C# Discussion Boards - CodeProject

I have the following code:

double numdaysPercentage;
numdaysPercentage = 14/30;

I get an answer like 0.0. I should get an answer like .4666667

Can someone tell me what I am doing wrong.

If you divide by an int, you get an int.

double n = 14/30.0;

will work

or

double n = 14/(double)30;

Christian Graus

Please read this if you don't understand the answer I've given you

"also I don't think "TranslateOneToTwoBillion OneHundredAndFortySevenMillion FourHundredAndEightyThreeThousand SixHundredAndFortySeven()" is a very good choice for a function name" - SpacixOne ( offering help to someone who really needed it ) ( spaces added for the benefit of people running at < 1280x1024 )

You are doing integer division, and 14/30 is indeed 0. On the other hand, 14.0/30 will give you what you are looking for.

Cheers,
Vikram.

The hands that help are holier than the lips that pray.

The suggestions above are good, you can also tag the numbers with an 'd' to indicate they are doubles. (Or 'f' for floats)

double n = 14d / 30d;

Simon

hello,
im having problem with the conversion from string to float, it works good when there is no character in string, for example :
string a = "1.22235647228796";
string b = "8.742277657e-008";

float a = Convert.ToSingle(a);
float b = Convert.ToSingle(b);

the first conversion will work but second will give error that "string was not is correct format"

any idea to solve it ?
thanks

TVMU^P[[IGIOQHG^JSH`A#@`RFJ\c^JPL>;"[,*/|+&WLEZGc`AFXc!L
%^]*IRXD#@GKCQ`R\^SF_WcHbORY87??6?N8?BcRAV\Z^&SU~%CSWQ@#2
W_AD`EPABIKRDFVS)EVLQK)JKSQXUFYK[M`UKs*$GwU#(QDXBER@CBN%
Rs0~53%eYrd8mt^7Z6]iTF+(EWfJ9zaK-i?TV.C\y<p?jxsg-b$f4ia>
--------------------------------------------------------
128 bit encrypted signature, crack if you can

Always use float.TryParse for a start, so you don't get an exception. Not sure how you specify to accept that format, tho.

Christian Graus

Please read this if you don't understand the answer I've given you

"also I don't think "TranslateOneToTwoBillion OneHundredAndFortySevenMillion FourHundredAndEightyThreeThousand SixHundredAndFortySeven()" is a very good choice for a function name" - SpacixOne ( offering help to someone who really needed it ) ( spaces added for the benefit of people running at < 1280x1024 )

Christian Graus wrote:
Always use float.TryParse for a start

Not always. Sometimes an exception, due to a missed return value check, is in order. I would prefer an exception in certain instances.

Pits fall into Chuck Norris.

i didnt specify, when i read single from a file it automatically came, eg

BR.ReadSingle()

TVMU^P[[IGIOQHG^JSH`A#@`RFJ\c^JPL>;"[,*/|+&WLEZGc`AFXc!L
%^]*IRXD#@GKCQ`R\^SF_WcHbORY87??6?N8?BcRAV\Z^&SU~%CSWQ@#2
W_AD`EPABIKRDFVS)EVLQK)JKSQXUFYK[M`UKs*$GwU#(QDXBER@CBN%
Rs0~53%eYrd8mt^7Z6]iTF+(EWfJ9zaK-i?TV.C\y<p?jxsg-b$f4ia>
--------------------------------------------------------
128 bit encrypted signature, crack if you can

Try using the NumberStyles enum in the System.Globalization namespace to parse that text.

float b = float.Parse(ExpNumString, NumberStyles.AllowExponent|NumberStyles.Float);

Hi all,

In my app i have 1 class call sqlconnection which is use for get/update db data. I am use this class to get dataset and after i edit the dataset i will pass back to this class and update it.Example, call sqlconnection method from formA to get and update database:

class sqlconnection:

private OleDbConnection objConn;<br />
  private OleDbDataAdapter objAdapter = new OleDbDataAdapter();<br />
<br />
  public void DbConnection()<br />
  {<br />
    objConn = new OleDbConnection(@"Provider=Microsoft.Jet.OLEDB.4.0;DataSource=Userprogram.mdb");<br />
  }<br />
<br />
  public DataSet SelectSQL(String stable,String sProgramName)<br />
  {<br />
    DataSet ds=new DataSet();<br />
    objConn.Open();<br />
    objCmdSelecte = new OleDbCommand("Select * From Timeway where TW_Program_Name ='" +  sProgramName + "'", objConn);<br />
                <br />
    objAdapter.SelectCommand = objCmdSelecte;<br />
    objAdapter.Fill(ds);<br />
    objConn.Close();<br />
    return ds;<br />
   }<br />
<br />
   public void UpdateSQL(DataSet ds)<br />
   {<br />
     objConn.Open();<br />
     objAdapter.Update(ds);<br />
     objConn.Close();<br />
   }

formA:

sqlconn.DbConnection();<br />
   ds = sqlconn.SelectSQL("PS", "Program Ni");<br />
      for (int i = 0; i < 16;i++ )<br />
        {<br />
            ArrayData[i] = ArrayTextbox[i].Text;     //insert modified value<br />
            ds.Tables[0].Rows[0][i + 1] = ArrayData[i];<br />
        }<br />
      ds.AcceptChanges();<br />
      sqlconn.UpdateSQL(ds);

