Gridview Totals per Row

Trying to do something which should be fairly straight forward but racking my brains in trying to get it working. Essentially all i want to do is have a calculated column in a gridview which would be based on two values from the same row.

i.e. a Unit_Cost(money) and a rate(nvarchar(20)) column are bound to the DB but i want a Total cost to be made as a calculation from the 2. I'm using a BLL to retrieve the data from my DAL and believe this code should work - but it dont :(

 protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
            CropManagementDAL.TBL_RunRow run = (CropManagementDAL.TBL_RunRow)
                ((System.Data.DataRowView)e.Row.DataItem).Row;
            if (!run.IsUnit_costNull())
            {
                if (!run.IsRateNull())
                {
                    _totalUnitPrice = run.Unit_cost * Convert.ToInt16(run.Rate);
开发者_Python百科                    e.Row.Cells[5].Text = _totalUnitPrice.ToString();
                }
            }
        }
    }

I get an error of "Input string was not in a correct format." and it highlights to my _totalUnitPrice = ... part of my code. I'm sure it's an easy one for one of you and your help is greatly appreciated!

If _totalUnitPrice is a string, you need to convert the numeric value to a string before you pass it in.

One way to do that is this:

 _totalUnitPrice = (run.Unit_cost * Convert.ToInt16(run.Rate)).ToString();