TemplateReplacer

using System;
using System.Linq;
using System.Text;

namespace SkillSource.Infrastructure.Web
{
    public static class TemplateReplacer
    {
        /// <summary>
        /// Replaces all [tags] and [tag.tags] found in the template with the corresponding value in the model
        /// </summary>
        /// <param name="template">the template</param>
        /// <param name="model">any model</param>
        /// <returns>the filled in template</returns>
        public static string Replace(string template, object model)
        {
            var result = new StringBuilder();
            for (var pos = 0;pos < template.Length;) {
                var nextOpenBracket = template.IndexOf('[', pos);
                if (nextOpenBracket >= 0) {
                    result.Append(template.Substring(pos, nextOpenBracket - pos));
                    var nextCloseBracket = template.IndexOf(']', nextOpenBracket);
                    if (nextCloseBracket >= 0) {
                        pos = nextCloseBracket + 1;
                        var path = template.Substring(nextOpenBracket + 1, nextCloseBracket - nextOpenBracket - 1);
                        result.Append(ResolvePath(model, path));
                    }
                    else throw new InvalidOperationException("Bracket at pos " + nextOpenBracket + " not closed!");
                }
                else {
                    // till end of template
                    result.Append(template.Substring(pos));
                    break;
                }
            }
            return result.ToString();
        }

        private static string ResolvePath(object model, string paths)
        {
            var parts = paths.Split('.');
            object[] value = {model};

            foreach (var property in parts.Select(part => value[0].GetType().GetProperty(part))) {
                if (property == null) return "[" + paths + "]";
                value[0] = property.GetValue(value[0], null);
            }

            return value[0].ToString();
        }
    }
}