Entity Framework 实体不在 DataSpace.OSpace (_workspace.GetItemCollection(DataSpace.OSpace)) 但在 DataSpace.CSpace
Entity Framework entity is not in DataSpace.OSpace (_workspace.GetItemCollection(DataSpace.OSpace)) but is in DataSpace.CSpace
我一直在为 entity Framework 摆弄 XMLs。我试图创建一种可以在运行时注入属性的实体，
首先，我创建了 DynamicEntity 动态对象
public class DynamicEntity : DynamicObject
{
Dictionary<string, object> dynamicMembers = new Dictionary<string, object>();
public override bool TrySetMember(SetMemberBinder binder, object value)
{
dynamicMembers[binder.Name] = value;
return true;
}
public override bool TryGetMember(GetMemberBinder binder, out object result)
{
if (dynamicMembers.TryGetValue(binder.Name, out result))
{
return dynamicMembers.TryGetValue(binder.Name, out result);
}
result = "";
return true;
}
}
然后实体继承自这个
public partial class QUOTE_HOUSE : DynamicEntity
（当我从数据库获取数据后手动设置属性时，它似乎确实有效）。
我试着做另一个将属性插入 XML 的方法，整个事情似乎都没有问题（至少它不会在映射上爆炸，而当 XML 不正确时它通常会这样做 var mappingCollection = new StorageMappingItemCollection(conceptualCollection, storageCollection, new[] {mappingXml.CreateReader()});).
执行查询时 EF 出现问题
The entity type QUOTE_HOUSE is not part of the model for the current context.
Description: An unhandled exception occurred during the execution of
the current web request. Please review the stack trace for more
information about the error and where it originated in the code.
Exception Details: System.InvalidOperationException: The entity type
QUOTE_HOUSE is not part of the model for the current context.
[InvalidOperationException: The entity type QUOTE_HOUSE is not part of
the model for the current context.]
System.Data.Entity.Internal.InternalContext.UpdateEntitySetMappingsForType(Type
entityType) +208
System.Data.Entity.Internal.InternalContext.GetEntitySetAndBaseTypeForType(Type
entityType) +50
在为 EF
加载 pdb 后，我在 System.Data.Entity.Internal.InternalContext 中追踪到 TryUpdateEntitySetMappingsForType
基本上我的 QUOTE_HOUSE 不在 this._workspace.GetItemCollection(DataSpace.OSpace) 中 UpdateEntitySetMappings 试图从中映射它。
它检查它是否在 this._entitySetMappingsCache.ContainsKey(entityType)) 中，因为它不在，然后尝试更新映射迭代 this._workspace.GetItemCollection(DataSpace.OSpace) 我的项目不存在
但是我可以看到我的实体确实存在于 this._workspace.GetItems<EntityContainer>(DataSpace.CSpace)。
完整 UpdateEntitySetMappings 如下所示：
private void UpdateEntitySetMappings()
{
ObjectItemCollection objectItemCollection = (ObjectItemCollection) this._workspace.GetItemCollection(DataSpace.OSpace);
ReadOnlyCollection<EntityType> items = this._workspace.GetItems<EntityType>(DataSpace.OSpace);
Stack<EntityType> entityTypeStack = new Stack<EntityType>();
foreach (EntityType entityType1 in items)
{
entityTypeStack.Clear();
EntityType cspaceType = (EntityType) this._workspace.GetEdmSpaceType((StructuralType) entityType1);
do
{
entityTypeStack.Push(cspaceType);
cspaceType = (EntityType) cspaceType.BaseType;
}
while (cspaceType != null);
EntitySet entitySet = (EntitySet) null;
while (entitySet == null && entityTypeStack.Count > 0)
{
cspaceType = entityTypeStack.Pop();
foreach (EntityContainer entityContainer in this._workspace.GetItems<EntityContainer>(DataSpace.CSpace))
{
List<EntitySetBase> list = entityContainer.BaseEntitySets.Where<EntitySetBase>((Func<EntitySetBase, bool>) (s => s.ElementType == cspaceType)).ToList<EntitySetBase>();
int count = list.Count;
if (count > 1 || count == 1 && entitySet != null)
throw Error.DbContext_MESTNotSupported();
if (count == 1)
entitySet = (EntitySet) list[0];
}
}
if (entitySet != null)
{
EntityType entityType2 = (EntityType) this._workspace.GetObjectSpaceType((StructuralType) cspaceType);
Type clrType1 = objectItemCollection.GetClrType((StructuralType) entityType1);
Type clrType2 = objectItemCollection.GetClrType((StructuralType) entityType2);
this._entitySetMappingsCache[clrType1] = new EntitySetTypePair(entitySet, clrType2);
}
}
}
实体如何进入this._workspace.GetItemCollection(DataSpace.OSpace)？
为什么实体会在 CSpace 而不是在 OSpace 中？
编辑：
对于那些可能想要获得赏金的人，以下是您可能需要设置环境以重现问题的组件。
public class SystemToDatabaseMapping
{
public SystemToDatabaseMapping(string system, string databaseType, string database, string connectionString, Type enitityType)
