Class BaseEntity

The base class that every system implementation of IBaseEntity inherits from

Inheritance

System.Object

BaseEntity

BaseEntityWithPermissions

Implements

IBaseEntity

System.IEquatable<IBaseEntity>

ICanTrackProperties

System.ComponentModel.INotifyPropertyChanging

System.ComponentModel.INotifyPropertyChanged

ICloneableAsync

Inherited Members

System.Object.Equals(System.Object, System.Object)

System.Object.GetType()

System.Object.MemberwiseClone()

System.Object.ReferenceEquals(System.Object, System.Object)

System.Object.ToString()

Namespace: LemonEdge.API.Core

Assembly: API.dll

Syntax

[DataContract]
public abstract class BaseEntity : IBaseEntity, IEquatable<IBaseEntity>, ICanTrackProperties, INotifyPropertyChanging, INotifyPropertyChanged, ICloneableAsync

Remarks

If using our auto-code designers, or other tools the system will always create entities for you that inherit this base class. These correctly implement all the LemonEdge technology such as the following interfaces:

• entityUpdateContext: Holds an instance of IEntityUpdater
• IBaseEntity: The base entity interface implementation
• System.ComponentModel.INotifyPropertyChanging: Ensures all property changes are correctly raised to listeners
• System.ComponentModel.INotifyPropertyChanged: Ensures all property changes are correctly raised to listeners
• ICloneableAsync: Ensures this entity can be cloned, and have all its property values copied

You are however free to completely implement your own base class as long as it implements all the required interfaces

Fields

HISTORY_ENDROWUPDATE_COLNAME

The name reserved by the system for the column holding change dates for the auditing table

For every entity in the system that has a table created in the database, it also has an associated audit table

Declaration

public const string HISTORY_ENDROWUPDATE_COLNAME = "EndUpdated"

Field Value

Type	Description
System.String

Properties

AccountID

LemonEdge is a multi-tenanted system, and thus you can have several different accounts all residing in the same database

The default root account is 1

This property holds the account the item belongs to. It can not be modified by a user, it is maintained internally by the system

Declaration

public long AccountID { get; set; }

Property Value

Type	Description
System.Int64

CanvasID

If this record is within a canvas, this holds the canvas id for the record.

By ensuring all items in the system have a canvas property, we can guarantee a mechanism for isolating canvases and ensuring all entities are compatabile with them

Declaration

public Guid? CanvasID { get; set; }

Property Value

Type	Description
System.Nullable<System.Guid>

CanvasID_Label

If this record is within a canvas, this holds the canvas label for the record

Declaration

public string CanvasID_Label { get; set; }

Property Value

Type	Description
System.String

ID

All items in the system have a globally unique id.

This is used instead of auto-increment numbers for several reasons, but the main one being it enables all entities to be designed to cope with importing/exporting/copying. It is very easy to create an entire copy of an account into another one by maintaining the same ids

Declaration

public Guid ID { get; set; }

Property Value

Type	Description
System.Guid

LastUpdated

The server datetime stamps of when this item was last udpated in the system

By ensuring every record has a datetimestamp for changes, and by keeping all old records, we can ensure the entire system can be ran as of any point in time in the past

Declaration

public DateTimeOffset LastUpdated { get; set; }

Property Value

Type	Description
System.DateTimeOffset

Remarks

We should always use datetimeoffsets. They are international, with time zones, but most importantly odata supports them and not datetime

ModifiedByUserID

This holds the id of the user that made the change to the item

Declaration

public Guid ModifiedByUserID { get; set; }

Property Value

Type	Description
System.Guid

ModifiedByUserID_Label

This holds the name of the user that made the change to the item

Declaration

public string ModifiedByUserID_Label { get; set; }

Property Value

Type	Description
System.String

TrackChanges

By default, no changes are tracked. Only services directly connecting to the db should track property changes.

Declaration

public static bool TrackChanges { get; set; }

Property Value

Type	Description
System.Boolean

Methods

AddTrackedOriginalValue(String, Object)

Should be called whenever a tracked property has its value changed. This ensures the original value is tracked along with the fact it has changed.

Declaration

protected void AddTrackedOriginalValue(string propName, object value)

Parameters

Type	Name	Description
System.String	propName
System.Object	value

ClearTrackedOriginalValues()

Clears all records of the tracked changes against this entity.

