Hi
I'm trying to call the method Contains in a loop: out of the loop I set the
primary key of the dataTable.
The method returns true one time at a certani value, but then, when the loop
steps forward to check another value, the method returns false, although the
value is contained in the dataTable (DateTime values). So the loop goes and
goes ...
Also tried with Find, but I had the same result.
Can anyone help me?
Marco 6 17431
Hi,
Can you post the code in question?
Cheers,
--
Ignacio Machin,
ignacio.machin AT dot.state.fl.us
Florida Department Of Transportation
"Millo" <mi************ **@libero.it> wrote in message
news:Gi******** *************@t wister2.libero. it... Hi
I'm trying to call the method Contains in a loop: out of the loop I set
the primary key of the dataTable.
The method returns true one time at a certani value, but then, when the
loop steps forward to check another value, the method returns false, although
the value is contained in the dataTable (DateTime values). So the loop goes
and goes ...
Also tried with Find, but I had the same result.
Can anyone help me?
Marco
Millo <mi************ **@libero.it> wrote: I'm trying to call the method Contains in a loop: out of the loop I set the primary key of the dataTable.
The method returns true one time at a certani value, but then, when the loop steps forward to check another value, the method returns false, although the value is contained in the dataTable (DateTime values). So the loop goes and goes ...
Also tried with Find, but I had the same result.
Can anyone help me?
Could you post a short but complete program which demonstrates the
problem?
See http://www.pobox.com/~skeet/csharp/complete.html for details of
what I mean by that.
--
Jon Skeet - <sk***@pobox.co m> http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
[...]
private void setPrimaryKeys( ) // in order to use the Contains method of the
dataTable
{
DataColumn[] columnPrimaryKe ys = new DataColumn[1];
columnPrimaryKe ys[0] = this.Columns["date"];
this.PrimaryKey = columnPrimaryKe ys;
}
public bool HasDate( DateTime date )
{
bool hasDate;
hasDate = this.Rows.Conta ins(date);
return hasDate;
}
public DateTime GetQuoteDateOrP receding( DateTime date )
{
if(this.HasDate (date))
{
return date;
}
else
{
return GetQuoteDateOrP receding(date.S ubtract(new
TimeSpan(1,0,0, 0)));
}
}
the problem is in the HasDate method: it works just one time: then
GetQuoteDateOrP receding continues without returning a date because the
hasDate method fails to return true (although I see with my eyes - with the
VS debugger - that the dates passed as parameters ARE in the dataTable in
the column "date").
It seems to me very absurd ... I can't understand where I'm wrong (I've been
debugging for hours, but nothing.)
Thanks in advance.
"Jon Skeet [C# MVP]" <sk***@pobox.co m> ha scritto nel messaggio
news:MP******** *************** *@msnews.micros oft.com... Millo <mi************ **@libero.it> wrote: I'm trying to call the method Contains in a loop: out of the loop I set
the primary key of the dataTable.
The method returns true one time at a certani value, but then, when the
loop steps forward to check another value, the method returns false, although
the value is contained in the dataTable (DateTime values). So the loop goes
and goes ...
Also tried with Find, but I had the same result.
Can anyone help me?
Could you post a short but complete program which demonstrates the problem?
See http://www.pobox.com/~skeet/csharp/complete.html for details of what I mean by that.
-- Jon Skeet - <sk***@pobox.co m> http://www.pobox.com/~skeet If replying to the group, please do not mail me too
Millo,
Remember that a DateTime in .NET has both Date & Time information in it.
Are you certain that the DateTime you pass to HasDate only has a date in it
and the DateTimes in your datatables only have dates in them?
In other words, you don't have time floating around in any of your DateTime
objects? As Time (specifically fractions of milliseconds) would make
matching significantly more difficult...
I would probably add -1 days to the date instead return GetQuoteDateOrP receding(date.S ubtract(new TimeSpan(1,0,0, 0)));
return GetQuoteDateOrP receding(date.A ddDays(-1));
Hope this helps
Jay
"Millo" <mi************ **@libero.it> wrote in message
news:ss******** *************@t wister1.libero. it... [...]
private void setPrimaryKeys( ) // in order to use the Contains method of
the dataTable { DataColumn[] columnPrimaryKe ys = new DataColumn[1]; columnPrimaryKe ys[0] = this.Columns["date"]; this.PrimaryKey = columnPrimaryKe ys; }
public bool HasDate( DateTime date ) { bool hasDate; hasDate = this.Rows.Conta ins(date); return hasDate; }
public DateTime GetQuoteDateOrP receding( DateTime date ) { if(this.HasDate (date)) { return date; } else { return GetQuoteDateOrP receding(date.S ubtract(new TimeSpan(1,0,0, 0))); } } the problem is in the HasDate method: it works just one time: then GetQuoteDateOrP receding continues without returning a date because the hasDate method fails to return true (although I see with my eyes - with
the VS debugger - that the dates passed as parameters ARE in the dataTable in the column "date"). It seems to me very absurd ... I can't understand where I'm wrong (I've
been debugging for hours, but nothing.)