{
System = system;
Database = database;
DatabaseType = databaseType;
ConnectionString = connectionString;
EntityType = enitityType;
}
public Type EntityType { get; set; }
public string System { get; set; }
public string Database { get; set; }
public string DatabaseType { get; set; }
public string ConnectionString { get; set; }
public List<ColumnToModify> ColumnsToModify { get; set; }
}
public abstract class ColumnToModify
{
protected ColumnToModify(string table, string column)
{
Table = table;
Column = column;
}
public string Table { get; set; }
public string Column { get; set; }
public abstract bool IsRemove{ get; }
}
public class ColumnToRemove : ColumnToModify
{
public ColumnToRemove(string table, string column) : base(table, column)
{
}
public override bool IsRemove
{
get { return true; }
}
}
public class ColumnToAdd : ColumnToModify
{
public ColumnToAdd(string table, string column, Type type) : base(table, column)
{
this.Type = type;
}
public override bool IsRemove
{
get { return false; }
}
public Type Type { get; set; }
}
首先从数据库生成实体，（DynamicEntity代码在上面）
public partial class QUOTE_HOUSE : DynamicEntity
{
public long UNIQUE_ID { get; set; }
}
数据库的 DbContext 需要构造函数重载
public partial class EcomEntities : DbContext
{
public EcomEntities(DbConnection connectionString)
: base(connectionString, false)
{
}
public virtual DbSet<QUOTE_HOUSE > QUOTE_HOUSE { get; set; }
....
}
进行列注入的机制（这是一个粗略的原型，所以请原谅它看起来有多糟糕），当注入尝试字符串列时，我知道它映射正常。
public static class EntityConnectionExtensions
{
public static IEnumerable<XElement> ElementsAnyNS<T>(this IEnumerable<T> source, string localName)
where T : XContainer
{
return source.Elements().Where(e => e.Name.LocalName == localName);
}
public static IEnumerable<XElement> ElementsAnyNS(this XContainer source, string localName)
{
return source.Elements().Where(e => e.Name.LocalName == localName);
}
private static void ModifyNodes(XElement element, List<ColumnToModify> tableAndColumn)
{
if (element.Attribute("Name") != null && tableAndColumn.Any(oo => oo.Table == element.Attribute("Name").Value) ||
element.Attribute("StoreEntitySet") != null && tableAndColumn.Any(oo => oo.Table == element.Attribute("StoreEntitySet").Value))
{
var matchingRemoveSelectParts = tableAndColumn.Where(oo => oo.IsRemove && element.Value.Contains(string.Format("\"{0}\".\"{1}\" AS \"{1}\"", oo.Table, oo.Column))).ToList();
if (matchingRemoveSelectParts.Any())
{
foreach (var matchingRemoveSelectPart in matchingRemoveSelectParts)
{
var definingQuery = element.ElementsAnyNS("DefiningQuery").Single();
definingQuery.Value = definingQuery.Value.Replace(string.Format(", \n\"{0}\".\"{1}\" AS \"{1}\"", matchingRemoveSelectPart.Table, matchingRemoveSelectPart.Column), "");
}
}
else
{
var nodesToRemove = element.Nodes()
.Where(o =>
o is XElement
&& ((XElement) o).Attribute("Name") != null
&& tableAndColumn.Any(oo => oo.IsRemove && ((XElement) o).Attribute("Name").Value == oo.Column));
foreach (var node in nodesToRemove.ToList())
{
node.Remove();
}
if (element.Attribute("Name") != null && tableAndColumn.Any(oo => oo.Table == element.Attribute("Name").Value))
{
var elementsToAdd = tableAndColumn.Where(o => !o.IsRemove && o.Table == element.Attribute("Name").Value);
if (new[] {"Type=\"number\"", "Type=\"varchar2\"", "Type=\"date\""}.Any(o => element.ToString().Contains(o)))
{
foreach (var columnToModify in elementsToAdd)
{
var columnToAdd = (ColumnToAdd) columnToModify;
var type = new[] {typeof (decimal), typeof (float), typeof (int), typeof (bool)}.Contains(columnToAdd.Type)
? "number"
: columnToAdd.Type == typeof (DateTime) ? "date" : "varchar2";
var precision = "";
var scale = "";
var maxLength = "";
if (type == "number")
{
precision = "38";
scale = new[] {typeof (decimal), typeof (float)}.Contains(columnToAdd.Type) ? "2" : "0";
}
if (type == "varchar2")
{
maxLength = "500";
}
var newProperty = new XElement(element.GetDefaultNamespace() + "Property", new XAttribute("Name", columnToAdd.Column), new XAttribute("Type", type));
if (!string.IsNullOrWhiteSpace(precision))
{
