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<h1><a name="kanchor34"></a>Delete Behavior</h1>
<p>Deleting an object is as simple as storing an object. You simply call the delete-method on the container to delete it. By default only the object you pass to the delete method is deleted. All referenced objects are not deleted.</p>
<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">Car car = FindCar(container);
container.Delete(car);
// We've deleted the only care there is
AssertEquals(0, AllCars(container).Count);
// The pilots are still there
AssertEquals(1, AllPilots(container).Count);</pre>
<div class="codesnippet-meta">DeletionExamples.cs: Deleting object is as simple as storing
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Dim car As Car = FindCar(container)
container.Delete(car)
' We've deleted the only care there is
AssertEquals(0, AllCars(container).Count)
' The pilots are still there
AssertEquals(1, AllPilots(container).Count)</pre>
<div class="codesnippet-meta">DeletionExamples.vb: Deleting object is as simple as storing
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<h2>Reference To Deleted Objects</h2>
<p>What happens when you delete a object which is still referenced by other objects? Well in such cases that reference is set to null.</p>
<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">Pilot pilot = FindPilot(container);
container.Delete(pilot);</pre>
<div class="codesnippet-meta">DeletionExamples.cs: Delete the pilot
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">Dim pilot As Pilot = FindPilot(container)
container.Delete(pilot)</pre>
<div class="codesnippet-meta">DeletionExamples.vb: Delete the pilot
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<div class="codesnippet" MadCap:conditions="Primary.c#">
<pre class="prettyprint" xml:space="preserve">// Now the car's reference to the car is set to null
Car car = FindCar(container);
AssertEquals(null, car.Pilot);</pre>
<div class="codesnippet-meta">DeletionExamples.cs: Reference is null after deleting
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<div class="codesnippet" MadCap:conditions="Primary.VB.NET">
<pre class="prettyprint lang-vb" MadCap:conditions="Primary.Online" xml:space="preserve">' Now the car's reference to the car is set to null
Dim car As Car = FindCar(container)
AssertEquals(Nothing, car.Pilot)</pre>
<div class="codesnippet-meta">DeletionExamples.vb: Reference is null after deleting
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<p>Often you want to ensure that a object isn't referenced anymore, before you can delete it. However such referential integrity isn't supported at the moment. You need to implement your integrity checks manually, for example with <a href="../advanced_topics/callbacks.htm">callbacks</a>. </p>
<h2>Cascading Deletion And Collections.</h2>
<p>Additionally you can configure cascading behavior for deletion. <a href="delete_behavior/cascading_deletion.htm" target="" title="" alt="" class="MCXref" xrefformat="See "{paratext}"">See "Cascading Deletion"</a></p>
<p>Also collections are treated like regular objects and need to be deleted explicitly. <a href="delete_behavior/collections.htm" target="" title="" alt="" class="MCXref" xrefformat="See "{paratext}"">See "Collections And Arrays"</a></p>
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