asp.net grid view extensions

asp.net grid view extensions.aspx.cs

using System;
using System.Collections.Generic;
using System.Globalization;
using System.Web.UI.WebControls;

namespace ClientPortal
{
    public static class Extensions
    {
        /// <extends><c>GridView</c></extends>
        /// <summary>
        /// </summary>
        /// <param name="row"></param>
        /// <param name="field"></param>
        /// <returns>The <c>TableCell</c> of the column bound to the field named <paramref name="field"/></returns>
        public static TableCell GetCell(this GridViewRow row, string field)
        {
            var gv = (GridView)row.NamingContainer;
            for (int columnIndex = 0; columnIndex < gv.Columns.Count; columnIndex++)
            {
                var boundField = gv.Columns[columnIndex] as BoundField;
                if (boundField != null && boundField.DataField == field)
                {
                    return row.Cells[columnIndex];
                }
                var templateField = gv.Columns[columnIndex] as TemplateField;
                if (templateField != null && templateField.HeaderText == field)
                {
                    return row.Cells[columnIndex];
                }
            }
            throw new Exception("Could not find index of  " + field);
        }

        /// <summary>
        /// </summary>
        /// <param name="row"></param>
        /// <param name="field"></param>
        /// <returns></returns>
        public static string GetCellText(this GridViewRow row, string field)
        {
            TableCell cell = row.GetCell(field);
            if (cell.Controls.Count > 0)
            {
                if (cell.Controls[1] is Label)
                {
                    return (cell.Controls[1] as Label).Text;
                }
            }
            return cell.Text;
        }

        /// <summary>
        /// </summary>
        /// <param name="row"></param>
        /// <param name="field"></param>
        /// <param name="text"></param>
        /// <returns></returns>
        public static void SetCellText(this GridViewRow row, string field, string text)
        {
            try
            {
                row.GetCell(field).Text = text;
            }
            catch
            {
                // setting the text of a non existant row has no effect
            }
        }

        /// <summary>
        /// </summary>
        /// <param name="row"></param>
        /// <param name="field"></param>
        /// <param name="func"></param>
        public static void ChangeCellText(this GridViewRow row, string field, Func<string, string> func)
        {
            string toText = func(row.GetCell(field).Text);
            if(string.IsNullOrWhiteSpace(toText))
            {
                toText = _EmptyCellText;
            }
            row.SetCellText(field, toText);
        }

        /// <extends>decimal</extends>
        /// <summary>
        /// </summary>
        /// <param name="amount"></param>
        /// <param name="currency"></param>
        /// <returns>A string representation of the decimal <paramref name="amount"/> 
        /// formatted as the <paramref name="currency"/>.</returns>
        public static string ToCurrency(this decimal amount, string currency)
        {
            if (!_CurrencyMap.ContainsKey(currency))
            {
                throw new Exception("Unsupported target currency: " + currency);
            }

            if (amount == 0)
            {
                return _EmptyCellText;
            }
            else
            {
                CultureInfo culture = CultureInfo.CreateSpecificCulture(_CurrencyMap[currency]);
                return string.Format(culture, "{0:C}", amount);
            }
        }

        /// <summary>
        /// Trims off trailing zeros and decimal points.
        /// </summary>
        /// <param name="number"></param>
        /// <returns></returns>
        public static string ToNumber(this string number)
        {
           return number.TrimEnd('.', '0');
        }

        static string _EmptyCellText = "-";

        static Dictionary<string, string> _CurrencyMap = new Dictionary<string, string>
        {
            {"USD", "en-us"},
            {"GBP", "en-gb"},
            {"EUR", "de-de"},
            {"AUD", "en-AU"},
            {"CAD", "en-us"},
            // add additional currencies here
        };
    }
}