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//---------------------------------------------------------------------
// <copyright file="NavigationProperty.cs" company="Microsoft">
// Copyright (c) Microsoft Corporation. All rights reserved.
// </copyright>
//
// @owner Microsoft
// @backupOwner Microsoft
//---------------------------------------------------------------------
namespace System.Data.EntityModel.SchemaObjectModel
{
using System.Data.Metadata.Edm;
using System.Diagnostics;
using System.Globalization;
using System.Xml;
/// <summary>
/// Summary description for Association.
/// </summary>
[System.Diagnostics.DebuggerDisplay("Name={Name}, Relationship={_unresolvedRelationshipName}, FromRole={_unresolvedFromEndRole}, ToRole={_unresolvedToEndRole}")]
internal sealed class NavigationProperty : Property
{
private string _unresolvedFromEndRole = null;
private string _unresolvedToEndRole = null;
private string _unresolvedRelationshipName = null;
private IRelationshipEnd _fromEnd = null;
private IRelationshipEnd _toEnd = null;
private IRelationship _relationship = null;
/// <summary>
///
/// </summary>
/// <param name="parent"></param>
public NavigationProperty(SchemaEntityType parent)
: base(parent)
{
}
/// <summary>
///
/// </summary>
public new SchemaEntityType ParentElement
{
get
{
return base.ParentElement as SchemaEntityType;
}
}
internal IRelationship Relationship
{
get { return _relationship; }
}
internal IRelationshipEnd ToEnd
{
get { return _toEnd; }
}
internal IRelationshipEnd FromEnd
{
get { return _fromEnd; }
}
/// <summary>
/// Gets the Type of the property
/// </summary>
public override SchemaType Type
{
get
{
if (_toEnd == null || _toEnd.Type == null)
{
return null;
}
return _toEnd.Type;
}
}
protected override bool HandleAttribute(XmlReader reader)
{
if (base.HandleAttribute(reader))
{
return true;
}
else if (CanHandleAttribute(reader, XmlConstants.Relationship))
{
HandleAssociationAttribute(reader);
return true;
}
else if (CanHandleAttribute(reader, XmlConstants.FromRole))
{
HandleFromRoleAttribute(reader);
return true;
}
else if (CanHandleAttribute(reader, XmlConstants.ToRole))
{
HandleToRoleAttribute(reader);
return true;
}
else if (CanHandleAttribute(reader, XmlConstants.ContainsTarget))
{
// EF does not support this EDM 3.0 attribute, so ignore it.
return true;
}
return false;
}
/// <summary>
///
/// </summary>
internal override void ResolveTopLevelNames()
{
base.ResolveTopLevelNames();
SchemaType element;
if (!Schema.ResolveTypeName(this, _unresolvedRelationshipName, out element))
return;
_relationship = element as IRelationship;
if (_relationship == null)
{
AddError(ErrorCode.BadNavigationProperty, EdmSchemaErrorSeverity.Error,
System.Data.Entity.Strings.BadNavigationPropertyRelationshipNotRelationship(_unresolvedRelationshipName));
return;
}
bool foundBothEnds = true;
if (!_relationship.TryGetEnd(_unresolvedFromEndRole, out _fromEnd))
{
AddError(ErrorCode.BadNavigationProperty, EdmSchemaErrorSeverity.Error,
System.Data.Entity.Strings.BadNavigationPropertyUndefinedRole(_unresolvedFromEndRole, _relationship.FQName));
foundBothEnds = false;
}
if (!_relationship.TryGetEnd(_unresolvedToEndRole, out _toEnd))
{
AddError(ErrorCode.BadNavigationProperty, EdmSchemaErrorSeverity.Error,
System.Data.Entity.Strings.BadNavigationPropertyUndefinedRole(_unresolvedToEndRole, _relationship.FQName));
foundBothEnds = false;
}
if (foundBothEnds && _fromEnd == _toEnd)
{
AddError(ErrorCode.BadNavigationProperty, EdmSchemaErrorSeverity.Error,
System.Data.Entity.Strings.BadNavigationPropertyRolesCannotBeTheSame);
}
}
/// <summary>
///
/// </summary>
internal override void Validate()
{
base.Validate();
System.Diagnostics.Debug.Assert(_fromEnd != null && _toEnd != null,
"FromEnd and ToEnd must not be null in Validate. ResolveNames must have resolved it or added error");
if (_fromEnd.Type != ParentElement)
{
AddError(ErrorCode.BadNavigationProperty, EdmSchemaErrorSeverity.Error,
System.Data.Entity.Strings.BadNavigationPropertyBadFromRoleType(this.Name,
_fromEnd.Type.FQName, _fromEnd.Name, _relationship.FQName, ParentElement.FQName));
}
StructuredType type = _toEnd.Type;
}
#region Private Methods
/// <summary>
///
/// </summary>
/// <param name="reader"></param>
private void HandleToRoleAttribute(XmlReader reader)
{
_unresolvedToEndRole = HandleUndottedNameAttribute(reader, _unresolvedToEndRole);
}
/// <summary>
///
/// </summary>
/// <param name="reader"></param>
private void HandleFromRoleAttribute(XmlReader reader)
{
_unresolvedFromEndRole = HandleUndottedNameAttribute(reader, _unresolvedFromEndRole);
}
/// <summary>
///
/// </summary>
/// <param name="reader"></param>
private void HandleAssociationAttribute(XmlReader reader)
{
Debug.Assert(_unresolvedRelationshipName == null, string.Format(CultureInfo.CurrentCulture, "{0} is already defined", reader.Name));
string association;
if (!Utils.GetDottedName(this.Schema, reader, out association))
return;
_unresolvedRelationshipName = association;
}
#endregion
}
}
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