newProperty.Add(new XAttribute("Precision", precision));
}
if (!string.IsNullOrWhiteSpace(scale))
{
newProperty.Add(new XAttribute("Scale", scale));
}
if (!string.IsNullOrWhiteSpace(maxLength))
{
newProperty.Add(new XAttribute("MaxLength", maxLength));
}
element.Add(newProperty);
}
}
else if (
new[] {"Type=\"Decimal\"", "Type=\"String\"", "Type=\"DateTime\"", "Type=\"Boolean\"", "Type=\"Byte\"", "Type=\"Int16\"", "Type=\"Int32\"", "Type=\"Int64\""}.Any(
o => element.ToString().Contains(o)))
{
foreach (var columnToModify in elementsToAdd)
{
var columnToAdd = (ColumnToAdd) columnToModify;
var type = new[] {typeof (decimal), typeof (float), typeof (int), typeof (bool)}.Contains(columnToAdd.Type)
? "Decimal"
: columnToAdd.Type == typeof (DateTime) ? "DateTime" : "String";
var precision = "";
var scale = "";
var maxLength = "";
if (type == "Decimal")
{
precision = "38";
scale = new[] {typeof (decimal), typeof (float)}.Contains(columnToAdd.Type) ? "2" : "0";
}
if (type == "String")
{
maxLength = "500";
}
var newProperty = new XElement(element.GetDefaultNamespace() + "Property", new XAttribute("Name", columnToAdd.Column), new XAttribute("Type", type));
if (!string.IsNullOrWhiteSpace(precision))
{
newProperty.Add(new XAttribute("Precision", precision));
}
if (!string.IsNullOrWhiteSpace(scale))
{
newProperty.Add(new XAttribute("Scale", scale));
}
if (!string.IsNullOrWhiteSpace(maxLength))
{
newProperty.Add(new XAttribute("MaxLength", maxLength));
newProperty.Add(new XAttribute("FixedLength", "false"));
newProperty.Add(new XAttribute("Unicode", "false"));
}
element.Add(newProperty);
}
}
}
}
if (element.Attribute("Name") != null && tableAndColumn.Any(oo => oo.Table == element.Attribute("Name").Value) && element.GetNamespaceOfPrefix("store") != null &&
element.Attribute(element.GetNamespaceOfPrefix("store") + "Type") != null &&
element.Attribute(element.GetNamespaceOfPrefix("store") + "Type").Value == "Tables")
{
var matchingAddSelectParts = tableAndColumn.Where(o => !o.IsRemove && o.Table == element.Attribute("Name").Value);
foreach (var matchingAddSelectPart in matchingAddSelectParts)
{
var definingQuery = element.ElementsAnyNS("DefiningQuery").Single();
var schemaRegex = new Regex(string.Format("\nFROM \\"([a-zA-Z0-9]*)\\".\\"{0}\\"", matchingAddSelectPart.Table));
var schema = schemaRegex.Matches(definingQuery.Value)[0].Groups[1].Value;
definingQuery.Value = definingQuery.Value.Replace(
string.Format("\nFROM \"{0}\".\"{1}\" \"{1}\"", schema, matchingAddSelectPart.Table),
string.Format(", \n\"{0}\".\"{1}\" AS \"{1}\"\nFROM \"{2}\".\"{0}\" \"{0}\"", matchingAddSelectPart.Table, matchingAddSelectPart.Column, schema));
}
}
if (element.Attribute("StoreEntitySet") != null && tableAndColumn.Any(oo => !oo.IsRemove && oo.Table == element.Attribute("StoreEntitySet").Value))
{
var matchingAddSelectParts = tableAndColumn.Where(o => !o.IsRemove && o.Table == element.Attribute("StoreEntitySet").Value);
foreach (var matchingAddSelectPart in matchingAddSelectParts)
{
element.Add(new XElement(element.GetDefaultNamespace() + "ScalarProperty", new XAttribute("Name", matchingAddSelectPart.Column),
new XAttribute("ColumnName", matchingAddSelectPart.Column)));
}
}
}
}
public static EntityConnection Create(List<ColumnToModify> tablesAndColumns, string connString)
{
var modelNameRegex = new Regex(@".*metadata=res:\/\/\*\/([a-zA-Z.]*).csdl|.*");
var model = modelNameRegex.Matches(connString).Cast<Match>().SelectMany(o => o.Groups.Cast<Group>().Skip(1).Where(oo => oo.Value != "")).Select(o => o.Value).First();
var conceptualReader = XmlReader.Create(Assembly.GetExecutingAssembly().GetManifestResourceStream(model + ".csdl"));
var mappingReader = XmlReader.Create(Assembly.GetExecutingAssembly().GetManifestResourceStream(model + ".msl"));
var storageReader = XmlReader.Create(Assembly.GetExecutingAssembly().GetManifestResourceStream(model + ".ssdl"));
var conceptualXml = XElement.Load(conceptualReader);
var mappingXml = XElement.Load(mappingReader);
var storageXml = XElement.Load(storageReader);
foreach (var entitySet in new[] {storageXml, conceptualXml}.SelectMany(xml => xml.Elements()))
