Delphi: Help needed with errors with strings and integers

Question

I need to make a 'Calculator' that works out and average for 3 different marks.

procedure TForm1.btnAddClick(Sender: TObject);
var
    sName                          : string;
    iprac, itheory, iproject       : integer;
begin
 sName := edtStudentName.text;
 iprac := sedPrac.value;
 iTheory := sedTheory.Value;
 iProject := sedProject.Value;
  lblOutput.caption := sName + ' You got ' + IntToStr (iPrac + iTheory + iProject) / 3;

end;
end.

Thats the code so far, but I get an error:

[Error] ComputerStudyMarks_u.pas(46): Incompatible types: 'String' and 'Integer'

Please be patient with me! I am a hardcore noob but this is for school. Maybe someone can help me with this program. I am busy using the book "Enjoy Delphi" and the code I am copying from the book itself is giving me an error. Any help would be much appreciated! P.S I cant add a picture of the form because I dont have enough reputation :(

David Heffernan · Accepted Answer · 2014-02-05 16:47:28Z

1

iprac := sedPrac.value;

It's not clear what sedPrac is. And therefore what the Value property it. If Value is a string then you cannot assign a string to an integer. Your would need to convert to integer first, like this:

iprac := StrToInt(sedPrac.value);

Likewise for iTheory and iProject.

Of course, it may be that Value is already an integer, in which case your code is fine. My best guess is that these variables refer to TSpinEdit controls, and that Value is an integer, and so all is well. But that is just a guess.

IntToStr (iPrac + iTheory + iProject) / 3

Now, IntToStr is a function that returns a string. And there is no / operator defined for strings. Presumably you meant to write:

IntToStr((iPrac + iTheory + iProject) div 3)

Note that you have to use div since the value is an integer and / is floating point division.

Some final pieces of advice.

When presenting code, present all the information. You omitted to present some types here and so we don't know what sedPrac is.
When you present an error message, make sure that we can marry up the line number in the message with the code that you present. In your question, we don't know which line is line 46.

edited Feb 5, 2014 at 16:47

answered Feb 5, 2014 at 16:41

David Heffernan

616k46 gold badges1.1k silver badges1.5k bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Aidan Quinn Over a year ago

Thank you!Sorry for not adding enough information. btw, sedPrac refers to s SpinEdit. Your answer is much appreciated. Also, the theory and practical marks are out of 40, and the project mark is out of 20, how would I get the value in % for all three marks?

David Heffernan Over a year ago

40+40+20=100. So you just need to add the raw results. In other words, iPrac + iTheory + iProject gives you the overall percentage mark. You might want to add some validity checking to make sure that nobody enters an out of range score.

Collectives™ on Stack Overflow

Delphi: Help needed with errors with strings and integers

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related