Unicode to ASCII string conversion

[Ger]

I have not been able to find a simple, straight forward Unicode to ASCII
string conversion function in VB.Net.
Is that because such a function does not exists or do I overlook it?

I found Encoding.Conver t, but that needs byte arrays.

Thanks,
/Ger

[Herfried K. Wagner [MVP]]

* "Ger" <ge*********@re move-this-part-of-address.planet. nl> scripsit:

I have not been able to find a simple, straight forward Unicode to ASCII
string conversion function in VB.Net.
Is that because such a function does not exists or do I overlook it?

'System.Text.En coding.ASCII.Ge tBytes',
'System.Text.En coding.Unicode. GetByte'.

BTW: Notice that there is no 1:1 mapping defined between Unicode and
ASCII, ASCII is 7-bit only and can thus only represent 128 characters.

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

[Jay B. Harlow [MVP - Outlook]]

Ger,
In addition to Herfried's comments.

For information on Unicode, ASCII and Encoding in .NET see:

http://www.yoda.arachsys.com/csharp/unicode.html

The samples may be in C#, however they should easily be converted to VB.NET

Hope this helps
Jay

"Ger" <ge*********@re move-this-part-of-address.planet. nl> wrote in message
news:up******** ******@TK2MSFTN GP09.phx.gbl...

I have not been able to find a simple, straight forward Unicode to ASCII
string conversion function in VB.Net.
Is that because such a function does not exists or do I overlook it?

I found Encoding.Conver t, but that needs byte arrays.

Thanks,
/Ger

[Ger]

Thanks Jay, a most useful document.
/Ger

"Jay B. Harlow [MVP - Outlook]" <Ja************ @msn.com> schreef in bericht
news:ee******** ******@TK2MSFTN GP11.phx.gbl...

Ger,
In addition to Herfried's comments.

For information on Unicode, ASCII and Encoding in .NET see:

http://www.yoda.arachsys.com/csharp/unicode.html

The samples may be in C#, however they should easily be converted to VB.NET
Hope this helps
Jay

"Ger" <ge*********@re move-this-part-of-address.planet. nl> wrote in message
news:up******** ******@TK2MSFTN GP09.phx.gbl...

I have not been able to find a simple, straight forward Unicode to ASCII
string conversion function in VB.Net.
Is that because such a function does not exists or do I overlook it?

I found Encoding.Conver t, but that needs byte arrays.

Thanks,
/Ger

[Ger]

"Herfried K. Wagner [MVP]" <hi************ ***@gmx.at> schreef in bericht
news:%2******** ********@TK2MSF TNGP10.phx.gbl. ..

* "Ger" <ge*********@re move-this-part-of-address.planet. nl> scripsit:

I have not been able to find a simple, straight forward Unicode to ASCII
string conversion function in VB.Net.
Is that because such a function does not exists or do I overlook it?

'System.Text.En coding.ASCII.Ge tBytes',
'System.Text.En coding.Unicode. GetByte'.

Thanks for your reply, but this returns a byte array. I ment straight
forward string-to-string conversion. It is possible ofcourse to write a
simple function to do this and using the encoding class, but I was just
wondering why the framework does not support the "direct string-to-string".
/Ger

[Cor Ligthert]

Ger,

Thanks for your reply, but this returns a byte array. I ment straight
forward string-to-string conversion. It is possible ofcourse to write a
simple function to do this and using the encoding class, but I was just
wondering why the framework does not support the "direct

string-to-string".

In the dotNet is a "String" is forever a string of unicode Chars. What you
call "ascii string" is forever a bytearray.

Therefore as an answer there is nothing more than Herfried suggested.
Although you can create an array of objects which contains bytes, however
that is no solution in my opinion.

I hope this helps to get the idea?

Cor

[Ger]

Ah, now I think I get the idea. So when I convert a (unicode) string into an
ascii byte array, and then the byte array back into a string, I still have
Unicode, right? So that is of no use when you want to write ASCII to a
filestream.

Is the code below then writing ASCII output to my filestream?

