Re: Converting a unicode value (with a surrogate pair) to a character in C# - C# Discussion Boards

Re: Converting a unicode value (with a surrogate pair) to a character in C#

31-Dec-10 7:52

gordon_matt wrote:
I want to know how to get the correct character from a unicode value which has a surrogate key. For example:

The data type 'char' only has 16 bits.

For C# the full range of unicode characters extends to 10FFFF, which will not fit in a 'char'.

The char represents a code point not a character in the full range of unicode character set.

A surrogate pair is by definition two code points. So to represent it you must have two 'char' values.
Alternatives would be to use an 'int' or a String.

vnmatt31-Dec-10 17:39

vnmatt

31-Dec-10 17:39

Thanks for the reply. I understand this well enough, but maybe everyone here is not quite understanding what I want...

Okay don't return a System.Char... give me a System.String...whatever....

I just want to do something like this:

public string GetUnicodeCharacter(string uniValue)
{
//uniValue = "U+2A601"
//Do some logic
return myUnicodeCharacter; //string that will display 𪘁
}

It seems nobody knows how to get this and it is driving me nuts. Yes I did email the author of that site (cojak.org), but no reply yet; maybe because of holidays, but I'll be lucky if he helps me anyway (not to mention his site is PHP, so might not be able to help with .NET).

Maybe there is a way to get the surrogate values from the "U+2A601" string? Then I could do something (ugly as it may be) like this:

public string myImaginaryMethod()
{
   string original = "\u2A601";
   string highSurrogate = GetHighSurrogate(original); // returns "\uD869";
   string lowSurrogate = GetLowSurrogate(original); returns "\uDE01";
   return highSurrogate + lowSurrogate; //returns 𪘁
}

Surely someone must know how to get this value somehow...anyhow...I don't care how, so long as I can get 𪘁 from "U+2A601"; (or from "\u2A601" would be fine too)

Smile | :)

Re: Converting a unicode value (with a surrogate pair) to a character in C#

jschell1-Jan-11 10:04

Re: Converting a unicode value (with a surrogate pair) to a character in C#

1-Jan-11 10:04

gordon_matt wrote:
It seems nobody knows how to get this and it is driving me nuts

Mentioning the surrogate pair probably confused the issue. It certainly did for me.

The following code should be what you want (with appropriate bit manipulation.) If not then could you provide the unicode.org page reference for 2A601 (I couldn't find it.)

// 2A601
byte[] array = new byte[4];
int i=0;
array[i++] = (byte)0x0001; // Little endian
array[i++] = (byte)0x00A6;
array[i++] = (byte)0x0002;
array[i++] = (byte)0x0000;

String r = System.Text.Encoding.UTF32.GetString(array);

vnmatt1-Jan-11 18:23

vnmatt

1-Jan-11 18:23

Thanks jschell. What Richard mentioned about it being 20 bits got me thinking this must be a UTF-32 character and after a LOT of research, I finally got the answer I needed and the solution is actually quite simple once you know what to look for:

If you pass in "U+2A601" to this method of mine, you'll get the correct character returned. I think I may go ahead and post a tip/trick on this Smile | :)

Thanks to all for helping point me in the right direction.

public static string ConvertUnicodeToCharacter(string unicodeValue)
        {
            int unicode = int.Parse(unicodeValue.Substring(2), NumberStyles.HexNumber);

            if (unicodeValue.Length == 7) //UTF-32
            {
                return char.ConvertFromUtf32(unicode);
            }

            return ((char)unicode).ToString(); //UTF-16
        }

Cheers

Re: Converting a unicode value (with a surrogate pair) to a character in C#

Richard MacCutchan2-Jan-11 2:40

Richard MacCutchan

2-Jan-11 2:40

I just came across this article[^] which may also contain some useful information.