Thanks in advance.
"Jon Skeet [C# MVP]" <sk***@pobox.co m> ha scritto nel messaggio news:MP******** *************** *@msnews.micros oft.com... Millo <mi************ **@libero.it> wrote: I'm trying to call the method Contains in a loop: out of the loop I
set the primary key of the dataTable.
The method returns true one time at a certani value, but then, when
the loop steps forward to check another value, the method returns false,
although the value is contained in the dataTable (DateTime values). So the loop
goes and goes ...
Also tried with Find, but I had the same result.
Can anyone help me?
Could you post a short but complete program which demonstrates the problem?
See http://www.pobox.com/~skeet/csharp/complete.html for details of what I mean by that.
-- Jon Skeet - <sk***@pobox.co m> http://www.pobox.com/~skeet If replying to the group, please do not mail me too
Millo <mi************ **@libero.it> wrote: [...]
private void setPrimaryKeys( ) // in order to use the Contains method of the dataTable
This isn't a complete program. Please read the link I posted before.
--
Jon Skeet - <sk***@pobox.co m> http://www.pobox.com/~skeet
If replying to the group, please do not mail me too
Jay,
thank you for your tips.
In my DataTable I had only dates: but not in the parameters I passed to the
HasDate(date) method.
using: <<this.Rows.Con tains(date.Date )>> and not simply
<<this.Rows.Con tains(date)>> in this method, I made it work properly.
"Jay B. Harlow [MVP - Outlook]" <Ja************ @msn.com> ha scritto nel
messaggio news:e6******** ******@TK2MSFTN GP11.phx.gbl... Millo, Remember that a DateTime in .NET has both Date & Time information in it.
Are you certain that the DateTime you pass to HasDate only has a date in
it and the DateTimes in your datatables only have dates in them?
In other words, you don't have time floating around in any of your
DateTime objects? As Time (specifically fractions of milliseconds) would make matching significantly more difficult...
I would probably add -1 days to the date instead return GetQuoteDateOrP receding(date.S ubtract(new TimeSpan(1,0,0, 0)));
return GetQuoteDateOrP receding(date.A ddDays(-1));
Hope this helps Jay
"Millo" <mi************ **@libero.it> wrote in message news:ss******** *************@t wister1.libero. it... [...]
private void setPrimaryKeys( ) // in order to use the Contains method of the dataTable { DataColumn[] columnPrimaryKe ys = new DataColumn[1]; columnPrimaryKe ys[0] = this.Columns["date"]; this.PrimaryKey = columnPrimaryKe ys; }
public bool HasDate( DateTime date ) { bool hasDate; hasDate = this.Rows.Conta ins(date); return hasDate; }
public DateTime GetQuoteDateOrP receding( DateTime date ) { if(this.HasDate (date)) { return date; } else { return GetQuoteDateOrP receding(date.S ubtract(new TimeSpan(1,0,0, 0))); } } the problem is in the HasDate method: it works just one time: then GetQuoteDateOrP receding continues without returning a date because the hasDate method fails to return true (although I see with my eyes - with the VS debugger - that the dates passed as parameters ARE in the dataTable
in the column "date"). It seems to me very absurd ... I can't understand where I'm wrong (I've been debugging for hours, but nothing.)
Thanks in advance.
"Jon Skeet [C# MVP]" <sk***@pobox.co m> ha scritto nel messaggio news:MP******** *************** *@msnews.micros oft.com... Millo <mi************ **@libero.it> wrote: > I'm trying to call the method Contains in a loop: out of the loop I set the > primary key of the dataTable. > > The method returns true one time at a certani value, but then, when the loop > steps forward to check another value, the method returns false, although the > value is contained in the dataTable (DateTime values). So the loop goes and > goes ... > > Also tried with Find, but I had the same result. > > Can anyone help me?
Could you post a short but complete program which demonstrates the problem?
See http://www.pobox.com/~skeet/csharp/complete.html for details of what I mean by that.
-- Jon Skeet - <sk***@pobox.co m> http://www.pobox.com/~skeet If replying to the group, please do not mail me too
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