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C# How to add one to a cell in a Dataset?

this is the importent part of my code
DataSet HexDS = new DataSet();
DataTable HexTable = HexDS.Tables.Add();
HexTable.Columns.Add("ID", typeof(double));
HexTable.Columns.Add("Answer", typeof(double));
HexTable.Rows.Add(x, 1);
y++;
if (y >=1)
{
here i want to add one to the row with ID x(wich canbe any number because of the code i used before the piece i show you now)in the collumn Answer
}
i dont know the index too because this will be repeating with different x en y values in the same session
my question is how can i do this?

Jelte12345 Thursday, October 01, 2009 10:51 AM

Hi,

Sorry for some little syntax mistakes

Here is the working code.

DataRow[] drArr = HexTable.Select("Id=" + x);//+ was missing

drArr[0][

"Answer"]=Convert.ToDouble(drArr[0]["Answer"])+1; //selecting the rows is not necessary again

Marked As Answer byJelte12345 Thursday, October 01, 2009 7:47 PM

Tamer Oz Thursday, October 01, 2009 4:10 PM

I think this is what you are looking for.

DataRow[] drArr=HexTable.Select("Id=" x);//select the rows with Id =x
drArr[0]["Answer"]=Convert.ToDouble(HexTable.Select("Id=" x)[0]["Answer"])+1//assign the value back to Answer column of the first row by increasing 1

Unmarked As Answer byJelte12345 Thursday, October 01, 2009 3:14 PM
Marked As Answer byJelte12345 Thursday, October 01, 2009 12:12 PM

Tamer Oz Thursday, October 01, 2009 11:08 AM

so i don't have to say that the HexTable is part of the HexDS Dataset?

Jelte12345 Thursday, October 01, 2009 12:16 PM

No. It is associated when you declare.

Tamer Oz Thursday, October 01, 2009 12:23 PM

I think this is what you are looking for.

DataRow[] drArr=HexTable.Select("Id=" x);//select the rows with Id =x
drArr[0]["Answer"]=Convert.ToDouble(HexTable.Select("Id=" x)[0]["Answer"])+1//assign the value back to Answer column of the first row by increasing 1

when i copy paste this code and change Id in ID and change x into the variable i want it to be i get two errors:

the things wich are big was the error line under

DataRow[] drArr=HexTable.Select("Id=" x);

there it says : ") expected" i realy don't understand why he is saying that so i guess there is actually something else wrong

drArr[0]["Answer"]=Convert.ToDouble(HexTable.Select("Id=" x)[0]["Answer"])+1;

here it says: "Only assignment, call, increment, decrement, and new object expressions can be used as a statement" i also don't understand this one so could anyone please tell me if there is something wrong with the piece of code Tamer Oz gave me?

and i don't know if this is important but i'm using Visual C# 2008 Express edition

Jelte12345 Thursday, October 01, 2009 3:13 PM

Hi,

Sorry for some little syntax mistakes

Here is the working code.

DataRow[] drArr = HexTable.Select("Id=" + x);//+ was missing

drArr[0][

"Answer"]=Convert.ToDouble(drArr[0]["Answer"])+1; //selecting the rows is not necessary again