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Hi,
Here's some code that fully explains how I am obviously missing something that everyone else seems to understand but me:
private decimal getBalanceOH(DateTime fDate)<br />
{<br />
MessageBox.Show("fDate passed to getBalanceOH is " + fDate);<br />
decimal BalanceOH = 0;<br />
string reportDate = fDate.ToString("MM/dd/yyyy");<br />
DataTable table = myclubDataSet.Tables["TresReports"];<br />
string expression;<br />
expression = "ReportDate = #" + reportDate + "#";<br />
DataRow[] rows = table.Select(expression);<br />
if (rows.Length == 0)<br />
{<br />
MessageBox.Show("Could not find the information sought");<br />
}<br />
else<br />
{<br />
for (int i = 0; i < rows.Length; i++)<br />
{<br />
<br />
<br />
BalanceOH = Convert.ToDecimal(myclubDataSet.Tables["TresReports"].Rows[i]["BalanceOH"]);<br />
MessageBox.Show("BalanceOH to sent to results :" + BalanceOH);<br />
DateTime repDate = Convert.ToDateTime(myclubDataSet.Tables["TresReports"].Rows[i]["ReportDate"]);<br />
<br />
if (repDate != fDate)<br />
{<br />
MessageBox.Show("I dunno what I'm doing");<br />
} <br />
<br />
return BalanceOH;<br />
}<br />
}<br />
MessageBox.Show("Error");<br />
return BalanceOH;<br />
}
It comes up "I dunno what I'm doing" all the time.
I have read that many articles and messages that it has become clear to me that I MUST be missing something.
I would greatly appreciate anyones input.
Thank you.
-- modified at 5:50 Wednesday 16th August, 2006
Glen Harvy
Very, very frustrated at the moment
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Glen Harvy wrote: BalanceOH = Convert.ToDecimal(myclubDataSet.Tables["TresReports"].Rows[i]["BalanceOH"]);
BalanceOH = decimal.Parse(myclubDataSet.Tables["TresReports"].Rows[i]["BalanceOH"].ToString());
Glen Harvy wrote: DateTime repDate = Convert.ToDateTime(myclubDataSet.Tables["TresReports"].Rows[i]["ReportDate"]);
System.IFormatProvider FormaT = new System.Globalization.CultureInfo("sq-AL", true);<br />
DateTime repDate = DateTime.ParseExact(myclubDataSet.Tables["TresReports"].Rows[i]["ReportDate"].ToString(), "yyyy-MM-dd", FormaT );
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I can pass any date I like - if it is a valid ReportDate then the program runs without error BUT always returns the value of Row 0 no matter what. The problem is that I can't figure out how to get the proper row to return.
Glen Harvy
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I think the problem is here
<br />
DateTime repDate = Convert.ToDateTime(myclubDataSet.Tables["TresReports"].Rows[i]["ReportDate"]);<br />
<br />
if (repDate != fDate)<br />
{<br />
MessageBox.Show("I dunno what I'm doing");<br />
} <br />
the fDate may contains hh:mm:ss value, but the repDate is 00:00:00.
e.g
<br />
fDate = DateTime.Now;
repDate = Convert.ToDateTime("2006/08/16");
and 2006/08/16 18:14:05 != 2006/08/16 00:00:00
so you will always get "I dunno what I'm doing" all the time.
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WuJunyin wrote: so you will always get "I dunno what I'm doing" all the time.
There's a problem with the programming logic not the date formats.
I am NOT getting the Row I am looking for returned and I don't know how to do that?
Glen Harvy
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I'm guessing that maybe the values are the same, but the objects are not.
I'm not sure how the == operator compares the DateTimes, but it could be that the culture eg. (or something else) is different. Maybe you can print out the values of several properties and compare them.
godd luck.
I've found a living worth working for, but I haven't found work worth living for.
<marquee> ![Beer | [beer]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/beer.gif) ![Jig | [Dance]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/jig.gif)
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As DateTime is a value type, the == operator will be comparing the values, not the objects.
The actual values that will be compared is the value of the Ticks property. A tick is 100 nanoseconds, so the values have to be exactly the same to be equal. If they are off by 0.0000001 seconds, they are not equal.
---
b { font-weight: normal; }
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Guffa wrote: As DateTime is a value type, the == operator will be comparing the values, not the objects
you're probably right
Guffa wrote: The actual values that will be compared is the value of the Ticks property. A tick is 100 nanoseconds, so the values have to be exactly the same to be equal. If they are off by 0.0000001 seconds, they are not equal
this, I knew
tnx
I've found a living worth working for, but I haven't found work worth living for.
