DataSourceCreator.cs

using System;

using System.Collections;

using System.Collections.Generic;

using System.Reflection;

using System.Reflection.Emit;

using System.Text;

using System.Text.RegularExpressions;

namespace SqlSilverlight

    /// <summary>

    /// Thanks to!

    /// http://blog.bodurov.com/How-to-bind-Silverlight-DataGrid-from-IEnumerable-of-IDictionary

    /// </summary>

    public static class DataSourceCreator

        private static readonly Regex PropertNameRegex =

                new Regex(@"^[A-Za-z]+[A-Za-z0-9_]*$", RegexOptions.Singleline);

        private static readonly Dictionary<string, Type> _typeBySigniture =

                new Dictionary<string, Type>();

        public static IEnumerable ToDataSource(this IEnumerable<Dictionary<string, string>> list)

            IDictionary firstDict = null;

            bool hasData = false;

            foreach (IDictionary currentDict in list)

                hasData = true;

                firstDict = currentDict;

                break;

            if (!hasData)

                return new object[] { };

            if (firstDict == null)

                throw new ArgumentException("IDictionary entry cannot be null");

            string typeSigniture = GetTypeSigniture(firstDict);

            Type objectType = GetTypeByTypeSigniture(typeSigniture);

            if (objectType == null)

                TypeBuilder tb = GetTypeBuilder(typeSigniture);

                ConstructorBuilder constructor =

                            tb.DefineDefaultConstructor(

                                        MethodAttributes.Public |

                                        MethodAttributes.SpecialName |

                                        MethodAttributes.RTSpecialName);

                foreach (DictionaryEntry pair in firstDict)

                    if (PropertNameRegex.IsMatch(Convert.ToString(pair.Key), 0))

                        CreateProperty(tb,

                                        Convert.ToString(pair.Key),

                                        GetValueType(pair.Value));

                    else

                        throw new ArgumentException(

                                    @"Each key of IDictionary must be

                                alphanumeric and start with character.");

                objectType = tb.CreateType();

                _typeBySigniture.Add(typeSigniture, objectType);

            return GenerateEnumerable(objectType, list, firstDict);

        private static Type GetTypeByTypeSigniture(string typeSigniture)

            Type type;

            return _typeBySigniture.TryGetValue(typeSigniture, out type) ? type : null;

        private static Type GetValueType(object value)

            return value == null ? typeof(object) : value.GetType();

        private static string GetTypeSigniture(IDictionary firstDict)

            StringBuilder sb = new StringBuilder();

            foreach (DictionaryEntry pair in firstDict)

                sb.AppendFormat("_{0}_{1}", pair.Key, GetValueType(pair.Value));

            return sb.ToString().GetHashCode().ToString().Replace("-", "Minus");

        private static IEnumerable GenerateEnumerable(

                 Type objectType, IEnumerable<Dictionary<string, string>> list, IDictionary firstDict)

            var listType = typeof(List<>).MakeGenericType(new[] { objectType });

            var listOfCustom = Activator.CreateInstance(listType);

            foreach (var currentDict in list)

                if (currentDict == null)

                    throw new ArgumentException("IDictionary entry cannot be null");

                var row = Activator.CreateInstance(objectType);

                foreach (DictionaryEntry pair in firstDict)

                    if (currentDict.ContainsKey(pair.Key as string))

                        PropertyInfo property =

                            objectType.GetProperty(Convert.ToString(pair.Key));

                        property.SetValue(

                            row,

                            Convert.ChangeType(

                                    currentDict[pair.Key as string],

                                    property.PropertyType,

                                    null),

                            null);

                listType.GetMethod("Add").Invoke(listOfCustom, new[] { row });

            return listOfCustom as IEnumerable;

        private static TypeBuilder GetTypeBuilder(string typeSigniture)

            AssemblyName an = new AssemblyName("TempAssembly" + typeSigniture);

            AssemblyBuilder assemblyBuilder =

                AppDomain.CurrentDomain.DefineDynamicAssembly(

                    an, AssemblyBuilderAccess.Run);

            ModuleBuilder moduleBuilder = assemblyBuilder.DefineDynamicModule("MainModule");

            TypeBuilder tb = moduleBuilder.DefineType("TempType" + typeSigniture

                                , TypeAttributes.Public |

                                TypeAttributes.Class |

                                TypeAttributes.AutoClass |

                                TypeAttributes.AnsiClass |

                                TypeAttributes.BeforeFieldInit |

                                TypeAttributes.AutoLayout

                                , typeof(object));

            return tb;

        private static void CreateProperty(

                        TypeBuilder tb, string propertyName, Type propertyType)

            FieldBuilder fieldBuilder = tb.DefineField("_" + propertyName,

                                                        propertyType,

                                                        FieldAttributes.Private);

            PropertyBuilder propertyBuilder =

                tb.DefineProperty(

                    propertyName, PropertyAttributes.HasDefault, propertyType, null);

            MethodBuilder getPropMthdBldr =

                tb.DefineMethod("get_" + propertyName,

                    MethodAttributes.Public |

                    MethodAttributes.SpecialName |

                    MethodAttributes.HideBySig,

                    propertyType, Type.EmptyTypes);

            ILGenerator getIL = getPropMthdBldr.GetILGenerator();

            getIL.Emit(OpCodes.Ldarg_0);

            getIL.Emit(OpCodes.Ldfld, fieldBuilder);

            getIL.Emit(OpCodes.Ret);

            MethodBuilder setPropMthdBldr =

                tb.DefineMethod("set_" + propertyName,

                  MethodAttributes.Public |

                  MethodAttributes.SpecialName |

                  MethodAttributes.HideBySig,

                  null, new Type[] { propertyType });

            ILGenerator setIL = setPropMthdBldr.GetILGenerator();

            setIL.Emit(OpCodes.Ldarg_0);

            setIL.Emit(OpCodes.Ldarg_1);

            setIL.Emit(OpCodes.Stfld, fieldBuilder);

            setIL.Emit(OpCodes.Ret);

            propertyBuilder.SetGetMethod(getPropMthdBldr);

            propertyBuilder.SetSetMethod(setPropMthdBldr);