mcs/class/referencesource/System.Web.Entity/System/Data/WebControls/EntityDataSourceWrapper.cs

   1 //---------------------------------------------------------------------
   2 // <copyright file="EntityDataSourceWrapper.cs" company="Microsoft">
   3 //      Copyright (c) Microsoft Corporation.  All rights reserved.
   4 // </copyright>
   5 //
   6 // @owner       [....]
   7 // @backupOwner [....]
   8 //---------------------------------------------------------------------
   9 using System;
  10 using System.Data;
  11 using System.Configuration;
  12 using System.ComponentModel;
  13 using System.Data.Common;
  14 using System.Data.Metadata.Edm;
  15 using System.Reflection;
  16 using System.Data.Objects;
  17 using System.Data.Objects.DataClasses;
  18 using System.Collections.Generic;
  19 using System.Diagnostics;
  20 using System.Linq;
  21 using System.Collections.ObjectModel;
  22 using System.Text;
  23 using System.Web.UI;
  24
  25 namespace System.Web.UI.WebControls
  26 {
  27     /// <summary>
  28     /// Wraps an entity displayed in the data source in an ICustomTypeDescriptor
  29     /// implementation that flattens complex types and exposes references.
  30     /// </summary>
  31     internal class EntityDataSourceWrapper : ICustomTypeDescriptor
  32     {
  33         private readonly EntityDataSourceWrapperCollection _collection;
  34         private readonly ObjectStateEntry _stateEntry;
  35
  36         internal EntityDataSourceWrapper(EntityDataSourceWrapperCollection collection, object trackedEntity)
  37         {
  38             EntityDataSourceUtil.CheckArgumentNull(collection, "collection");
  39             EntityDataSourceUtil.CheckArgumentNull(trackedEntity, "trackedEntity");
  40
  41             this._collection = collection;
  42
  43             // retrieve state entry
  44             if (!this._collection.Context.ObjectStateManager.TryGetObjectStateEntry(trackedEntity, out _stateEntry))
  45             {
  46                 throw new ArgumentException(Strings.ComponentNotFromProperCollection, "trackedEntity");
  47             }
  48         }
  49
  50         /// <summary>
  51         /// Gets entity wrapped by this type descriptor.
  52         /// </summary>
  53         internal object WrappedEntity
  54         {
  55             get
  56             {
  57                 return this._stateEntry.Entity;
  58             }
  59         }
  60
  61         internal RelationshipManager RelationshipManager
  62         {
  63             get
  64             {
  65                 return this._stateEntry.RelationshipManager;
  66             }
  67         }
  68
  69         /// <summary>
  70         /// Gets collection containing this wrapper.
  71         /// </summary>
  72         internal EntityDataSourceWrapperCollection Collection
  73         {
  74             get { return this._collection; }
  75         }
  76
  77         #region ICustomTypeDescriptor Implementation
  78         System.ComponentModel.AttributeCollection System.ComponentModel.ICustomTypeDescriptor.GetAttributes() { return new System.ComponentModel.AttributeCollection(); }
  79         string ICustomTypeDescriptor.GetClassName() { return null; }
  80         string ICustomTypeDescriptor.GetComponentName() { return null; }
  81         TypeConverter ICustomTypeDescriptor.GetConverter() { return null; }
  82         EventDescriptor ICustomTypeDescriptor.GetDefaultEvent() { return null; }
  83         PropertyDescriptor ICustomTypeDescriptor.GetDefaultProperty() { return null; }
  84         object ICustomTypeDescriptor.GetEditor(Type editorBaseType) { return null; }
  85         EventDescriptorCollection ICustomTypeDescriptor.GetEvents() { return null; }
  86         EventDescriptorCollection ICustomTypeDescriptor.GetEvents(Attribute[] attributes) { return null; }
  87
  88
  89         public PropertyDescriptorCollection GetProperties()
  90         {
  91             return ((ITypedList)this._collection).GetItemProperties(null);
  92         }
  93
  94         PropertyDescriptorCollection ICustomTypeDescriptor.GetProperties(Attribute[] attributes)
  95         {
  96             return ((ICustomTypeDescriptor)this).GetProperties();
  97         }
  98
  99         object ICustomTypeDescriptor.GetPropertyOwner(PropertyDescriptor pd)
 100         {
 101             return this.WrappedEntity;
 102         }
 103         #endregion ICustomTypeDescriptor Implementation
 104
 105         /// <summary>
 106         /// Use this method to set the properties on the wrapped entity
 107         /// </summary>
 108         /// <param name="propertiesFromViewState"></param>
 109         /// <param name="wrapper"></param>
 110         /// <param name="overwriteSameValue"></param>
 111         internal void SetAllProperties(Dictionary<string, object> propertiesFromViewState, bool overwriteSameValue,
 112             ref Dictionary<string, Exception> propertySettingExceptionsCaught)
 113         {
