Change the code...
using (SqlDataAdapter da = new SqlDataAdapter(cmd))
{
da.Fill(ds);
dt = ds.Tables[0];
}
To...
DataTable dt = null;
using (SqlDataAdapter da = new SqlDataAdapter(cmd))
{
da.Fill(ds);
}
if(ds != null && ds.Tables != null && ds.Tables.Count > 0)
{
dt = ds.Tables[0];
}
Now check if
dt
is
null
or not. If not
null
, then proceed and serialize that.