Determinate whether a 'Char' is null

[Xero]

How do you determinate whether a varible of data type 'Char' is null or not?

I used the following code, but it seemed that it didn't work:

Dim ans As Char
If ans = "" Then
MsgBox("Ans contains no value")
Else
MsgBox("Ans contains a value")
End If

Thanks.
--
Xero

http://www.chezjeff.net
My personal web portal

[Hal Rosser]

"Xero" <jeff_@_chezjeff_._net(remove_underscores_and_this )> wrote in message
news:19**********************************@microsof t.com...

How do you determinate whether a varible of data type 'Char' is null or not?
I used the following code, but it seemed that it didn't work:

Dim ans As Char
If ans = "" Then
MsgBox("Ans contains no value")
Else
MsgBox("Ans contains a value")
End If

Thanks.
--

if you put it in quotes, then its a string - not char.
try
if ans = toChar("") then
....etc...

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[Shiva]

Try: If ans = CType ("", Char) Then

"Xero" <jeff_@_chezjeff_._net(remove_underscores_and_this )> wrote in message
news:19**********************************@microsof t.com...
How do you determinate whether a varible of data type 'Char' is null or not?

I used the following code, but it seemed that it didn't work:

Dim ans As Char
If ans = "" Then
MsgBox("Ans contains no value")
Else
MsgBox("Ans contains a value")
End If

Thanks.
--
Xero

http://www.chezjeff.net
My personal web portal

[Mattias Sjögren]

How do you determinate whether a varible of data type 'Char' is null or not?

A Char variable can't be "null" since Char is a value type. The
default value of a Char variable is zero, and you can test it with

If ans = ChrW(0) Then

or

If ans = ControlChars.NullChar Then

Mattias

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Mattias Sjögren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.

[Xero]

Thanks very much :)

Xero
"Shiva" wrote:

Try: If ans = CType ("", Char) Then

"Xero" <jeff_@_chezjeff_._net(remove_underscores_and_this )> wrote in message
news:19**********************************@microsof t.com...
How do you determinate whether a varible of data type 'Char' is null or not?

I used the following code, but it seemed that it didn't work:

Dim ans As Char
If ans = "" Then
MsgBox("Ans contains no value")
Else
MsgBox("Ans contains a value")
End If

Thanks.
--
Xero

http://www.chezjeff.net
My personal web portal

[Cor Ligthert]

Jeff,

AFAIK can you test every value type for its initial value with

If x = nothing

I hope this helps?

Cor

"Xero" <jeff_@_chezjeff_._net(remove_underscores_and_this )>

How do you determinate whether a varible of data type 'Char' is null or
not?

I used the following code, but it seemed that it didn't work:

Dim ans As Char
If ans = "" Then
MsgBox("Ans contains no value")
Else
MsgBox("Ans contains a value")
End If

Thanks.
--
Xero

http://www.chezjeff.net
My personal web portal

[Herfried K. Wagner [MVP]]

"Shiva" <sh******@online.excite.com> schrieb:

Try: If ans = CType ("", Char) Then

A nullchar is different from a string of length 0.

Use 'ControlChars.NullChar'/'vbNullChar'/'ChrW(0)' instead.

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>