The problem i am facing is , nothing change to my database.I have already check the dataset which is pass to my sqlconnection class and it have been modified. So what i guess is the problem of objAdapter.update. Can anyone guide me to solve this problem? Confused | :confused:

thanks in advance
cocoon

Hi all,

Thank you for those who are read through my question. I have found the solution , very simple, that is add a tablemapping.add() before fill and acceptchanges() and the end when update record.

regard
cocoon

Hello All,

How to compare two enum types?

Thanks

If you need to, then you should probably use the one enum in both cases.

you have two options:

1 - cast both to int, if you can make the int values correlate ( but then just use the one enum )
2 - write a method that applies whatever comparison rules you need, by hand.

Christian Graus

Please read this if you don't understand the answer I've given you

"also I don't think "TranslateOneToTwoBillion OneHundredAndFortySevenMillion FourHundredAndEightyThreeThousand SixHundredAndFortySeven()" is a very good choice for a function name" - SpacixOne ( offering help to someone who really needed it ) ( spaces added for the benefit of people running at < 1280x1024 )

use the typeof(ur enum) with compare() method

Cheers,Earn and Enjoy
RRave
MCTS,MCPD
http://ravesoft.blogspot.com

How would that work, exactly ?

Christian Graus

Please read this if you don't understand the answer I've given you

"also I don't think "TranslateOneToTwoBillion OneHundredAndFortySevenMillion FourHundredAndEightyThreeThousand SixHundredAndFortySeven()" is a very good choice for a function name" - SpacixOne ( offering help to someone who really needed it ) ( spaces added for the benefit of people running at < 1280x1024 )

Good question

i have put small exmaple here

public enum Named : int
{
A,
B,
C,
D
}
public enum Names : byte
{
A,
B,
C,
D

}

check
if (Enum.Equals(typeof(Named),typeof(Names)))
{
//type is equal
}

thanks you

Cheers,Earn and Enjoy
RRave
MCTS,MCPD
http://ravesoft.blogspot.com

OK - so does that compare based on enum name, or their intrinsic int value ?

Christian Graus

Please read this if you don't understand the answer I've given you

"also I don't think "TranslateOneToTwoBillion OneHundredAndFortySevenMillion FourHundredAndEightyThreeThousand SixHundredAndFortySeven()" is a very good choice for a function name" - SpacixOne ( offering help to someone who really needed it ) ( spaces added for the benefit of people running at < 1280x1024 )

I seen your profile,your are MVP in code project, Are you checking me? Big Grin | :-D

Basically Compare based on the type of the enum

You can understand from my example.

Thank you

Cheers,Earn and Enjoy
RRave
MCTS,MCPD
http://ravesoft.blogspot.com

No, I've never seen this before, I would think that comparing two different enums is a bad design, I'm curious how it would work.

Christian Graus

Please read this if you don't understand the answer I've given you

"also I don't think "TranslateOneToTwoBillion OneHundredAndFortySevenMillion FourHundredAndEightyThreeThousand SixHundredAndFortySeven()" is a very good choice for a function name" - SpacixOne ( offering help to someone who really needed it ) ( spaces added for the benefit of people running at < 1280x1024 )

So
is it wrong? or is it can't be exist like that?

Cheers,Earn and Enjoy
RRave
MCTS,MCPD
http://ravesoft.blogspot.com

I am saying I've never used it, I was curious how it works, although I'd never use it, personally.

Christian Graus

Please read this if you don't understand the answer I've given you

"also I don't think "TranslateOneToTwoBillion OneHundredAndFortySevenMillion FourHundredAndEightyThreeThousand SixHundredAndFortySeven()" is a very good choice for a function name" - SpacixOne ( offering help to someone who really needed it ) ( spaces added for the benefit of people running at < 1280x1024 )

Thank you.

Cheers,Earn and Enjoy
RRave
MCTS,MCPD
http://ravesoft.blogspot.com

You're trying to compare the types to each other. The enum Equals takes two enum values.

www.wickedorange.com
www.andrewvos.com

*The enum Equals can take two enum values

www.wickedorange.com
www.andrewvos.com

Since I haven't tried this before, are there any major problems with launching an external process from a BackgroundWorker thread?
Just thought I'd ask before I try and start pulling what little hair I have left.

Thanks in advance,
Steve.