FotS

The Split() function cuts a string at specific points, returning the resultant sub-strings in an array and returns the highest dimension of the array.

The elements of the array are the delimited sub-strings of the input string. e.g.

x=Split("fred,jim,sheila",",")

will break the string at each

","

return x=3 and the three sub-strings

"fred"

,

"jim"

&

"sheila"

in elements 1,2 & 3 of the string array.

<li>The sub-strings are always returned in the array

SP$

. It is not currently possible to specify another Array.</li> <li>Split() trashes the passed-in string - if this is a problem consider this method.</li> <li>If no delimiter is found, Split() returns 1 - with

SP$(1)

as the entire string.</li> <li>Sub-strings are not trimmed in any way.</li> <li>The delimiter can be any length>0. Performing the Split() on the above string, specifying

"jim"

as the delimiter would return two elements

"fred,"

and

",sheila"

.</li> <li>The delimiter does not form any part of the sub-strings.</li>

Compatible with all versions of MMBasic.

Syntax:

  NumOfElements=Split(StringToSplit, delimeter)

Example usage:

	z=Split(Time$,":")
        FOR n=1 TO z
            PRINT n,SP$(n)
        NEXT

The Code:

 Function Split(a$,b$) As Integer' returns the number of dimensions in SP$ always starts from 1 regardless of OPTION BASE
    Local Integer z,n,m
    If b$="" Then Split=0:Exit Function ' can't split with an empty delimiter

    ' if SP$ doesn't exist, the ERASE will cause an error, choose which ON ERROR SKIP you need 

'MM.Ver <5.04
    On Error Skip    
'MM.Ver >=5.04
    On Error Skip 1

    Erase SP$
    z=1:n=0
    Do 'count instances of delimiter for DIM SP$()
      z=Instr(z,a$,b$)
      If z=0 Then
        If n=0 Then ' no delimeters
          Dim SP$(1):SP$(1)=a$:Split=1:Exit Function ' only one substring
        Else          
          Exit Do
        End If
      Else
        n=n+1:z=z+Len(b$)
      End If
    Loop

    m=n+1:n=1
    Dim SP$(m)
    Do 
      z=Instr(1,a$,b$)
      If z=0 Then 
        SP$(m)=a$:Exit Do
      Else
        SP$(n)=Left$(a$,z-1):a$=Mid$(a$,z+Len(b$)):n=n+1
      End If
    Loop
    Split=m
  End Function

The cField$ CFunction extracts individual fields from a string in real-time rather than splitting and you might consider this as it offers advantages of speed and memory over Split() but has some limitations in that an empty string is returned if the delimiter is not found and there is no way of telling the number of substrings.

UBound() Function