Package inputenc Error: Unicode char u8: not set up for use with LaTeX.

用TexStudio编辑文档时，不知是多加了空格还是啥，总是提示如下错误： 

Package inputenc Error: Unicode char u8:  not set up for use with LaTeX.

 删除掉一些内容（code）之后可以成功编译，不过添加（code）之后，又反复出现了。如此几次，真是抓狂。

遂到tex.stackchange.com上找寻到：戳这里。说是有Non-Breaking Space。

依照其添加了：

DeclareUnicodeCharacter{00A0}{~}

不过问题依旧啊。

阅读文档：

This is due to the utf8 definition not necessarily having a mapping of all the character glyphs you are able to enter on your keyboard. 

后面还提到：

With XeTeX and LuaTeX the inputenc package is no longer needed. Both engines support UTF-8 directly and allow the use of TTF and OpenType fonts to support Unicode characters. See the Fonts7 section for more information.

将编译环境换成XeLatex，不过汉字完全不见了！！

继续搜索'XeLatex 中文'，原来是缺少宏包，引入宏包（注释掉原来的CJK宏包引用，貌似会造成冲突）：

usepackage{xeCJK}

成功编译。相信这次是从根源上解决了这个问题。