I want to create a new column in a datatable from two existing columns. I
have no problem to create the new column using the datatable.colum ns.add
method. The problem is the value of the new column may become system.dbnull
since one of the two existing columns may have system.dbnull. How can I fix
it so the new column will get the value of the other column even the other
column is system.dbnull?
Sep 29 '07
13  2608 
Hi Armin,
What I mean is the value of the new column will have the combined value of
existing columns I specified using datatable.colum ns.add().
"Armin Zingler" wrote:
"Peter" <Pe***@discussi ons.microsoft.c omschrieb
Hi Armin,
I add the new column based on existing columns. If one of the based
columns contains null (dbnull), the new column will contain null
regardless the value in other based columns.
What is a "column based on existing columns"?
Armin
The value of the new column will simply be the value of columnX + the value
of columnY. This is simply done by issuing datatable.colum ns.add().
However, the value of the new column will be null if either one of the
columns is null.
"Armin Zingler" wrote:
"Peter" <Pe***@discussi ons.microsoft.c omschrieb
Hi Armin,
What I mean is the value of the new column will have the combined
value of existing columns I specified using datatable.colum ns.add().
What's a "combined value"? Sorry for asking if that's too obvious.
"Armin Zingler" wrote:
"Peter" <Pe***@discussi ons.microsoft.c omschrieb
Hi Armin,
I add the new column based on existing columns. If one of the based
columns contains null (dbnull), the new column will contain null
regardless the value in other based columns.
What is a "column based on existing columns"?
Armin
"Peter" <Pe***@discussi ons.microsoft.c omschrieb
The value of the new column will simply be the value of columnX +
the value of columnY. This is simply done by issuing
datatable.colum ns.add(). However, the value of the new column will
be null if either one of the columns is null.
Ok, but how do you calculate the values in the column? The sum must be put
into the rows at any time.
"Armin Zingler" wrote:
"Peter" <Pe***@discussi ons.microsoft.c omschrieb
Hi Armin,
>
What I mean is the value of the new column will have the
combined value of existing columns I specified using
datatable.colum ns.add().
What's a "combined value"? Sorry for asking if that's too obvious.
"Armin Zingler" wrote:
>
"Peter" <Pe***@discussi ons.microsoft.c omschrieb
Hi Armin,
>
I add the new column based on existing columns. If one of
the based columns contains null (dbnull), the new column
will contain null regardless the value in other based
columns.
What is a "column based on existing columns"?
Armin
Peter,
What Armin probably asks is. Show that piece of code that you are using. It
seems that people is afraid to show that here, why we don't understand,
because really you are not showing secrets or your own inventions with that.
We are not forever asking direct questions here in this newsgroup, however I
know that Armin often asks, "Show us a piece of your code".
:-)
Cor
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