将DataRow值转换为float

Question

I'm working with DataRow and I want to divide every value in the row with a number(taken from a cell from the same row). I've been searching ways to convert the values into float, like from this thread, but casting gives me "Specified cast is not valid" error.

List<DataTable> tblsol = new List<DataTable>();
DataTable now = tblsol.Last();

while (true)
        {
            DataRow fb = now.Rows[v];
            DataRow fb2 = now.Rows[w];
            float akun = (float)fb[fb.Table.Columns.Count - 1] /
            (float)fb[u];
            if (akun > (float)fb2[fb2.Table.Columns.Count - 1] /
            (float)fb2[u])
            {
                if (w == now.Rows.Count - 1) { v = w; break; }
                else { v++; w++; }
            }
            else 
            {
                if (w == now.Rows.Count - 1) { break; }
                else { w++; }

            }
        }

        DataRow bk = now.Rows[v];

        float angkun = Convert.ToSingle(bk[u]);
        for (int dc = 1; dc < now.Columns.Count;dc++)
        {
            bk[dc] = Convert.ToSingle(bk[dc]) / angkun;
        }

I used 2 methods to convert the value into float (using Convert.toSingle and casting), but both ways gave me error. Is there anything else I can do? Or maybe is there something wrong in my code?
ps tblSol is not empty and all variables are already declared.

Answer 1

try float.Parse, but you need to convert the datarow to dynamic/string type for it to be compatible:

var test = (dynamic)fb[fb.Table.Columns.Count - 1];
float boat = float.Parse(test);

Or something similar using float.Parse

Answer 2

You can try after converting it to String like this,

float akun = float.Parse(fb[fb.Table.Columns.Count - 1].ToString()) /
        float.Parse(fb[u].ToString());

Answer 3

As noted in my comment, try casting the relevant columns to Decimal first. It is one of the explicitly supported DataTypes when accessing data from columns of DataRow instances; the valid types are listed in the MSDN DataColumn Reference page