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[this message has been edited by mike doty (edited july 31, 2007).]
Code:
'comments: [url="http://www.powerbasic.com/support/pbforums/showthread.php?t=22506"]http://www.powerbasic.com/support/pbforums/showthread.php?t=22506[/url]
#compile exe
#dim all
'string2long.bas
'
'purpose: 1) extract "0123456789-" from a string to create a long.
' 2) val terminates on invalid characters. this does not.
' 3) eliminate need for a string function to extract result.
' 4) fastest performance for this specific purpose.
' 5) suggestion for "optimized val for each data type" officially rejected by pb.
'val supports:
'scientific notation
'rounding of floating point values assigned to an integer
'radix
'unary operators
'overflow
'
'comments: 'add-on library, include file or dll containing assembler routines
' 'would make an excellent addition for ultimate performance.
'
'modified: 7/31/07 only updated the documention
'
'
declare function string2money(smain as string) as string
declare function string2long(smain as string) as long
'
function string2money(smain as string) as string
'make long from string, return string in money format
function = using$(",.##",string2long(smain) *.01)
end function
'
function pbmain( )
local smain as string, lresult as long
'
smain = "please pay (-) dollars 123 cents 45"
' call statements: results:
lresult = string2long(smain) '12345
? string2money(smain) '123.45
lresult = val(smain) '0
end function
'
function string2long(snum as string) as long
'
'use "012345679-" at any position to create long value
'does not terminate on invalid characters
'credits to: john gleason, paul dixon, mike trader, mike doty (me)
'http://www.powerbasic.com/support/pbforums/showthread.php?t=14373i] ;get the point to the string contents (added this)
!xor edx,edx ;the sum =0
!xor ecx,ecx ;the neg flag =0
!movzx eax,byte ptr [edi] ;get the first character
lp:
!cmp eax,"0" ;is character < a "0"?
!jl lessthan0 ;yes, skip to the non-digit check
!cmp eax,"9" ;is it greater than a "9"?
!jg nextcharacter ;yes, get next char.
'to get here it must be a digit
!imul edx,10 ;sum=sum*10 ..
!add edx,eax ; + digit
!sub edx,48 ; - 48
!jmp nextcharacter
lessthan0:
rem !cmp eax,"." ;is it a "." 'rem to terminate on decimal
rem !je done ;yes, then exit loop 'rem to terminate on decimal
!cmp eax,"-" ;is it a "-"
!jne nextcharacter ;no, get next character
!mov ecx,1 ;set the neg flag
nextcharacter:
!inc edi ;increment the string pointer
!movzx eax,byte ptr [edi] ;get next character
!or eax,eax ;test if zero
!jnz lp ;not zero, go back and do next character
done:
!cmp ecx,0 ;is neg flag set?
!je skip ;no, skip next instruction
!neg edx ;yes, negate answer
skip:
!mov function,edx ;write answer to function
end function
'
[this message has been edited by mike doty (edited july 31, 2007).]
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