用utf8-string读写utf8文件（Windows和Linux下都行）

本文主要是介绍用utf8-string读写utf8文件（Windows和Linux下都行），希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

gtk2hs在windows下读取utf8文件，显示出来会出现乱码。

根据下面资料使用utf8-string进行utf8文本文件的读写操作，就能解决乱码问题。

注：用Windows自带的记事本新建的utf8文件开头有一个UTF8字符，即三个字节：/239/187/191。

参考：

http://hackage.haskell.org/package/utf8-string

http://www.haskell.org/haskellwiki/UTF-8

http://zincer.blogbus.com/logs/49781044.html

官方示例代码 @ http://www.haskell.org/haskellwiki/UTF-8

import System.IO.UTF8
import Prelude hiding (readFile, writeFile)
import System.Environment (getArgs)
main :: IO ()
main =
do args <- getArgs
    mapM_ reverseUTF8File args

reverseUTF8File :: FilePath -> IO ()
reverseUTF8File f =
do c <- readFile f
     writeFile (f ++ ".rev") $ reverseLines c
where
    reverseLines = unlines . map reverse . lines

本人代码：

-- file: main.hs

module Main where

import Graphics.UI.Gtk
import Graphics.UI.Gtk.Glade
import System.IO.UTF8
import Prelude hiding (readFile, writeFile, putStrLn, print)

main = do
         initGUI

-- load up the glade file
dialogXmlM <- xmlNew "gbhs.glade"
let dialogXml = case dialogXmlM of
        (Just dialogXml) -> dialogXml
        Nothing -> error "can't find the glade file /"simple.glade/" /
    /in the current directory"

-- get a handle on a couple widgets from the glade file
window <- xmlGetWidget dialogXml castToWindow "dialog1"
button1 <- xmlGetWidget dialogXml castToButton "button1"
button2 <- xmlGetWidget dialogXml castToButton "button2"
entry <- xmlGetWidget dialogXml castToEntry "entry1"

-- do something with the widgets, just to prove it works
button1 `onClicked`
                        do
                         text <- readFile "utf8.txt"
    entrySetText entry text
                         --putStrLn text
button2 `onClicked`
                        do
                         text <- entryGetText entry
                         writeFile "utf8.txt" text
                         --putStrLn text
window `onDestroy` mainQuit

-- show everything
widgetShowAll window
mainGUI

gbhs.glade文件：

<?xml version="1.0"?>
<glade-interface>


<widget class="GtkDialog" id="dialog1">
    <property name="border_width">5</property>
    <property name="title" translatable="yes">用utf8-string读写utf8文件</property>
    <property name="type_hint">normal</property>
    <property name="has_separator">False</property>
    <child internal-child="vbox">
      <widget class="GtkVBox" id="dialog-vbox1">
        <property name="visible">True</property>
        <property name="orientation">vertical</property>
        <property name="spacing">2</property>
        <child>
          <widget class="GtkEntry" id="entry1">
            <property name="visible">True</property>
            <property name="can_focus">True</property>
            <property name="invisible_char">●</property>
          </widget>
          <packing>
            <property name="position">1</property>
          </packing>
        </child>
        <child internal-child="action_area">
          <widget class="GtkHButtonBox" id="dialog-action_area1">
            <property name="visible">True</property>
            <property name="layout_style">end</property>
            <child>
              <widget class="GtkButton" id="button1">
                <property name="label" translatable="yes">读文件（Read）</property>
                <property name="visible">True</property>
                <property name="can_focus">True</property>
                <property name="receives_default">True</property>
              </widget>
              <packing>
                <property name="expand">False</property>
                <property name="fill">False</property>
                <property name="position">0</property>
              </packing>
            </child>
            <child>
              <widget class="GtkButton" id="button2">
                <property name="label" translatable="yes">写文件（Write）</property>
                <property name="visible">True</property>
                <property name="can_focus">True</property>
                <property name="receives_default">True</property>
              </widget>
              <packing>
                <property name="expand">False</property>
                <property name="fill">False</property>
                <property name="position">1</property>
              </packing>
            </child>
          </widget>
          <packing>
            <property name="expand">False</property>
            <property name="pack_type">end</property>
            <property name="position">0</property>
          </packing>
        </child>
      </widget>
    </child>
</widget>
</glade-interface>