<marquee>
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A. The ReportDate is passed to the select statement.
B. The select statement supposedly retrieves all rows equalling that value.
C. The select statement returns the value contained in the ReportDate AND the BalanceOH fields.
D. Irrespective of what date I pass to the select statement, it always retieves row 0, etc AND the comparative statement is only there for cosmetic and confirmation of B. not returning the correct BalanceOH figure.
E. The value of BalanceOH is not the balance corresponding to the date I want.
F. The comparison is only made to confirm to me that I don't know what I'm doing.
If there was a problem with the formatting of the dates, then I don't see why the select statement is retrieving any rows at all.
What I think is wrong is that I am always going to get the value 0 returned becuase that is what the value of i is. Shouldn't I be passing the value of the row number corresponding to the selected ReportDate of the datatable?
BalanceOH = Convert.ToDecimal(myclubDataSet.Tables["TresReports"].Rows[i]["BalanceOH"]);
Glen Harvy
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Glen Harvy wrote: If there was a problem with the formatting of the dates, then I don't see why the select statement is retrieving any rows at all.
Actually I'm not talking about the formatting.
What I thought was that the culture retrieved from the database was eg. EN-us while the culture you are working with was Neutral. Furthermore, according to Guffa, the "==" operator should only check the values. In that case I was wrong.
How many rows do you retrieve? Isn't there a possibility to step into the code?
Also, as mentioned above by Guffa, one thick difference is a difference.
You could check eg. on year, month, and day instead of the entire DateTime object.
The problem probably lies in a very small corner.
Glen Harvy wrote: What I think is wrong is that I am always going to get the value 0 returned becuase that is what the value of i is. Shouldn't I be passing the value of the row number corresponding to the selected ReportDate of the datatable?
BalanceOH = Convert.ToDecimal(myclubDataSet.Tables["TresReports"].Rows[i]["BalanceOH"]);
I'm not sure what you mean by this, but a DataSet is just like a the view you get when executing a select statement. What you can do is execute the select statement in the database itself. That view should exactly be the contents of your DataSet. If you iterate through it with a for loop you should get each row of that view.
Good luck.
I've found a living worth working for, but I haven't found work worth living for.
<marquee>
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If any body call URLDownloadToFile using c#.net in web application,
what are the parameters that i shall pass.
Bibhu
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Hi. i am still new on C#.i am trying to display data on the texboxes from database using classes but it doesn't display any data where as is there here is my class.
public void SeachCustomer(string CName,string CNum)
{
CustomerName = CName;
Barcode1 = CNum;
SqlConnection conn = new SqlConnection();
conn.ConnectionString = "integrated security=SSPI;initial catalog=Phusa;server = za211149;persist security info=False";
conn.Open();
try
{
SqlCommand cmdSearch = new SqlCommand();
cmdSearch.Connection = conn;
cmdSearch.CommandText = "SELECT CustomerName FROM Events WHERE Barcode1 =@Barcode1";
SqlParameter Bar = new SqlParameter();
Bar.ParameterName = "@Barcode1";
Bar.Direction = System.Data.ParameterDirection.Output;
Bar.Value = Barcode1;
cmdSearch.Parameters.Add(Bar);
SqlParameter Nam = new SqlParameter();
Nam.ParameterName="@CustomerName";
Nam.Direction = System.Data.ParameterDirection.Output;
Nam.Value =CustomerName;
cmdSearch.Parameters.Add(Nam);
SqlDataReader dr =cmdSearch.ExecuteReader();
while(dr.Read()==true)
{
CustomerName = dr["CustomerName"].ToString();
}
}
catch(Exception ex)
{
MessageBox.Show(ex.Message);
}
finally
{
conn.Close();
}
-- modified at 4:02 Wednesday 16th August, 2006
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Hi,
First of all you haven't added the 'Bar' parameter.
Mamphekgo wrote: cmdSearch.Parameters.Add(Nam);
As shown above only the 'Nam' param is added.
Mamphekgo wrote: i am trying to display data on the texboxes from database
You have not written any code to display the data ?
Another problem is that CustomerName will only contain the last row's data , bcoz u r not concatenating the strings..
Mamphekgo wrote: CustomerName = dr["CustomerName"].ToString();
Try to provide complete code if you have missed something or try to correct the above said errors and check for the desired result.
