Please explain the memory leak in the managed code with an example?

Question

I was asked this question in an interview: how does a memory leak problem occur in C # since everyone knows that the garbage collector is responsible for all the memory management work? So how is this possible?

Answer 1

From MSDN : -

A memory leak occurs when memory is allocated in a program and never returned to the operating system, even if the program does not use memory anymore. The four main types of memory leaks are listed below:

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 Dim DS As DataSet
  Dim cn As New SqlClient.SqlConnection("data source=localhost;initial catalog=Northwind;integrated security=SSPI")
  cn.Open()

  Dim da As New SqlClient.SqlDataAdapter("Select * from Employees", cn)
  Dim i As Integer
  DS = New DataSet()

  For i = 0 To 1000
      da.Fill(DS, "Table" + i.ToString)
  Next

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Answer 2

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.

Answer 3

- Child, ClickEventHandler, ClickEvent Parent.

GC Child , Parent . Child , GC , Parent

---

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,

Broadcaster(ClickEvent) -> Subscribers(ClickEventHandler)

GC ClickEventHandlers , ClickEvent !

Answer 4

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Popups [] collectionOfPopups. .

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, GC http://msdn.microsoft.com/en-us/library/ee787088.aspx

.

Answer 5

There may be several reasons, but here is one of them:

Consider two classes:

class A
{
  private B b;
}

class B
{
  private A a;
}

If you create an object for each of these classes and cross them, and after that both of these objects go out of scope, you will still have a link to each of them in the other. The GC is very difficult to catch these kinds of cross-references, and it may continue to believe that both objects are still in use.