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copied!<p><strong>Microsoft Reference:</strong></p> <p><a href="http://msdn.microsoft.com/en-gb/library/cc853327.aspx" rel="nofollow noreferrer">http://msdn.microsoft.com/en-gb/library/cc853327.aspx</a></p> <p>They say;</p> <blockquote> <p>Limit the scope of the ObjectContext</p> <p>In most cases, you should create an ObjectContext instance within a using statement (Using…End Using in Visual Basic). </p> <p>This can increase performance by ensuring that the resources associated with the object context are disposed automatically when the code exits the statement block. </p> <p>However, when controls are bound to objects managed by the object context, the ObjectContext instance should be maintained as long as the binding is needed and disposed of manually. </p> <p>For more information, see Managing Resources in Object Services (Entity Framework). <a href="http://msdn.microsoft.com/en-gb/library/bb896325.aspx" rel="nofollow noreferrer">http://msdn.microsoft.com/en-gb/library/bb896325.aspx</a></p> </blockquote> <p>Which says;</p> <blockquote> <p>In a long-running object context, you must ensure that the context is disposed when it is no longer required.</p> </blockquote> <hr> <p><strong>StackOverflow Reference:</strong></p> <p>This StackOverflow question also has some useful answers... </p> <p><a href="https://stackoverflow.com/questions/3957485/entity-framework-best-practices-in-business-logic">Entity Framework Best Practices In Business Logic?</a></p> <p>Where a few have suggested that you promote your context to a higher level and reference it from here, thus keeping only one single Context.</p> <hr> <p><strong>My ten pence worth:</strong></p> <p>Wrapping the Context in a Using Statement, allows the Garbage Collector to clean up the resources, and prevents memory leaks.</p> <p>Obviously in simple apps, this isn't much of a problem, however, if you have multiple screens, all using alot of data, you could end up in trouble, unless you are certain to Dispose your Context correctly.</p> <p>Hence I have employed a similar method to the one you have mentioned, where I've added an <code>AddOrUpdate</code> Method to each of my Repositories, where I pass in my New or Modified Entity, and Update or Add it depending upon whether it exists.</p> <hr> <p><strong>Updating Entity Properties:</strong></p> <p>Regarding updating properties however, I've used a simple function which uses reflection to copy all the properties from one Entity to Another;</p> <pre><code>Public Shared Function CopyProperties(Of sourceType As {Class, New}, targetType As {Class, New})(ByVal source As sourceType, ByVal target As targetType) As targetType Dim sourceProperties() As PropertyInfo = source.GetType().GetProperties() Dim targetProperties() As PropertyInfo = GetType(targetType).GetProperties() For Each sourceProp As PropertyInfo In sourceProperties For Each targetProp As PropertyInfo In targetProperties If sourceProp.Name <> targetProp.Name Then Continue For ' Only try to set property when able to read the source and write the target ' ' *** Note: We are checking for Entity Types by Checking for the PropertyType to Start with either a Collection or a Member of the Context Namespace! ' If sourceProp.CanRead And _ targetProp.CanWrite Then ' We want to leave System types alone If sourceProp.PropertyType.FullName.StartsWith("System.Collections") Or (sourceProp.PropertyType.IsClass And _ sourceProp.PropertyType.FullName.StartsWith("System.Collections")) Or sourceProp.PropertyType.FullName.StartsWith("MyContextNameSpace.") Then ' ' Do Not Store ' Else Try targetProp.SetValue(target, sourceProp.GetValue(source, Nothing), Nothing) Catch ex As Exception End Try End If End If Exit For Next Next Return target End Function </code></pre> <p>Where I do something like;</p> <pre><code>dbColour = Classes.clsHelpers.CopyProperties(Of Colour, Colour)(RecordToSave, dbColour) </code></pre> <p>This reduces the amount of code I need to write for each Repository of course!</p>

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