{
if (entitySet.Attribute("Name").Value == "ModelStoreContainer")
{
foreach (var entityContainerEntitySet in entitySet.Elements())
{
ModifyNodes(entityContainerEntitySet, tablesAndColumns);
}
}
ModifyNodes(entitySet, tablesAndColumns);
}
foreach (var entitySet in mappingXml.Elements().ElementAt(0).Elements())
{
if (entitySet.Name.LocalName == "EntitySetMapping")
{
foreach (var entityContainerEntitySet in entitySet.Elements().First().Elements())
{
ModifyNodes(entityContainerEntitySet, tablesAndColumns);
}
}
ModifyNodes(entitySet, tablesAndColumns);
}
var storageCollection = new StoreItemCollection(new [] {storageXml.CreateReader()});
var conceptualCollection = new EdmItemCollection(new[] { conceptualXml.CreateReader() });
var mappingCollection = new StorageMappingItemCollection(conceptualCollection, storageCollection, new[] {mappingXml.CreateReader()});
var workspace = new MetadataWorkspace();
workspace.RegisterItemCollection(conceptualCollection);
workspace.RegisterItemCollection(storageCollection);
workspace.RegisterItemCollection(mappingCollection);
var connectionData = new EntityConnectionStringBuilder(connString);
var connection = DbProviderFactories
.GetFactory(connectionData.Provider)
.CreateConnection();
connection.ConnectionString = connectionData.ProviderConnectionString;
return new EntityConnection(workspace, connection);
}
}
初始化：
public ActionResult QUOTE_HOUSE()
{
var onlineDocs = Enumerable.Empty<QUOTE_HOUSE>();
var mappings = new List<SagaSystemToDatabaseMapping>{new SagaSystemToDatabaseMapping("x", "Oracle", "Db1",
"metadata=res://*/Ecom.Ecom.csdl|res://*/Ecom.Ecom.ssdl|res://*/Ecom.Ecom.msl;provider=Oracle.ManagedDataAccess.Client;provider connection string='...'", typeof(EcomEntities))
{
ColumnsToModify = new List<ColumnToModify> { new ColumnToAdd("QUOTE_HOUSE","TESTCOL", typeof(string)) }
}};
var entityConnection = EntityConnectionExtensions.Create(mappings[0].ColumnsToModify,mappings[0].ConnectionString);
using (var db = new EcomEntities(entityConnection))
{
onlineDocs = db.QUOTE_HOUSE.Take(10);
}
return View("QUOTE_HOUSE", onlineDocs.ToList());
}
您应该能够从实体 QUOTE_HOUSE 生成 oracle 数据库并输入一些虚拟值，不要认为您需要一个视图，因为它在 .ToList() 上爆炸了。生成数据库后，向数据库添加其他列但不向模型添加列 (alter table QUOTE_HOUSE
add TESTCOL Varchar2(20)) - 使数据库中的列在运行时注入模型。您可能还需要调试 EF assemblies here's how to do it。如果您需要更多信息或者我遗漏了什么，请告诉我。
我知道这可能不是您所期望的，但我想至少它会帮助您避免在那个方向上浪费更多时间。
好消息是问题不是由您的 "hackish" 代码引起的。事实上，我能够在不使用该代码的情况下重现该问题。刚刚创建了一个包含 TestCol 的 QUOTE_HOUSE table，将其导入到新的 edmx 上下文中，并刚刚从实体 [=50= 中删除了生成的 TestCol 属性 ].然后我让 class 继承了 DynamicEntity，使用默认构造函数创建了一个名为 context.QUOTE_HOUSE.ToList() 的上下文，它因完全相同的异常而爆炸。
坏消息是你想要达到的目标是不可能的。 EF 仅使用反射来映射 "object space" 成员。它不提供任何类型扩展机制，例如 TypeDescriptor 或动态 运行time（它甚至不允许您投影到动态对象）。后者是可以理解的，因为每个动态对象可能具有不同的属性，并且没有动态type这样的东西。请注意，在 运行 时使用 "removing" 列的技巧是有效的，因为它所做的与首先在代码中使用 NotMapped 基本相同，即 属性 确实存在，但是被 EF 忽略。
如果您对为什么实体在 CSpace 但不在 OSpace 中感兴趣，答案包含在名为 OSpaceTypeFactory 的内部 class 中（在 System.Data.Entity.Core.Metadata.Edm 命名空间）- source。有一个方法叫做TryCreateStructuralType，它调用TryCreateMembers如果是returnsfalse，则不添加类型。 TryCreateMembers 轮流调用 TryFindAndCreatePrimitiveProperties，传递使用反射提取的 PropertyInfo 列表，如果不能映射 any[，则传递后面的 returns false =44=] CSpace 成员到 OSpace 对象 属性，从而有效地防止将类型添加到 OSpace 类型集合中。
希望至少能满足您的好奇心 :) 但是，不幸的是，"adding" 属性在 运行 时间到 EF 实体是一个死主意。
我一直在为 entity Framework 摆弄 XMLs。我试图创建一种可以在运行时注入属性的实体，
首先，我创建了 DynamicEntity 动态对象
public class DynamicEntity : DynamicObject
{
Dictionary<string, object> dynamicMembers = new Dictionary<string, object>();
public override bool TrySetMember(SetMemberBinder binder, object value)
{
dynamicMembers[binder.Name] = value;
return true;
}
public override bool TryGetMember(GetMemberBinder binder, out object result)
{
if (dynamicMembers.TryGetValue(binder.Name, out result))
{
return dynamicMembers.TryGetValue(binder.Name, out result);
}
result = "";
return true;
}
}
然后实体继承自这个
public partial class QUOTE_HOUSE : DynamicEntity
（当我从数据库获取数据后手动设置属性时，它似乎确实有效）。
var mappingCollection = new StorageMappingItemCollection(conceptualCollection, storageCollection, new[] {mappingXml.CreateReader()});).