Dim UnicodeString As String = "abcdëfg"
Dim fsOutput as New FileStream(..)
Dim wOutput As New StreamWriter(fs Output, System.Text.Enc oding.ASCII)
wOutput.WriteLi ne(UnicodeStrin g)

Thank you for your reply.

/Ger
"Cor Ligthert" <no**********@p lanet.nl> schreef in bericht
news:eW******** ********@tk2msf tngp13.phx.gbl. ..

Ger,

Thanks for your reply, but this returns a byte array. I ment straight
forward string-to-string conversion. It is possible ofcourse to write a
simple function to do this and using the encoding class, but I was just
wondering why the framework does not support the "direct

string-to-string".

In the dotNet is a "String" is forever a string of unicode Chars. What you
call "ascii string" is forever a bytearray.

Therefore as an answer there is nothing more than Herfried suggested.
Although you can create an array of objects which contains bytes, however
that is no solution in my opinion.

I hope this helps to get the idea?

Cor

[Cor Ligthert]

Ger

Ah, now I think I get the idea. So when I convert a (unicode) string into an ascii byte array, and then the byte array back into a string, I still have
Unicode, right? So that is of no use when you want to write ASCII to a
filestream.

That I do not say, however when you read it back in a String you have again
a string of Chars.

http://msdn.microsoft.com/library/de...classtopic.asp

I hope this helps?

Cor

[Jay B. Harlow [MVP - Outlook]]

Ger,

Ah, now I think I get the idea. So when I convert a (Unicode) string into
an
ascii byte array, and then the byte array back into a string, I still have
Unicode, right? Correct, just remember that you will loose some characters going to & from
ASCII.
So that is of no use when you want to write ASCII to a
filestream. If you need an ASCII file, then use a ASCII encoding. It really depends on
what is going to read the file again.

I would recommend with an ANSI encoding (see below) or UTF8 encoding. With
ASCII you will loose all extended characters (ASCII is 7 bit encoding), with
ANSI you will loose characters that are outside of your regional ANSI code
page. UTF8 preserves all Unicode characters. I would recommend ANSI encoding
if the file was going to be opened by casual users in Notepad. I would
recommend UTF8 if full Unicode support is required. ANSI & UTF8 are both 8
bit encodings.

Is the code below then writing ASCII output to my filestream?
Yes that code is writing ASCII, as you included the ASCII encoding on the
StreamWriter constructor.

The text file itself will contain ASCII characters, when you subsequently
open that text stream and read it (with a StreamReader) it will be converted
back to Unicode strings. When reading the file back try to use the same
encoding as written. For example if you wrote ANSI, then use ANSI to read.
If you wrote UTF8, then use UTF8 to read. As ANSI & UTF8 encode characters
127 to 255 differently. Remember that Encoding.UTF8 is used on the stream
writer if you do not give one, if you are reading text files created by
Notepad, then you want Encoding.Defaul t.

I would recommend:
Dim wOutput As New StreamWriter(fs Output, System.Text.Enc oding.Default)
Which will write the file in your current ANSI code page as defined by the
regional settings in Windows Control Panel. Which will preserve extended
characters.

Remember that ANSI is an 8 bit encoding that is dependent on region (code
page). While ASCII is a 7 bit encoding, ASCII does not support extended
characters such as ë. It will be converted into either a normal e or a ?.

Hope this helps
Jay

"Ger" <ge*********@ra thernospam.sail soft.nl> wrote in message
news:uU******** ******@tk2msftn gp13.phx.gbl... Ah, now I think I get the idea. So when I convert a (unicode) string into
an
ascii byte array, and then the byte array back into a string, I still have
Unicode, right? So that is of no use when you want to write ASCII to a
filestream.

Is the code below then writing ASCII output to my filestream?

Dim UnicodeString As String = "abcdëfg"
Dim fsOutput as New FileStream(..)
Dim wOutput As New StreamWriter(fs Output, System.Text.Enc oding.ASCII)
wOutput.WriteLi ne(UnicodeStrin g)

Thank you for your reply.

/Ger
"Cor Ligthert" <no**********@p lanet.nl> schreef in bericht
news:eW******** ********@tk2msf tngp13.phx.gbl. ..