 114             // We aggregate the reference descriptors rather than setting them directly
 115             // to account for compound keys (we need all components of the key to create
 116             // an EntityKey that can be set on the EntityReference)
 117             var referenceList = new List<KeyValuePair<EntityDataSourceReferenceKeyColumn, object>>();
 118
 119             foreach (EntityDataSourceWrapperPropertyDescriptor descriptor in _collection.AllPropertyDescriptors)
 120             {
 121                 // figure out which display name to match for this descriptor
 122                 string displayName = descriptor.Column.DisplayName;
 123
 124                 // if we have a controlling column, use its display name instead
 125                 if (descriptor.Column.ControllingColumn != null)
 126                 {
 127                     displayName = descriptor.Column.ControllingColumn.DisplayName;
 128                 }
 129
 130                 object value;
 131                 if (propertiesFromViewState.TryGetValue(displayName, out value))
 132                 {
 133                     // get all changed ReferencePropertyDescriptor from ViewState
 134                     EntityDataSourceReferenceKeyColumn referenceColumn = descriptor.Column as EntityDataSourceReferenceKeyColumn;
 135
 136                     // convert the value as needed
 137                     object adjustedValue = EntityDataSourceUtil.ConvertType(value, descriptor.PropertyType, descriptor.DisplayName);
 138
 139                     if (null != referenceColumn)
 140                     {
 141                         referenceList.Add(new KeyValuePair<EntityDataSourceReferenceKeyColumn, object>(
 142                                 referenceColumn, adjustedValue));
 143                         continue;
 144                     }
 145
 146                     if (overwriteSameValue || adjustedValue != descriptor.GetValue(this))
 147                     {
 148                         if (EntityDataSourceUtil.NullCanBeAssignedTo(descriptor.PropertyType) || null != adjustedValue)
 149                         {
 150                             try
 151                             {
 152                                 descriptor.SetValue(this, adjustedValue);
 153                             }
 154                             catch (Exception e)
 155                             {
 156                                 // The property descriptor uses reflection to set the property. Therefore, the inner exception contains the actual message.
 157                                 Exception exceptionToThrow = e;
 158                                 if (e.InnerException != null)
 159                                 {
 160                                     exceptionToThrow = e.InnerException;
 161                                 }
 162                                 if (null == propertySettingExceptionsCaught)
 163                                 {
 164                                     propertySettingExceptionsCaught = new Dictionary<string, Exception>();
 165                                 }
 166                                 propertySettingExceptionsCaught.Add(descriptor.DisplayName, exceptionToThrow);
 167                             }
 168                         }
 169                     }
 170                 }
 171             }
 172
 173             // aggregate setting for EntityKey
 174             SetEntityKeyProperties(referenceList, overwriteSameValue);
 175         }
 176
 177         private void SetEntityKeyProperties(
 178             List<KeyValuePair<EntityDataSourceReferenceKeyColumn, object>> referenceList, bool overwriteSameValue)
 179         {
 180             EntityDataSourceUtil.CheckArgumentNull(referenceList, "referenceList");
 181
 182             var groups = referenceList.GroupBy(r => r.Key.Group);
 183
 184             foreach (var group in groups)
 185             {
 186                 Dictionary<string, object> partialKeys = new Dictionary<string, object>();
 187
 188                 foreach (KeyValuePair<EntityDataSourceReferenceKeyColumn, object> reference in group)
 189                 {
 190                     // convert the value as needed
 191                     EntityDataSourceReferenceKeyColumn column = reference.Key;
 192                     object keyValue = reference.Value;
 193
 194                     if (null == keyValue)
 195                     {
 196                         partialKeys = null;
 197                         break;
 198                     }
 199
 200                     partialKeys.Add(column.KeyMember.Name, keyValue);
 201                 }
 202
 203                 // we only set the entitykey for once, although there might be more than one
 204                 // properties descriptor associated with the same entitykey
 205                 group.Key.SetKeyValues(this, partialKeys);
 206             }
 207         }
 208     }
 209 }