执行查询时 EF 出现问题
The entity type QUOTE_HOUSE is not part of the model for the current context.
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.InvalidOperationException: The entity type QUOTE_HOUSE is not part of the model for the current context.
[InvalidOperationException: The entity type QUOTE_HOUSE is not part of the model for the current context.]
System.Data.Entity.Internal.InternalContext.UpdateEntitySetMappingsForType(Type entityType) +208
System.Data.Entity.Internal.InternalContext.GetEntitySetAndBaseTypeForType(Type entityType) +50
在为 EF
System.Data.Entity.Internal.InternalContext 中追踪到 TryUpdateEntitySetMappingsForType
基本上我的 QUOTE_HOUSE 不在 this._workspace.GetItemCollection(DataSpace.OSpace) 中 UpdateEntitySetMappings 试图从中映射它。
它检查它是否在 this._entitySetMappingsCache.ContainsKey(entityType)) 中，因为它不在，然后尝试更新映射迭代 this._workspace.GetItemCollection(DataSpace.OSpace) 我的项目不存在
但是我可以看到我的实体确实存在于 this._workspace.GetItems<EntityContainer>(DataSpace.CSpace)。
完整 UpdateEntitySetMappings 如下所示：
private void UpdateEntitySetMappings()
{
ObjectItemCollection objectItemCollection = (ObjectItemCollection) this._workspace.GetItemCollection(DataSpace.OSpace);
ReadOnlyCollection<EntityType> items = this._workspace.GetItems<EntityType>(DataSpace.OSpace);
Stack<EntityType> entityTypeStack = new Stack<EntityType>();
foreach (EntityType entityType1 in items)
{
entityTypeStack.Clear();
EntityType cspaceType = (EntityType) this._workspace.GetEdmSpaceType((StructuralType) entityType1);
do
{
entityTypeStack.Push(cspaceType);
cspaceType = (EntityType) cspaceType.BaseType;
}
while (cspaceType != null);
EntitySet entitySet = (EntitySet) null;
while (entitySet == null && entityTypeStack.Count > 0)
{
cspaceType = entityTypeStack.Pop();
foreach (EntityContainer entityContainer in this._workspace.GetItems<EntityContainer>(DataSpace.CSpace))
{
List<EntitySetBase> list = entityContainer.BaseEntitySets.Where<EntitySetBase>((Func<EntitySetBase, bool>) (s => s.ElementType == cspaceType)).ToList<EntitySetBase>();
int count = list.Count;
if (count > 1 || count == 1 && entitySet != null)
throw Error.DbContext_MESTNotSupported();
if (count == 1)
entitySet = (EntitySet) list[0];
}
}
if (entitySet != null)
{
EntityType entityType2 = (EntityType) this._workspace.GetObjectSpaceType((StructuralType) cspaceType);
Type clrType1 = objectItemCollection.GetClrType((StructuralType) entityType1);
Type clrType2 = objectItemCollection.GetClrType((StructuralType) entityType2);
this._entitySetMappingsCache[clrType1] = new EntitySetTypePair(entitySet, clrType2);
}
}
}
实体如何进入this._workspace.GetItemCollection(DataSpace.OSpace)？
为什么实体会在 CSpace 而不是在 OSpace 中？
编辑： 对于那些可能想要获得赏金的人，以下是您可能需要设置环境以重现问题的组件。
public class SystemToDatabaseMapping
{
public SystemToDatabaseMapping(string system, string databaseType, string database, string connectionString, Type enitityType)
{
System = system;
Database = database;
DatabaseType = databaseType;
ConnectionString = connectionString;
EntityType = enitityType;
}
public Type EntityType { get; set; }
public string System { get; set; }
public string Database { get; set; }
public string DatabaseType { get; set; }
public string ConnectionString { get; set; }
public List<ColumnToModify> ColumnsToModify { get; set; }
}
public abstract class ColumnToModify
{
protected ColumnToModify(string table, string column)
{
Table = table;
Column = column;
}
public string Table { get; set; }
public string Column { get; set; }
public abstract bool IsRemove{ get; }
}
public class ColumnToRemove : ColumnToModify
{
public ColumnToRemove(string table, string column) : base(table, column)
{
}
public override bool IsRemove
{
get { return true; }
}
}
public class ColumnToAdd : ColumnToModify
{
public ColumnToAdd(string table, string column, Type type) : base(table, column)
{
this.Type = type;
}
public override bool IsRemove
{
get { return false; }
}
public Type Type { get; set; }
}
首先从数据库生成实体，（DynamicEntity代码在上面）
public partial class QUOTE_HOUSE : DynamicEntity
{
public long UNIQUE_ID { get; set; }
}
数据库的 DbContext 需要构造函数重载
public partial class EcomEntities : DbContext
{
public EcomEntities(DbConnection connectionString)
: base(connectionString, false)
{
}
public virtual DbSet<QUOTE_HOUSE > QUOTE_HOUSE { get; set; }
....