Ger,

> Thanks for your reply, but this returns a byte array. I ment straight
> forward string-to-string conversion. It is possible ofcourse to write a
> simple function to do this and using the encoding class, but I was just
> wondering why the framework does not support the "direct

string-to-string".

In the dotNet is a "String" is forever a string of unicode Chars. What
you
call "ascii string" is forever a bytearray.

Therefore as an answer there is nothing more than Herfried suggested.
Although you can create an array of objects which contains bytes, however
that is no solution in my opinion.

I hope this helps to get the idea?

Cor

[Ger]

Thank you very much guys for your help and clearing up the issue for me.
I will go for Jay's solution and use ANSI 8-bit.
/Ger

"Jay B. Harlow [MVP - Outlook]" <Ja************ @msn.com> schreef in bericht
news:%2******** ********@TK2MSF TNGP10.phx.gbl. ..

Ger,

Ah, now I think I get the idea. So when I convert a (Unicode) string into an
ascii byte array, and then the byte array back into a string, I still have Unicode, right? Correct, just remember that you will loose some characters going to & from
ASCII.

So that is of no use when you want to write ASCII to a
filestream.

If you need an ASCII file, then use a ASCII encoding. It really depends on
what is going to read the file again.

I would recommend with an ANSI encoding (see below) or UTF8 encoding. With
ASCII you will loose all extended characters (ASCII is 7 bit encoding),

with ANSI you will loose characters that are outside of your regional ANSI code
page. UTF8 preserves all Unicode characters. I would recommend ANSI encoding if the file was going to be opened by casual users in Notepad. I would
recommend UTF8 if full Unicode support is required. ANSI & UTF8 are both 8
bit encodings.

Is the code below then writing ASCII output to my filestream?
Yes that code is writing ASCII, as you included the ASCII encoding on the
StreamWriter constructor.

The text file itself will contain ASCII characters, when you subsequently
open that text stream and read it (with a StreamReader) it will be

converted back to Unicode strings. When reading the file back try to use the same
encoding as written. For example if you wrote ANSI, then use ANSI to read.
If you wrote UTF8, then use UTF8 to read. As ANSI & UTF8 encode characters
127 to 255 differently. Remember that Encoding.UTF8 is used on the stream
writer if you do not give one, if you are reading text files created by
Notepad, then you want Encoding.Defaul t.

I would recommend:

Dim wOutput As New StreamWriter(fs Output, System.Text.Enc oding.Default)

Which will write the file in your current ANSI code page as defined by the
regional settings in Windows Control Panel. Which will preserve extended
characters.

Remember that ANSI is an 8 bit encoding that is dependent on region (code
page). While ASCII is a 7 bit encoding, ASCII does not support extended
characters such as ë. It will be converted into either a normal e or a ?.

Hope this helps
Jay

"Ger" <ge*********@ra thernospam.sail soft.nl> wrote in message
news:uU******** ******@tk2msftn gp13.phx.gbl...

Ah, now I think I get the idea. So when I convert a (unicode) string into an
ascii byte array, and then the byte array back into a string, I still have Unicode, right? So that is of no use when you want to write ASCII to a
filestream.

Is the code below then writing ASCII output to my filestream?

Dim UnicodeString As String = "abcdëfg"
Dim fsOutput as New FileStream(..)
Dim wOutput As New StreamWriter(fs Output, System.Text.Enc oding.ASCII)
wOutput.WriteLi ne(UnicodeStrin g)

Thank you for your reply.

/Ger
"Cor Ligthert" <no**********@p lanet.nl> schreef in bericht
news:eW******** ********@tk2msf tngp13.phx.gbl. ..

Ger,

> Thanks for your reply, but this returns a byte array. I ment straight
> forward string-to-string conversion. It is possible ofcourse to write a > simple function to do this and using the encoding class, but I was just > wondering why the framework does not support the "direct
string-to-string".

In the dotNet is a "String" is forever a string of unicode Chars. What
you
call "ascii string" is forever a bytearray.

Therefore as an answer there is nothing more than Herfried suggested.
Although you can create an array of objects which contains bytes, however that is no solution in my opinion.

I hope this helps to get the idea?

Cor