Just say 'NO' to evaluated arguments for diadic functions! Ash

Re: Converting a unicode value (with a surrogate pair) to a character in C#

jschell2-Jan-11 8:57

Re: Converting a unicode value (with a surrogate pair) to a character in C#

2-Jan-11 8:57

I suspect the following would also work.

int unicode = int.Parse(unicodeValue.Substring(2), NumberStyles.HexNumber);
return char.ConvertFromUtf32(unicode);

Liao Jichen24-Feb-11 13:37

Liao Jichen

24-Feb-11 13:37

You can parse the "U+XXXXX" string into a integer of unicode, which in your case should be unicode=0x0002A601. Then you can ensurrogate to have two integers hi and lo.

int unicode, hi, lo;
unicode=0x0002A601;
hi = (unicode - 0x10000) / 0x400 + 0xD800;
lo = (unicode - 0x10000) % 0x400 + 0xDC00;

string s = new String(new char[] { Convert.ToChar(hi), Convert.ToChar(lo) });

The string s is 𪘁.

BTW, dealing with unicode, you may want to use System.Globalization.StringInfo.GetTextElementEnumerator to get a TextElement, check MSDN for more details.

Exception Handling

satsumatable31-Dec-10 1:16

satsumatable

31-Dec-10 1:16

Hi,

I have C# application with WCF service though I have proper Try.. Catch block in my application very rare when my application crashes or something that sort it didn't get into Catch Block and simply pop-up .Net debug window. What is the best way to configure my application to handle all the run time exception? Is there any configuration need to be set at Web/Application configuration etc ?

Thanks

Hiren solanki31-Dec-10 1:28

Hiren solanki

31-Dec-10 1:28

satsumatable wrote:
when my application crashes or something that sort it didn't get into Catch Block and simply pop-up .Net debug window.

When you're debugging with VS environment then I think it will always notify you with pop-up block when error occurs though you've specified try..catch..

satsumatable wrote:
What is the best way to configure my application to handle all the run time exception?

It's handling Exception itself, for the need it invented.

satsumatable wrote:
Is there any configuration need to be set at Web/Application configuration etc ?

Nothing just use Try..Catch block and Log the error catched by exception handling. That's it.

Regards,
Hiren.

My Recent Article: - Way to know which control have raised a postback
My Recent Tip/Trick: - Building Hierarchy using Recursive CTE

satsumatable31-Dec-10 1:39

satsumatable

31-Dec-10 1:39

static void CurrentDomain_UnhandledException(object sender, UnhandledExceptionEventArgs e)
{
}

Will this resolve ?

Hiren solanki31-Dec-10 1:43

Hiren solanki

31-Dec-10 1:43

See THIS[^] article for more detailed information.

Regards,
Hiren.

My Recent Article: - Way to know which control have raised a postback
My Recent Tip/Trick: - Building Hierarchy using Recursive CTE

Rob Philpott31-Dec-10 3:22

Rob Philpott

31-Dec-10 3:22

Sounds like you've got first chance exception-handling switched on in Visual Studio. Visual studio normally breaks on an unhandled exception, but you can change a setting so it happens 'first chance' on all exceptions, so even though you've got an exception block (which will still work just fine if you hit F5) it will break there none-the-less.

Have a look in your Debug->Exceptions menu.

Regards,
Rob Philpott.

Pete O'Hanlon31-Dec-10 3:24

Pete O'Hanlon

31-Dec-10 3:24

satsumatable wrote:
What is the best way to configure my application to handle all the run time exception?

You can't catch all runtime exceptions. If your application causes a stack overflow, or you run out of memory, the application is terminated immediately without going to the exception handler.

I'm not a stalker, I just know things. Oh by the way, you're out of milk.

Forgive your enemies - it messes with their heads

My blog | My articles | MoXAML PowerToys | Onyx

jschell31-Dec-10 7:59

31-Dec-10 7:59

satsumatable wrote:
have C# application with WCF service though I have proper Try.. Catch block in my application very rare when my application crashes or something that sort it didn't get into Catch Block and simply pop-up .Net debug window

There are three cases that can cause that.
1. Exceptions that cannot be caught. There are three of those, out of memory, stack overflow and an odd ball one that I can't remember and probably has nothing to do with your problem.
2. Exceptions that exits a thread block excluding the specific thread specific ones like interrupt. Any such exception will cause an application exit. The way to prevent this is to insure that all threads have try/catch at the top level. This includes asynchronous methods. And that might be the cause of your problem.
3. Unmanaged code and/or net errors. The second of these would be outside your control. The first means that you are using unmanaged code so presumably you would be aware of that.