"A good programmer is someone who looks both ways before crossing a one-way street." -- Doug Linder
Anant Y. Kulkarni
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actually my code can see that there is data on the database because when i use messagebox to search if ever there is something ot the database it shows that it found the record.but data cannot display on the texboxes,here i am trying to call my class to display data.
SearchCustomers search = new SearchCustomers();
string Barcode1;
string CustomerName ="";
string Barcode;
string ProductName="";
string Price = "";
if(txtBarcode.Text.Length <4)
{
Barcode1 =txtBarcode.Text;
CustomerName = lblCustomerName.Text;
search.SeachCustomer(CustomerName,Barcode1);
}
else
{
Barcode = txtBarcode.Text;
lblProductName.Text = ProductName;
lblPrice.Text =Price.ToString();
search.SeachProduct(Barcode,ProductName,Price);
}
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Hi,
Sorry, I didnt got you still. Since you are using the SearchCustomer function to search the db, but it dosent returns any value ?
Mamphekgo wrote: search.SeachCustomer(CustomerName,Barcode1);
Mamphekgo wrote: when i use messagebox to search
I didnt understand where you are applying this message box ? Inside SearchCustomer or where you are using the object. Sorry but i can see only one problem that ur SearchCustomer function should return the Customer name which you will then set in any text box or other controls.
Hope i am guessing it right ! 
"A good programmer is someone who looks both ways before crossing a one-way street." -- Doug Linder
Anant Y. Kulkarni
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the sample code is here: (in .NET Framework 2.0)
<br />
object obj = "abc";<br />
string s2 = obj as string;
string s3 = (string)obj;
string s4 = obj.ToString();
thanks in advance
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If you know that the object contains a string:
string s3 = (string)obj; // method 2
If the object may contain other types of data:
string s2 = obj as string; // method 1
The s2 variable will be null if the object did not contain a string.
If you want a string value whatever the object contains:
string s4 = obj.ToString(); // method 3
The s4 variable will contain the string representation of whatever the object contains. If the object for an example contain an integer with the value 42, you will get the string value "42".
---
b { font-weight: normal; }
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I always use this method to get the string, because I can sure its type is string.
<br />
string s3 = (string)obj;
if the obj is not a string, then it would occur a exception.
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An implicit cast is safer that using 'as', but I am lazy, so I prefer to use 'as'
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<br />
object a = 123;<br />
<br />
try {<br />
string s1 = (string)a;<br />
Console.WriteLine("method 1 value: {0}", s1);<br />
}<br />
catch {<br />
Console.WriteLine("method 1 error.");<br />
}<br />
<br />
try {<br />
string s1 = a as string;<br />
Console.WriteLine("method 2 value: {0}", s1);<br />
}<br />
catch {<br />
Console.WriteLine("method 2 error.");<br />
}<br />
<br />
method 1 error. <br />
method 2 value:
use 'as' can replace try-catch block. haha...
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leppie wrote: An implicit cast is safer that using 'as', but I am lazy, so I prefer to use 'as'
Implicit cast? Don't you mean an explicit cast?
If you use a cast, you will get the exception at the instruction trying to do the cast. If you use "as", you will get a null reference exception somewhere else in the code, when you try to use the reference from the failed cast. Or even worse, it will silently store the value somewhere, and you get the error message weeks later when someone tries to use the stored value...
I always try to write code so that the exception occurs where the error is, then it's a lot easier to locate the source of the error.
---
b { font-weight: normal; }
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Guffa wrote: Implicit cast? Don't you mean an explicit cast?
Hehe, yes 
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First:
I'm a fan of strong typed programming (that i think it will prevent many kind of bugs )
So I recommand using string obj="abc";
Second:
But there are times that you should use weak types
then I prefer obj.ToString();
because that one day may be I want to pass another type of object to my method
for example:
object obj=new User();
then my code will not crash but there is one thing that I shoule be aware of :NULL Reference !!! (if obj is null my colde will crash either way)
Then we can a NullSafe static method somewhere in our code
<br />
public static string GetNullSafeString(object obj)<br />
{<br />
return (obj==null?null:obj.ToString());<br />
}<br />
This way I will take advantages of polymorphism (object.ToString() ) and be sure that nothing can harm my code.
Regards
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agree with you about your first point. I know it from a book code complete (2nd)
beatles1692 wrote: First:
I'm a fan of strong typed programming (that i think it will prevent many kind of bugs )
So I recommand using string obj="abc";
P.S the reason I use object obj="abc"; above is to explain my question.
-- modified at 6:01 Wednesday 16th August, 2006
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thanks to all of you. so kind guys.
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