}
进行列注入的机制（这是一个粗略的原型，所以请原谅它看起来有多糟糕），当注入尝试字符串列时，我知道它映射正常。
public static class EntityConnectionExtensions
{
public static IEnumerable<XElement> ElementsAnyNS<T>(this IEnumerable<T> source, string localName)
where T : XContainer
{
return source.Elements().Where(e => e.Name.LocalName == localName);
}
public static IEnumerable<XElement> ElementsAnyNS(this XContainer source, string localName)
{
return source.Elements().Where(e => e.Name.LocalName == localName);
}
private static void ModifyNodes(XElement element, List<ColumnToModify> tableAndColumn)
{
if (element.Attribute("Name") != null && tableAndColumn.Any(oo => oo.Table == element.Attribute("Name").Value) ||
element.Attribute("StoreEntitySet") != null && tableAndColumn.Any(oo => oo.Table == element.Attribute("StoreEntitySet").Value))
{
var matchingRemoveSelectParts = tableAndColumn.Where(oo => oo.IsRemove && element.Value.Contains(string.Format("\"{0}\".\"{1}\" AS \"{1}\"", oo.Table, oo.Column))).ToList();
if (matchingRemoveSelectParts.Any())
{
foreach (var matchingRemoveSelectPart in matchingRemoveSelectParts)
{
var definingQuery = element.ElementsAnyNS("DefiningQuery").Single();
definingQuery.Value = definingQuery.Value.Replace(string.Format(", \n\"{0}\".\"{1}\" AS \"{1}\"", matchingRemoveSelectPart.Table, matchingRemoveSelectPart.Column), "");
}
}
else
{
var nodesToRemove = element.Nodes()
.Where(o =>
o is XElement
&& ((XElement) o).Attribute("Name") != null
&& tableAndColumn.Any(oo => oo.IsRemove && ((XElement) o).Attribute("Name").Value == oo.Column));
foreach (var node in nodesToRemove.ToList())
{
node.Remove();
}
if (element.Attribute("Name") != null && tableAndColumn.Any(oo => oo.Table == element.Attribute("Name").Value))
{
var elementsToAdd = tableAndColumn.Where(o => !o.IsRemove && o.Table == element.Attribute("Name").Value);
if (new[] {"Type=\"number\"", "Type=\"varchar2\"", "Type=\"date\""}.Any(o => element.ToString().Contains(o)))
{
foreach (var columnToModify in elementsToAdd)
{
var columnToAdd = (ColumnToAdd) columnToModify;
var type = new[] {typeof (decimal), typeof (float), typeof (int), typeof (bool)}.Contains(columnToAdd.Type)
? "number"
: columnToAdd.Type == typeof (DateTime) ? "date" : "varchar2";
var precision = "";
var scale = "";
var maxLength = "";
if (type == "number")
{
precision = "38";
scale = new[] {typeof (decimal), typeof (float)}.Contains(columnToAdd.Type) ? "2" : "0";
}
if (type == "varchar2")
{
maxLength = "500";
}
var newProperty = new XElement(element.GetDefaultNamespace() + "Property", new XAttribute("Name", columnToAdd.Column), new XAttribute("Type", type));
if (!string.IsNullOrWhiteSpace(precision))
{
newProperty.Add(new XAttribute("Precision", precision));
}
if (!string.IsNullOrWhiteSpace(scale))
{
newProperty.Add(new XAttribute("Scale", scale));
}
if (!string.IsNullOrWhiteSpace(maxLength))
{
newProperty.Add(new XAttribute("MaxLength", maxLength));
}
element.Add(newProperty);
}
}
else if (
new[] {"Type=\"Decimal\"", "Type=\"String\"", "Type=\"DateTime\"", "Type=\"Boolean\"", "Type=\"Byte\"", "Type=\"Int16\"", "Type=\"Int32\"", "Type=\"Int64\""}.Any(
o => element.ToString().Contains(o)))
{
foreach (var columnToModify in elementsToAdd)
{
var columnToAdd = (ColumnToAdd) columnToModify;
var type = new[] {typeof (decimal), typeof (float), typeof (int), typeof (bool)}.Contains(columnToAdd.Type)
? "Decimal"
