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    String/float functions in DLL


    I am using some functions in a DLL I wrote to create some strings from a line of text. I need to convert some of these strings to float(real) within a function. Can someone expalin to me how?

    Code:
    Function LenOfCallHr (S: String): String; stdcall;
    Begin
    Result := copy(S,37,2);
    end;
    
    Function LenOfCallMin (S: String): String; stdcall;
    Begin
    Result := copy(S,40,2);
    end;
    
    Function LenOfCallSec (S: String): String; stdcall;
    Begin
    Result := copy(S,43,2);
    end;
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    Can I get away with doing something like.
    Code:
    Function LenOfCall (S: String): Real; stdcall;
    Begin
    Result := ((StrToFloat(copy(S,37,2))*60)+(StrToFloat(copy(S,40,2)))+((StrToFloat(copy(S,40,2)) DIV 60));
    end;
    Last edited by lloydie-t; January 4th, 2004 at 10:31 AM.
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    Looks like it should work, provided you're extracting the right substrings of course .

    One thing to remember is that if you're calling this DLL from an application written in another programming language, their idea of a float/real type may be different from what Delphi uses (i.e. number of bytes used for the variable, precision etc.), so you may not be able to use it with other languages.
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    Wrong sort of division for real type / not DIV

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