System.InvalidCastException: Conversion from string "holesaws--arbors--hollow-cutters" to type 'Integer' is not valid. ---> System.FormatException: Input string was not in a correct format. at Microsoft.VisualBasic.CompilerServices.Conversions.ParseDouble(String Value, NumberFormatInfo NumberFormat) at Microsoft.VisualBasic.CompilerServices.Conversions.ToInteger(String Value) --- End of inner exception stack trace --- at Microsoft.VisualBasic.CompilerServices.Conversions.ToInteger(String Value) at content.Page_Load(Object sender, EventArgs e)