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In my VB6 application I have an array of objects declared thus...
Dim MyArray() as MyClass
This array is filled in as processing goes on
Set MyArray(element) = passed_object
and as elements are no longer wanted,
Set MyArray(otherelement) = Nothing
When using the array, I want to use a loop like
For i = 1 To Ubound(MyArray)
If MyArray(i) <> Nothing Then ' Doesn't compile
...do something...
End If
Next i
But I can't get anything likely-looking to compile. I've also tried
If MyArray(i) Is Not Nothing Then
Should I want to do this, and if so, what test should I put in here?
331
When checking whether a reference (or nullable value type) variable is null , do not use = Nothing or <> Nothing . Always use Is Nothing or IsNot Nothing . For strings in Visual Basic, the empty string equals Nothing .
In mathematics, the word null (from German: null meaning "zero", which is from Latin: nullus meaning "none") is often associated with the concept of zero or the concept of nothing. It is used in varying context from "having zero members in a set" (e.g., null set) to "having a value of zero" (e.g., null vector).
In Visual Basic 6.0, the Null keyword indicated that a field contained no valid data, and the IsNull function was used to test for Null. In addition, Visual Basic 6 supported Null propagation when Null was used in an expression, the result of the expression would also be Null.
VB.Net IsNothing Function returns a Boolean value indicating whether an expression has no object assigned to it. There is no direct, 100% equivalent of the Vb.Net function IsNothing, but the test against null accomplishes the same thing.
If Not MyArray(i) Is Nothing Then
If Not MyArray(i) Is Nothing Then
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