Note: It does *not* reset any changed values back to their original values (ResetChangedTrackedPropertiesToOriginalValues() does that), it simply clears the tracking of those changes

Declaration

public void ClearTrackedOriginalValues()

Clone(Object)

ICloneableAsync implementation - Creates a new instance of this class with all the same property values as this instance

Declaration

public Task<object> Clone(object context)

Parameters

Type	Name	Description
System.Object	context	A context item used for creating a new instance of this item. Can allow permission checks and other functionality.

Returns

Type	Description
System.Threading.Tasks.Task<System.Object>	A task that creates new instance of this class with all the same property values as this instance

CopyFromEntity(IBaseEntity)

Declaration

protected virtual void CopyFromEntity(IBaseEntity source)

Parameters

Type	Name	Description
IBaseEntity	source

CopyFromSource(Object)

ICloneableAsync implementation - Updates all properties in this item to have the same properties as the source object.

The source object should be of the same type as this one

Declaration

public void CopyFromSource(object source)

Parameters

Type	Name	Description
System.Object	source	The source object to copy all values from. Should be of the same type as this one.

Equals(IBaseEntity)

IEquatable implementation of Equals, evaluating if the ID matches

Declaration

public virtual bool Equals(IBaseEntity other)

Parameters

Type	Name	Description
IBaseEntity	other	The other IBaseEntity to compare on IDs

Returns

Type	Description
System.Boolean	True if the IDs match

Equals(Object)

IEquatable implementation of Equals, evaluating if the ID matches

Declaration

public override bool Equals(object obj)

Parameters

Type	Name	Description
System.Object	obj	The other IBaseEntity to compare on IDs

Returns

Type	Description
System.Boolean	True if the IDs match

Overrides

System.Object.Equals(System.Object)

GetAllOriginalTrackedPropertyValues()

For all properties that are marked to track values (indicated with DBTrackChangesAttribute), this returns the a dictionary of property name and associated original unchanged value for properties that have had their value changed

Declaration

public IReadOnlyDictionary<string, object> GetAllOriginalTrackedPropertyValues()

Returns

Type	Description
System.Collections.Generic.IReadOnlyDictionary<System.String, System.Object>	A dictionary of property name and associated original value for properties that have had their value changed

GetHashCode()

Returns a hashcode for this entity based on the ID

Declaration

public override int GetHashCode()

Returns

Type	Description
System.Int32	A hashcode for this entity based on the ID

Overrides

System.Object.GetHashCode()

GetLabel(String)

For properties that are Guid properties holding a relationship to another entity, this function returns the label held for that id

This is done by the class that implements this interface holding a xxx_Label property for every xxx Guid relationship property with a label

Declaration

public string GetLabel(string propName)

Parameters

Type	Name	Description
System.String	propName	The Guid relationship property name to return the label for that item of

Returns

Type	Description
System.String	The label held for the specified guid relationship property

HasTrackedPropertyChanged(String)

Indicates if a tracked property (indicated with DBTrackChangesAttribute) has had its value changed

Declaration

public bool HasTrackedPropertyChanged(string propName)

Parameters

Type	Name	Description
System.String	propName	The name of the property to check if its value has changed

Returns

Type	Description
System.Boolean	True if a tracked property (indicated with DBTrackChangesAttribute) has had its value changed

IsBasePropertyName(String)

Returns true if the specified property name is one of the core base properties specified in IBaseEntity

Declaration

public static bool IsBasePropertyName(string name)

Parameters

Type	Name	Description
System.String	name	The name of the property on an entity

Returns

Type	Description
System.Boolean	True if the specified property name is one of the core base properties specified in IBaseEntity

IsBaseRelationshipID(String)

Returns true if the specified property is one of the core base properties specified in IBaseEntity that is a relationship property

Declaration

public static bool IsBaseRelationshipID(string name)

Parameters

Type	Name	Description
System.String	name	The name of the property on an entity

Returns

Type	Description
System.Boolean	True if the specified property is one of the core base properties specified in IBaseEntity that is a relationship property

OnPropertyChanged(String)

Notifies any System.ComponentModel.INotifyPropertyChanged listeners

Declaration

protected virtual void OnPropertyChanged(string propName)

Parameters

Type	Name	Description
System.String	propName	The property that is changing its value

OnPropertyChanging(String)