: columnToAdd.Type == typeof (DateTime) ? "DateTime" : "String";
var precision = "";
var scale = "";
var maxLength = "";
if (type == "Decimal")
{
precision = "38";
scale = new[] {typeof (decimal), typeof (float)}.Contains(columnToAdd.Type) ? "2" : "0";
}
if (type == "String")
{
maxLength = "500";
}
var newProperty = new XElement(element.GetDefaultNamespace() + "Property", new XAttribute("Name", columnToAdd.Column), new XAttribute("Type", type));
if (!string.IsNullOrWhiteSpace(precision))
{
newProperty.Add(new XAttribute("Precision", precision));
}
if (!string.IsNullOrWhiteSpace(scale))
{
newProperty.Add(new XAttribute("Scale", scale));
}
if (!string.IsNullOrWhiteSpace(maxLength))
{
newProperty.Add(new XAttribute("MaxLength", maxLength));
newProperty.Add(new XAttribute("FixedLength", "false"));
newProperty.Add(new XAttribute("Unicode", "false"));
}
element.Add(newProperty);
}
}
}
}
if (element.Attribute("Name") != null && tableAndColumn.Any(oo => oo.Table == element.Attribute("Name").Value) && element.GetNamespaceOfPrefix("store") != null &&
element.Attribute(element.GetNamespaceOfPrefix("store") + "Type") != null &&
element.Attribute(element.GetNamespaceOfPrefix("store") + "Type").Value == "Tables")
{
var matchingAddSelectParts = tableAndColumn.Where(o => !o.IsRemove && o.Table == element.Attribute("Name").Value);
foreach (var matchingAddSelectPart in matchingAddSelectParts)
{
var definingQuery = element.ElementsAnyNS("DefiningQuery").Single();
var schemaRegex = new Regex(string.Format("\nFROM \\"([a-zA-Z0-9]*)\\".\\"{0}\\"", matchingAddSelectPart.Table));
var schema = schemaRegex.Matches(definingQuery.Value)[0].Groups[1].Value;
definingQuery.Value = definingQuery.Value.Replace(
string.Format("\nFROM \"{0}\".\"{1}\" \"{1}\"", schema, matchingAddSelectPart.Table),
string.Format(", \n\"{0}\".\"{1}\" AS \"{1}\"\nFROM \"{2}\".\"{0}\" \"{0}\"", matchingAddSelectPart.Table, matchingAddSelectPart.Column, schema));
}
}
if (element.Attribute("StoreEntitySet") != null && tableAndColumn.Any(oo => !oo.IsRemove && oo.Table == element.Attribute("StoreEntitySet").Value))
{
var matchingAddSelectParts = tableAndColumn.Where(o => !o.IsRemove && o.Table == element.Attribute("StoreEntitySet").Value);
foreach (var matchingAddSelectPart in matchingAddSelectParts)
{
element.Add(new XElement(element.GetDefaultNamespace() + "ScalarProperty", new XAttribute("Name", matchingAddSelectPart.Column),
new XAttribute("ColumnName", matchingAddSelectPart.Column)));
}
}
}
}
public static EntityConnection Create(List<ColumnToModify> tablesAndColumns, string connString)
{
var modelNameRegex = new Regex(@".*metadata=res:\/\/\*\/([a-zA-Z.]*).csdl|.*");
var model = modelNameRegex.Matches(connString).Cast<Match>().SelectMany(o => o.Groups.Cast<Group>().Skip(1).Where(oo => oo.Value != "")).Select(o => o.Value).First();
var conceptualReader = XmlReader.Create(Assembly.GetExecutingAssembly().GetManifestResourceStream(model + ".csdl"));
var mappingReader = XmlReader.Create(Assembly.GetExecutingAssembly().GetManifestResourceStream(model + ".msl"));
var storageReader = XmlReader.Create(Assembly.GetExecutingAssembly().GetManifestResourceStream(model + ".ssdl"));
var conceptualXml = XElement.Load(conceptualReader);
var mappingXml = XElement.Load(mappingReader);
var storageXml = XElement.Load(storageReader);
