<=9 

Calculate lStatus as  chk('SDA4','AA00','ZZ99')
# returns false, since in comparing the strings, 
# SDA4 and ZZ99, the character A>9 

Calculate lStatus as  (chk('SDA4','AA00','ZZ99')+1=0+1)
# returns true