RTF内容中包含中文，请注意是直接包含了中文。{\rtf1\ansi\deff0{\fonttbl{\f0\froman Tms Rmn;}{\f1\fswiss Arial;}}{\colortbl\red0\green0\blue0;\red0\green0\blue255;\red0\green255\blue255;\red0\green255\blue0;\red255\green0\blue255;\red255\green0\blue0;\red255\green255\blue0;\red255\green255\blue255;\red0\green0\blue127;\red0\green127\blue127;\red0\green127\blue0;\red127\green0\blue127;\red127\green0\blue0;\red127\green127\blue0;\red127\green127\blue127;\red192\green192\blue192;}{\info{\creatim\yr1996\mo9\dy6\hr10\min22\sec23}{\version1}{\vern262367}}\paperw19281\paperh43558\margl0\margr10686\margt0\margb22907\deftab720\pard\ql\li0\fi0\ri3004{\f1\fs20\cf0\up0\dn0 \loch\af1 }{\f0\fs20\cf0\up0\dn0 \loch\af0 English words}{\f0\fs20\cf5\up0\dn0 \dbch\af0 在这里}{\par}\pard\ql\li0\fi0\ri3004}因为中文是直接包含在RTF内容中的，我用了多种Encoding的方法还是显示为乱码。
由于你rtf编码用的字符集是 "froman Tms Rmn",请把这个改为 "fcharset134"就可以了.测试如下string s = @"{\rtf1\ansi\deff0{\fonttbl{\f0\fcharset134;}{\f1\fswiss Arial;}}{\colortbl\red0\green0\blue0;\red0\green0\blue255;\red0\green255\blue255;\red0\green255\blue0;\red255\green0\blue255;\red255\green0\blue0;\red255\green255\blue0;\red255\green255\blue255;\red0\green0\blue127;\red0\green127\blue127;\red0\green127\blue0;\red127\green0\blue127;\red127\green0\blue0;\red127\green127\blue0;\red127\green127\blue127;\red192\green192\blue192;}{\info{\creatim\yr1996\mo9\dy6\hr10\min22\sec23}{\version1}{\vern262367}}\paperw19281\paperh43558\margl0\margr10686\margt0\margb22907\deftab720\pard\ql\li0\fi0\ri3004{\f1\fs20\cf0\up0\dn0 \loch\af1 }{\f0\fs20\cf0\up0\dn0 \loch\af0 English words}{\f0\fs20\cf5\up0\dn0 \dbch\af0 在这里}{\par}\pard\ql\li0\fi0\ri3004}";this.richTextBox1.Rtf = s;输出
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