Also note that AppDomain.UnhandledException will NOT prevent an application exit. All it does is provide a place for you to log what the exception was.

What free library for printing product details? - we will need tables, colors, frames

ramit singh5-Jan-11 17:18

ramit singh

5-Jan-11 17:18

Try Windward Reports. With Windwards Microsoft Word, Excel or PowerPoint can be used as your layout. Windwards Report http://www.windwardreports.com/csharp.htm[^] is very use to use and is super fast.Various different operations can be used quite easily which are difficult with other tools.
For more details please go to : http://www.windwardreports.com/csharp.htm[^]

haiaw31-Dec-10 0:57

haiaw

31-Dec-10 0:57

Hi,
Do you know some free library for easy and nice printing of documents concerning for example product details?
I know two tools - Crystal Reports, but they are not free
Word templates - but there must be MS Office installed on the machine on which the report will be printed.

I need something similar, not necessarily editable in a template way but providing nice looking prints of customer and product details

Thanks in advance?

Re: What free library for printing product details? - we will need tables, colors, frames

OriginalGriff31-Dec-10 0:59

OriginalGriff

31-Dec-10 0:59

Have you considered PDF? Nearly everyone has a PDF reader installed these days, and they can all print.

Real men don't use instructions. They are only the manufacturers opinion on how to put the thing together.

Re: What free library for printing product details? - we will need tables, colors, frames

Henry Minute31-Dec-10 12:05

Henry Minute

31-Dec-10 12:05

Do an internet search for c# open source reporting.

You will get loads of hits, so get your reading glasses on.

Henry Minute

Do not read medical books! You could die of a misprint. - Mark Twain
Girl: (staring) "Why do you need an icy cucumber?"
“I want to report a fraud. The government is lying to us all.”

How to add .h file(Header file) in c#

sarang_k30-Dec-10 17:47

sarang_k

30-Dec-10 17:47

Hi all,

I am having one header file i.e., .h file in c++ and i want to add it to my c# windows application.

How can i do this ?

Thanks in advance.

Not Active30-Dec-10 17:50

Not Active

30-Dec-10 17:50

You can't. C# has no concept of a header file. You need to create a class or struct.

Please at least look at some documentation on the language before you try using it.

I know the language. I've read a book. - _Madmatt

Bernhard Hiller30-Dec-10 19:41

Bernhard Hiller

30-Dec-10 19:41

Add a C++ project to your projects. In the C++ project, create a class implementing the header file's methods and properties, then reference that C++ project from your C# projects. That's a few steps more complicated than we would like to have it, but it is feasible.

DaveyM6931-Dec-10 0:05

DaveyM69

31-Dec-10 0:05

As Mark says, you can't.

You will need to recreate all the functions prototypes and constants in a C# class. Any structures that are used will also need to be recreated. You will need to make use of the contents of the System.Runtime.InteropServices[^] namespace.

You may find www.pinvoke.net[^] useful as most of the Windows things have already been done there.

Dave

Binging is like googling, it just feels dirtier.
Please take your VB.NET out of our nice case sensitive forum.
Astonish us. Be exceptional. (Pete O'Hanlon)

BTW, in software, hope and pray is not a viable strategy. (Luc Pattyn)

Ravi Sant31-Dec-10 0:11

Ravi Sant

31-Dec-10 0:11

You don't and can't use a header file in C#.

One of the advantages of using C# over C++ is precisely the fact that it doesn't use header files.

You can only use C++ header files indirectly in C# by referencing a C++ library,
which allows you to access anything declared as public in the header files
that were compiled into it.