Notifies any System.ComponentModel.INotifyPropertyChanging listeners

Declaration

protected void OnPropertyChanging(string propName)

Parameters

Type	Name	Description
System.String	propName	The property that is changing its value

OriginalTrackedPropertyValue(String)

Returns the original value of a property that has its value tracked (indicated with DBTrackChangesAttribute) before any changes

Declaration

public object OriginalTrackedPropertyValue(string propName)

Parameters

Type	Name	Description
System.String	propName	The name of the property to return the original value for

Returns

Type	Description
System.Object	The original value of a property that has its value tracked (indicated with DBTrackChangesAttribute) before any changes

Remarks

Will throw an error if the property has not changed value and still has its original value

OriginalTrackedPropertyValue<T>(String)

Returns the original value of a property that has its value tracked (indicated with DBTrackChangesAttribute) before any changes

Declaration

public T OriginalTrackedPropertyValue<T>(string propName)

Parameters

Type	Name	Description
System.String	propName	The name of the property to return the original value for

Returns

Type	Description
T	The original value of a property that has its value tracked (indicated with DBTrackChangesAttribute) before any changes

Type Parameters

Name	Description
T	The type to return the property value as. Should match the actual type of the property.

Remarks

Will throw an error if the property has not changed value and still has its original value

ResetChangedTrackedPropertiesToOriginalValues()

For each tracked property (indicated with DBTrackChangesAttribute) that has had its value changed this will reset that change back to the original value and then call ClearTrackedOriginalValues()

Declaration

public Dictionary<string, object> ResetChangedTrackedPropertiesToOriginalValues()

Returns

Type	Description
System.Collections.Generic.Dictionary<System.String, System.Object>	A snapshot of all the values that were changed before they are reset -> the property name and its changed value

RestoreFromSnapshot(Dictionary<String, Object>)

Restores all properties for this entity using the provided dictionary of property name and values

Declaration

public void RestoreFromSnapshot(Dictionary<string, object> snapshot)

Parameters

Type	Name	Description
System.Collections.Generic.Dictionary<System.String, System.Object>	snapshot	A complete list of all properties and associated values

SetLabel(String, String)

For properties that are Guid properties holding a relationship to another entity, this function can be used to set the label held for that id

This is used throughout the client UI by the platform to update the labels held when users choose different items for relationships so the UI immediately reflects these choices

This is done by the class that implements this interface holding a xxx_Label property for every xxx Guid relationship property with a label

Declaration

public void SetLabel(string propName, string value)

Parameters

Type	Name	Description
System.String	propName	The Guid relationship property name to update the label for that item of
System.String	value	The new label value for the corrosponding property id

SetSilentLabel(String, String)

The same as SetLabel(String, String) except done without raising any System.ComponentModel.INotifyPropertyChanged events

Declaration

public void SetSilentLabel(string propName, string value)

Parameters

Type	Name	Description
System.String	propName	The Guid relationship property name to update the label for that item of
System.String	value	The new label value for the corrosponding property id

SnapshotProperties()

Returns a snap shot of all the property values against this entity as a dictionary of property name/value

Declaration

public Dictionary<string, object> SnapshotProperties()

Returns

Type	Description
System.Collections.Generic.Dictionary<System.String, System.Object>	A snap shot of all the property values against this entity as a dictionary of property name/value

Events

PropertyChanged

System.ComponentModel.INotifyPropertyChanged Implementation

Declaration

public event PropertyChangedEventHandler PropertyChanged

Event Type

Type	Description
System.ComponentModel.PropertyChangedEventHandler

PropertyChanging

System.ComponentModel.INotifyPropertyChanging Implementation

Declaration

public event PropertyChangingEventHandler PropertyChanging

Event Type

Type	Description
System.ComponentModel.PropertyChangingEventHandler

Implements

IBaseEntity

System.IEquatable<T>

ICanTrackProperties

System.ComponentModel.INotifyPropertyChanging

System.ComponentModel.INotifyPropertyChanged

ICloneableAsync

Extension Methods

MiscExtensions.SetIfNotEqual<T, P>(T, Expression<Func<T, P>>, P)

ReflectionExtensions.ClearEventInvocations(Object, String)

StringExtensions.ToCSVFormatString(Object, Type)

SQLExtensions.ToSQLValue(Object, Boolean)