foreach (var entitySet in new[] {storageXml, conceptualXml}.SelectMany(xml => xml.Elements()))
{
if (entitySet.Attribute("Name").Value == "ModelStoreContainer")
{
foreach (var entityContainerEntitySet in entitySet.Elements())
{
ModifyNodes(entityContainerEntitySet, tablesAndColumns);
}
}
ModifyNodes(entitySet, tablesAndColumns);
}
foreach (var entitySet in mappingXml.Elements().ElementAt(0).Elements())
{
if (entitySet.Name.LocalName == "EntitySetMapping")
{
foreach (var entityContainerEntitySet in entitySet.Elements().First().Elements())
{
ModifyNodes(entityContainerEntitySet, tablesAndColumns);
}
}
ModifyNodes(entitySet, tablesAndColumns);
}
var storageCollection = new StoreItemCollection(new [] {storageXml.CreateReader()});
var conceptualCollection = new EdmItemCollection(new[] { conceptualXml.CreateReader() });
var mappingCollection = new StorageMappingItemCollection(conceptualCollection, storageCollection, new[] {mappingXml.CreateReader()});
var workspace = new MetadataWorkspace();
workspace.RegisterItemCollection(conceptualCollection);
workspace.RegisterItemCollection(storageCollection);
workspace.RegisterItemCollection(mappingCollection);
var connectionData = new EntityConnectionStringBuilder(connString);
var connection = DbProviderFactories
.GetFactory(connectionData.Provider)
.CreateConnection();
connection.ConnectionString = connectionData.ProviderConnectionString;
return new EntityConnection(workspace, connection);
}
}
初始化：
public ActionResult QUOTE_HOUSE()
{
var onlineDocs = Enumerable.Empty<QUOTE_HOUSE>();
var mappings = new List<SagaSystemToDatabaseMapping>{new SagaSystemToDatabaseMapping("x", "Oracle", "Db1",
"metadata=res://*/Ecom.Ecom.csdl|res://*/Ecom.Ecom.ssdl|res://*/Ecom.Ecom.msl;provider=Oracle.ManagedDataAccess.Client;provider connection string='...'", typeof(EcomEntities))
{
ColumnsToModify = new List<ColumnToModify> { new ColumnToAdd("QUOTE_HOUSE","TESTCOL", typeof(string)) }
}};
var entityConnection = EntityConnectionExtensions.Create(mappings[0].ColumnsToModify,mappings[0].ConnectionString);
using (var db = new EcomEntities(entityConnection))
{
onlineDocs = db.QUOTE_HOUSE.Take(10);
}
return View("QUOTE_HOUSE", onlineDocs.ToList());
}
您应该能够从实体 QUOTE_HOUSE 生成 oracle 数据库并输入一些虚拟值，不要认为您需要一个视图，因为它在 .ToList() 上爆炸了。生成数据库后，向数据库添加其他列但不向模型添加列 (alter table QUOTE_HOUSE
add TESTCOL Varchar2(20)) - 使数据库中的列在运行时注入模型。您可能还需要调试 EF assemblies here's how to do it。如果您需要更多信息或者我遗漏了什么，请告诉我。
我知道这可能不是您所期望的，但我想至少它会帮助您避免在那个方向上浪费更多时间。
好消息是问题不是由您的 "hackish" 代码引起的。事实上，我能够在不使用该代码的情况下重现该问题。刚刚创建了一个包含 TestCol 的 QUOTE_HOUSE table，将其导入到新的 edmx 上下文中，并刚刚从实体 [=50= 中删除了生成的 TestCol 属性 ].然后我让 class 继承了 DynamicEntity，使用默认构造函数创建了一个名为 context.QUOTE_HOUSE.ToList() 的上下文，它因完全相同的异常而爆炸。
坏消息是你想要达到的目标是不可能的。 EF 仅使用反射来映射 "object space" 成员。它不提供任何类型扩展机制，例如 TypeDescriptor 或动态 运行time（它甚至不允许您投影到动态对象）。后者是可以理解的，因为每个动态对象可能具有不同的属性，并且没有动态type这样的东西。请注意，在 运行 时使用 "removing" 列的技巧是有效的，因为它所做的与首先在代码中使用 NotMapped 基本相同，即 属性 确实存在，但是被 EF 忽略。
如果您对为什么实体在 CSpace 但不在 OSpace 中感兴趣，答案包含在名为 OSpaceTypeFactory 的内部 class 中（在 System.Data.Entity.Core.Metadata.Edm 命名空间）- source。有一个方法叫做TryCreateStructuralType，它调用TryCreateMembers如果是returnsfalse，则不添加类型。 TryCreateMembers 轮流调用 TryFindAndCreatePrimitiveProperties，传递使用反射提取的 PropertyInfo 列表，如果不能映射 any[，则传递后面的 returns false =44=] CSpace 成员到 OSpace 对象 属性，从而有效地防止将类型添加到 OSpace 类型集合中。
希望至少能满足您的好奇心 :) 但是，不幸的是，"adding" 属性在 运行 时间到 EF 实体是一个死主意。