Class

OutOfMemoryException

Description

This exception is raised in certain cases when there is not enough available memory for the requested action.

Properties

Name	Type	Read-Only	Shared
ErrorNumber	Integer
Message	String

Methods

Name	Parameters	Returns
Constructor	message As String = "", errorCode As Integer = 0
Stack		String
StackFrames		StackFrame

Property descriptions

OutOfMemoryException.ErrorNumber

ErrorNumber As Integer

Used to contain an error number that describes the runtime error.

The following example displays a message box if, for example, you try to create more than one KeychainItem for the same application.

Var newItem As KeychainItem
If System.KeychainCount > 0 Then
  newItem = New KeychainItem
  // Indicate the name of the application
  newItem.ServiceName = "MyApplication"

  // Create a new keychain item for the application and assign the password
  System.Keychain.AddPassword(newItem, "SecretPassword")
Else
  System.Beep
  MessageBox("You don't have a key chain.")
End If
Exception err As KeychainException
  MessageBox(err.Message + ". Error Code: " + err.ErrorNumber.ToString)

OutOfMemoryException.Message

Message As String

Used to contain descriptive text to display when the runtime exception is encountered.

The following example displays a message box if, for example, you try to create more than one KeychainItem for the same application.

Var newItem As KeyChainItem
If System.KeyChainCount > 0 Then
  newItem = New KeyChainItem
  // Indicate the name of the application
  newItem.ServiceName = "MyApplication"

  // Create a new keychain item for the application and assign the password
  System.KeyChain.AddPassword(newItem, "SecretPassword")
Else
  System.Beep
  MessageBox("You don't have a key chain.")
End If
Exception err As KeyChainException
  MessageBox(err.Message + ". Error Code: " + err.ErrorNumber.ToString)

Method descriptions

OutOfMemoryException.Constructor

Constructor(message As String = "", errorCode As Integer = 0)

Note

Constructors are special methods called when you create an object with the New keyword and pass in the parameters above.

Used to raise your own RuntimeException with a message and optional error code.

OutOfMemoryException.Stack

Stack As String

Returns a String array that contains a list of all of the methods in the stack from the main entrypoint to the point at which the exception was invoked.

The stack contains all the method names up and including the current method name.

This feature only works if the IncludeFunctionNames property on the App object is selected in the Shared Build Settings.

In addition to your own method calls, you will also see framework method calls, but these may not always be completely accurate due to insufficient symbols for the OS to resolve.

OutOfMemoryException.StackFrames

StackFrames As StackFrame

Returns an array containing the stack when the exception was first raised.

Notes

This exception is mostly useful with MemoryBlock and Picture when attempting to allocate large blocks of memory that would exceed the remaining available memory.

Low-level memory situations are inherently problematic, especially if you are frequently requesting small blocks of memory (using MemoryBlock or Picture). Because of this, there is no guarantee that an OutOfMemoryException can even be raised. If the system memory has gotten critically low, the process itself may crash as it attempts to reserve memory in order to display an exception message.

In this situation, you might consider reserving a large block of memory up front and using that within your application rather than repeatedly requesting smaller blocks.

Sample code

This example uses the Catch statement in a window's Opening event handler to handle out of memory exceptions when trying to draw an imported gif image. The variable myPicture is a global property of type Picture. The picture "Logo" has been added to the Project Editor.

Sub Opening
Try
  myPicture = New Picture(Logo.Width, Logo.Height)
  myPicture.Graphics.DrawPicture(Logo, 0, 0)
Catch err As OutOfMemoryException
  MessageBox("Insufficient memory to draw the picture!")
  Quit
End Try

Compatibility

All project types on all supported operating systems.