Re: SQLClient SQLAdapter Data type problem

rj wrote:
I'm having problems simply retrieving values from the database and
using in their original format. Example below assumes that size
column is double or float
Here is code snippet:

string maxSize;
string source = "Data Source=server_name; Initial Catalog=testing;
User ID=bj; Password=pass";
SqlConnection conn = new SqlConnection(source);
string select = "select max(size) from sizes";
SqlAdapter da new SqlAdapter(select, conn);
DataSet ds = new DataSet();
da.Fill(ds, "maxSize");

foreach(DataRow in ds.Tables["maxSize"].Rows)
{

maxSize = row[0].ToString();
}

Everything works here but how I go about it if I need maxSize to be
double or float? if I do maxSize = (double)row[0]; I get "cannot
explicitly convert object to double" There is something I don't quite
understand. And if query returns only one row, how can I get the size
value without using foreach?


There was no way for you to know it (except maybe by browsing through some
of the previous questions in this newsgroup before posting yours - always a
recommended practice) , but this is a classic ADO newsgroup. ADO.Net bears
very little resemblance to classic ADO so, while you may be lucky enough to
find a dotnet-knowledgeable person here who can answer your question, you
can eliminate the luck factor by posting your question to a group where
those dotnet-knowledgeable people hang out. I suggest
microsoft.public.dotnet.framework.adonet.

Having said that, I'm not sure why you are using a dataset for this purpose.
Use a SQLCommand and SQLDataReader. The ExecuteReader method has an argument
to allow you to specify that the query is returning a single row.

As to maxSize, I'm not sure why you need to convert the value to double in
order to store it in a string variable.
What are you trying to accomplish?



--
Microsoft MVP - ASP/ASP.NET
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"NO SPAM"


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