检查 VBA 中的变体是否为空
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Check if variant is null in VBA
提问by Vignesh Subramanian
I am passing a variant as parameter into a function
我将一个变体作为参数传递给一个函数
For simplicity I have put up this sample functions to explain my situation
为简单起见，我提出了这个示例函数来解释我的情况
Public Function test()
Dim arr() As String
testing (arr)
End Function
Public Function testing(ar As Variant)
If ar = Empty Then
MsgBox ("Hello")
End If
End Function
Sometimes the FilesDetailswill be null, during that time the function is returning "For loop not initialized" error
有时FilesDetails会null，在此期间，该函数返回“ For loop not initialized”错误
How can I check if the variant is null?
如何检查变体是否为空？
I tried UBound(FilesDetails), FilesDetails.Count,IsNull(FilesDetails)but no luck
我试过了，UBound(FilesDetails), FilesDetails.Count,IsNull(FilesDetails)但没有运气
回答by Vignesh Subramanian
I solved it by using the below method
我用下面的方法解决了
Public Function test()
Dim Arr(1) As String
Arr(0) = "d"
Dim x As Boolean
x = IsArrayAllocated(Arr)
End Function
Function IsArrayAllocated(Arr As Variant) As Boolean
On Error Resume Next
IsArrayAllocated = IsArray(Arr) And _
Not IsError(LBound(Arr, 1)) And _
LBound(Arr, 1) <= UBound(Arr, 1)
End Function
The isArrayAllocated function returns true if its not null
isArrayAllocated 函数如果不为 null 则返回 true
回答by daniele3004
Try this :-)
尝试这个 ：-）
Dim var As Variant
If var = Empty Then
MsgBox "Variant data is Empty"
End If
or
或者
If IsEmpty(var) Then
MsgBox "Variant data is Empty"
End If
回答by daniele3004
Try this:
尝试这个：
Public Function test()
Dim arr() As String
testing (arr)
End Function
Public Function testing(ar As Variant)
If arr = "" Then
MsgBox ("Hello")
End If
End Function
