Question

I am using a DataTable which has a total column within it which adds all the the columns up to give a final value. But I need to make it so if the total is over a limit it will give a message like “You have gone over what you are allowed”.
so it would look something like this

if(dt.Column("Total") > 30)
{
   //Display message in label
}

Answer 1

You can use the “old” DataTable.Compute method with a columns expression, for example:

int total = (int) dt.Compute("SUM(Total)", null); // the second argument is the filter
if(total > 30)
{
     LblMessage.Text = "Total value exceeded maximum of 30!";
}

Here’s the “modern” Linq approach:

int total = dt.AsEnumerable().Sum(r => r.Field<int>("Total"));
// ...