Do BlazeDS not support all character of UTF-8 ?

Question

Our project use Flex 、BlazeDS 、Java.

Answer 1

I hope you mean you are using Flash CS3? because Flash 3 is from more than 10 years ago and doesn't support AS2 or unicode AFAIK.
Assuming that you are using CS3 and that your XML file is properly saved as UTF-8. Then the usual problem is that the special character has not been embedded in the text field or that the font doesn't have that character.
But first are you sure that the file is saved as UTF-8? I ask because many people have come to these forums and say that their file is UTF-8 and we work on it for a couple of days and at the end they find out that it isn't. Just adding the UTF-8 header tag to a text file does not make it UTF-8. Whatever program that created the file must support proper UTF-8 encoding.
You don't need to do any special escaping or converting the character to html code. If it is unicode just type the character normally. And save your XML file.
The next thing to check is whether Flash is reading the character correctly. You can do this in a number of ways. What I usually do is have the code that reads the XML and then either trace the nodes from the onLoad handler. Or in the test environment I go to the debug menu and "List Variables." That will show all the variables and their value. If the character shows properly in the output window then you know that the file is encoded properly and that Flash is reading it properly and that the problem must be with the textfield and the font embedding.
If the character isn't right in the output window then you know that the problem is with the text encoding.